|
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into the vacuum chamber after all the aluminizing is done so that a pure ALO3 coating can form for a few atoms thick ????? This would be after the high vac systems are all isolated and all the power is turned off ( right before I would normally open the chamber door ).? Maybe for 12 or 24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the formula is ???? I don’t like the idea of putting O2 in the chamber but if the vacuum is still pretty hard then there should not be a problem.?
Thanks
Andrew in soggy Florida
|
Anderson, Gordon \(Hovensa\)
Hi Andrew,
I asked the same question in 2006 and got?this
response from James Lerch:?
?
> I used O2 from my cutting torch once,
didn't notice any difference.? After coating the mirror, I held the tip of
the cutting torch in the opening for the vacuum relief?valve?and let a
partial pressure of O2 back in.? The chamber pressure was perhaps at 30
torr or so..?? Maybe if I'd brought the chamber upto ATM pressure, it
would have made a difference.. (shrug)
?
Also got this response from Thomas
Janstrom:
?
> From: Thomas
Janstrom
> To:
> Sent: Tuesday, November
21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and AL
>
> I
think firing up your plasma cleaning arc would make a BIG
difference, this
way the O2 would get ionised and therefore be so much
more reactive than cold
O2 is. Just a thought...
>
> As a matter of habit I always run the
plasma cycle after evaporating
the aluminum (prior to venting the chamber).
I'll have to try that
again with O2, but I'll have to back fill with O2, then
pump it back
down again to get a decent Plasma
going.
>
I still have to build a chamber to try it out.?
?
You'd need a lot of O2 for your chamber unless the ionizer
technique works at low concentration.? I considered using tubing into the
chamber to direct the O2 across the mirrors surface to make it more
effective.? How would you test?the density and uniformity of the
coating?
?
Gordon Anderson
?
?
Hey Guys,
Has anybody heard of putting a puff of pure O2 (
oxygen ) into the vacuum chamber after all the aluminizing is done so that a
pure ALO3 coating can form for a few atoms thick ????? This would be
after the high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ).? Maybe for 12 or 24
hours of O2 soak ??????
If you have, and this magic is real can you let me
know what the formula is ???? I don’t like the idea of putting O2 in the
chamber but if the vacuum is still pretty hard then there should not be a
problem.?
Thanks
Andrew in soggy Florida
|
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
I was only planning on bringing the chamber back up to 1
torr or less from hard vacuum so there will not be a lot of O2 in the
chamber.?
?
I just dont want to make a fuel / air bomb by doing
someting stupid like turning on an ignition source ( plasma cleaning system ) in
a pure O2 atmosphere.? I am not sure what partial pressure O2 becomes
dangerous at.? I would presume?1 / 760 of an atmosphere simply cant
sustain combustion?in any form but can react elementally with aluminum to
form the coating.?
?
Now I wish I had not slept thru chemestry
class.???
?
James, you out there to chime in on this
???
?
Thomas you out there to chime in on this
???????
?
Andrew in sunny Florida
Hi Andrew,
I asked the same question in 2006 and got?this
response from James Lerch:?
?
> I used O2 from my cutting torch once,
didn't notice any difference.? After coating the mirror, I held the tip of
the cutting torch in the opening for the vacuum relief?valve?and let a
partial pressure of O2 back in.? The chamber pressure was perhaps at 30
torr or so..?? Maybe if I'd brought the chamber upto ATM pressure, it
would have made a difference.. (shrug)
?
Also got this response from Thomas
Janstrom:
?
> From: Thomas
Janstrom
> To:
> Sent: Tuesday,
November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and
AL
>
> I think firing up your plasma cleaning arc would make a
BIG
difference, this way the O2 would get ionised and therefore be so
much
more reactive than cold O2 is. Just a thought...
>
> As a
matter of habit I always run the plasma cycle after evaporating
the aluminum
(prior to venting the chamber). I'll have to try that
again with O2, but I'll
have to back fill with O2, then pump it back
down again to get a decent
Plasma going.
>
I still have to build a chamber to try it out.?
?
You'd need a lot of O2 for your chamber unless the ionizer
technique works at low concentration.? I considered using tubing into the
chamber to direct the O2 across the mirrors surface to make it more
effective.? How would you test?the density and uniformity of the
coating?
?
Gordon Anderson
?
?
Hey Guys,
Has anybody heard of putting a puff of pure O2 (
oxygen ) into the vacuum chamber after all the aluminizing is done so that a
pure ALO3 coating can form for a few atoms thick ????? This would be
after the high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ).? Maybe for 12 or 24
hours of O2 soak ??????
If you have, and this magic is real can you let me
know what the formula is ???? I don’t like the idea of putting O2 in the
chamber but if the vacuum is still pretty hard then there should not be a
problem.?
Thanks
Andrew in soggy Florida
|
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Oh,? before I forget again.........? I ran my
chamber a few days ago and had the plasma cleaning system on for about?3
hours ( from 0.5 torr down to around 10-4 torr ) and created an amazing dark
purple blue black?discoloration in the chamber.? I have made lots of
discoloration but this was really dark, really purple and way more than it has
ever done.??It is only on the metal parts of the chamber ( not the
glass portholes ) so I am thinking it?has to do with the grounding path
from the plasma cleaner ( purple hase of death ).? ??
?
What is that deep purple coating I am
creating??????? It is now firmly "burned" onto my chamber
walls everywhere.??Aluminum from the emitters has covered a lot of it
but there are large sections of the chamber shielded from the evaporation cycle
and they all have a new purple coating.??It will not?rub off like
the deposited aluminum over it will.? It is really stuck on the chamber
walls.??
?
Is this some kind of nitrogen + 7500 VAC discharge plasma
byproduct ??????
?
Andrew ?
Hi Andrew,
I asked the same question in 2006 and got?this
response from James Lerch:?
?
> I used O2 from my cutting torch once,
didn't notice any difference.? After coating the mirror, I held the tip of
the cutting torch in the opening for the vacuum relief?valve?and let a
partial pressure of O2 back in.? The chamber pressure was perhaps at 30
torr or so..?? Maybe if I'd brought the chamber upto ATM pressure, it
would have made a difference.. (shrug)
?
Also got this response from Thomas
Janstrom:
?
> From: Thomas
Janstrom
> To:
> Sent: Tuesday,
November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and
AL
>
> I think firing up your plasma cleaning arc would make a
BIG
difference, this way the O2 would get ionised and therefore be so
much
more reactive than cold O2 is. Just a thought...
>
> As a
matter of habit I always run the plasma cycle after evaporating
the aluminum
(prior to venting the chamber). I'll have to try that
again with O2, but I'll
have to back fill with O2, then pump it back
down again to get a decent
Plasma going.
>
I still have to build a chamber to try it out.?
?
You'd need a lot of O2 for your chamber unless the ionizer
technique works at low concentration.? I considered using tubing into the
chamber to direct the O2 across the mirrors surface to make it more
effective.? How would you test?the density and uniformity of the
coating?
?
Gordon Anderson
?
?
Hey Guys,
Has anybody heard of putting a puff of pure O2 (
oxygen ) into the vacuum chamber after all the aluminizing is done so that a
pure ALO3 coating can form for a few atoms thick ????? This would be
after the high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ).? Maybe for 12 or 24
hours of O2 soak ??????
If you have, and this magic is real can you let me
know what the formula is ???? I don’t like the idea of putting O2 in the
chamber but if the vacuum is still pretty hard then there should not be a
problem.?
Thanks
Andrew in soggy Florida
|
Andrew,
It's my understanding that aluminum forms a self protecting oxide
nearly instantaneously upon exposure to oxygen.? Because the Al2O3 film
is so hard and sticks so well to the metallic aluminum, it protects the
pure metal from further oxidation.?
However, if you scratch the surface, then the exposed metal just
oxidizes again, practically instantly.?
My bet is that it would make no appreciable difference whether you let
pure O2 into the chamber, or just let the 21% O2 in the air hit the
bare metal surface.
BTW, you can burn Al metal in air if you know the trick.? I used to get
long curly aluminum drill cuttings, clamp the ends in heavy clip leads
from a low voltage, high current AC transformer, apply current with a
Variac till the shaving starts to sag, and then pull the shaving
apart.? The broken ends would often burn white hot like strips of
magnesium.? A neat demonstration!
Dave
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE] wrote:
toggle quoted message
Show quoted text
I was only planning on bringing
the chamber back up to 1 torr or less from hard vacuum so there will
not be a lot of O2 in the chamber.?
?
I just dont want to make a fuel
/ air bomb by doing someting stupid like turning on an ignition source
( plasma cleaning system ) in a pure O2 atmosphere.? I am not sure what
partial pressure O2 becomes dangerous at.? I would presume?1 / 760 of
an atmosphere simply cant sustain combustion?in any form but can react
elementally with aluminum to form the coating.?
?
Now I wish I had not slept thru
chemestry class.???
?
James, you out there to chime in
on this ???
?
Thomas you out there to chime in
on this ???????
?
Andrew in sunny Florida
Hi Andrew,
I asked the same question in
2006 and got?this response from James Lerch:?
?
> I used O2 from my cutting
torch once, didn't notice any difference.? After coating the mirror, I
held the tip of the cutting torch in the opening for the vacuum
relief?valve?and let a partial pressure of O2 back in.? The chamber
pressure was perhaps at 30 torr or so..?? Maybe if I'd brought the
chamber upto ATM pressure, it would have made a difference.. (shrug)
?
Also got this response from
Thomas Janstrom:
?
>
From: Thomas Janstrom
> To:
> Sent: Tuesday, November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and AL
>
> I think firing up your plasma cleaning arc would make a BIG
difference, this way the O2 would get ionised and therefore be so much
more reactive than cold O2 is. Just a thought...
>
> As a matter of habit I always run the plasma cycle after
evaporating
the aluminum (prior to venting the chamber). I'll have to try that
again with O2, but I'll have to back fill with O2, then pump it back
down again to get a decent Plasma going.
>
I still have to build a chamber
to try it out.?
?
You'd need a lot of O2 for your
chamber unless the ionizer technique works at low concentration.? I
considered using tubing into the chamber to direct the O2 across the
mirrors surface to make it more effective.? How would you test?the
density and uniformity of the coating?
?
Gordon Anderson
?
?
Hey Guys,
Has anybody heard of putting a puff of
pure O2 ( oxygen ) into the vacuum chamber after all the aluminizing is
done so that a pure ALO3 coating can form for a few atoms thick ?????
This would be after the high vac systems are all isolated and all the
power is turned off ( right before I would normally open the chamber
door ).? Maybe for 12 or 24 hours of O2 soak ??????
If you have, and this magic is real
can you let me know what the formula is ???? I don’t like the idea of
putting O2 in the chamber but if the vacuum is still pretty hard then
there should not be a problem.?
Thanks
Andrew in soggy Florida
|
my wife used a o2 compressor
?
it concentrated the o2 by filtering at 98
%
?
maybe that can help also?
just fill a balloon of O2 before open the
chamber
?
jack 47'N 71'W
?
toggle quoted message
Show quoted text
Hi Andrew,
I asked the same question in 2006 and got?this
response from James Lerch:?
?
> I used O2 from my cutting torch once,
didn't notice any difference.? After coating the mirror, I held the tip
of the cutting torch in the opening for the vacuum relief?valve?and
let a partial pressure of O2 back in.? The chamber pressure was perhaps
at 30 torr or so..?? Maybe if I'd brought the chamber upto ATM
pressure, it would have made a difference..
(shrug)
?
Also got this response from Thomas
Janstrom:
?
> From: Thomas
Janstrom
> To:
> Sent: Tuesday,
November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and
AL
>
> I think firing up your plasma cleaning arc would make a
BIG
difference, this way the O2 would get ionised and therefore be so
much
more reactive than cold O2 is. Just a thought...
>
> As a
matter of habit I always run the plasma cycle after evaporating
the
aluminum (prior to venting the chamber). I'll have to try that
again with
O2, but I'll have to back fill with O2, then pump it back
down again to get
a decent Plasma going.
>
I still have to build a chamber to try it out.?
?
You'd need a lot of O2 for your chamber unless the
ionizer technique works at low concentration.? I considered using tubing
into the chamber to direct the O2 across the mirrors surface to make it more
effective.? How would you test?the density and uniformity of the
coating?
?
Gordon Anderson
?
?
Hey Guys,
Has anybody heard of putting a puff of pure O2 (
oxygen ) into the vacuum chamber after all the aluminizing is done so that a
pure ALO3 coating can form for a few atoms thick ????? This would be
after the high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ).? Maybe for 12 or
24 hours of O2 soak ??????
If you have, and this magic is real can you let me
know what the formula is ???? I don’t like the idea of putting O2 in the
chamber but if the vacuum is still pretty hard then there should not be a
problem.?
Thanks
Andrew in soggy Florida
|
Anderson, Gordon \(Hovensa\)
The thought is to produce a pure oxide layer without all
the other impurities from earth's atmosphere mixed in such as?Water,
Sulfur, etc...? A certain professional mirror coated uses ion assisted
process with?pure O2.
?
Gordon Anderson
x3239
?
?
Andrew,
It's my understanding that aluminum forms a
self protecting oxide nearly instantaneously upon exposure to oxygen.?
Because the Al2O3 film is so hard and sticks so well to the metallic aluminum,
it protects the pure metal from further oxidation.?
However, if you
scratch the surface, then the exposed metal just oxidizes again, practically
instantly.?
My bet is that it would make no appreciable difference
whether you let pure O2 into the chamber, or just let the 21% O2 in the air hit
the bare metal surface.
BTW, you can burn Al metal in air if you know the
trick.? I used to get long curly aluminum drill cuttings, clamp the ends in
heavy clip leads from a low voltage, high current AC transformer, apply current
with a Variac till the shaving starts to sag, and then pull the shaving
apart.? The broken ends would often burn white hot like strips of
magnesium.? A neat demonstration!
Dave
Aurigema,
Andrew N. (KSC)[ASRC AEROSPACE] wrote:
toggle quoted message
Show quoted text
I was only planning on bringing the chamber back up to 1
torr or less from hard vacuum so there will not be a lot of O2 in the
chamber.?
?
I just dont want to make a fuel / air bomb by doing
someting stupid like turning on an ignition source ( plasma cleaning system )
in a pure O2 atmosphere.? I am not sure what partial pressure O2 becomes
dangerous at.? I would presume?1 / 760 of an atmosphere simply cant
sustain combustion?in any form but can react elementally with aluminum to
form the coating.?
?
Now I wish I had not slept thru chemestry
class.???
?
James, you out there to chime in on this
???
?
Thomas you out there to chime in on this
???????
?
Andrew in sunny Florida
Hi Andrew,
I asked the same question in 2006 and got?this
response from James Lerch:?
?
> I used O2 from my cutting torch once,
didn't notice any difference.? After coating the mirror, I held the tip
of the cutting torch in the opening for the vacuum relief?valve?and
let a partial pressure of O2 back in.? The chamber pressure was perhaps
at 30 torr or so..?? Maybe if I'd brought the chamber upto ATM
pressure, it would have made a difference..
(shrug)
?
Also got this response from Thomas
Janstrom:
?
> From: Thomas
Janstrom
> To:
>
Sent: Tuesday, November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and
AL
>
> I think firing up your plasma cleaning arc would make a
BIG
difference, this way the O2 would get ionised and therefore be so
much
more reactive than cold O2 is. Just a thought...
>
> As a
matter of habit I always run the plasma cycle after evaporating
the
aluminum (prior to venting the chamber). I'll have to try that
again with
O2, but I'll have to back fill with O2, then pump it back
down again to get
a decent Plasma going.
>
I still have to build a chamber to try it out.?
?
You'd need a lot of O2 for your chamber unless the
ionizer technique works at low concentration.? I considered using tubing
into the chamber to direct the O2 across the mirrors surface to make it more
effective.? How would you test?the density and uniformity of the
coating?
?
Gordon Anderson
?
?
Hey Guys,
Has anybody heard of putting a puff of pure O2 (
oxygen ) into the vacuum chamber after all the aluminizing is done so that a
pure ALO3 coating can form for a few atoms thick ????? This would be
after the high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ).? Maybe for 12 or
24 hours of O2 soak ??????
If you have, and this magic is real can you let me
know what the formula is ???? I don’t like the idea of putting O2 in the
chamber but if the vacuum is still pretty hard then there should not be a
problem.?
Thanks
Andrew in soggy Florida
|
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
I was thinking of medical O2 so I dont have to make wet O2
or anything like that.? I was going to just put in a balloon's worth.?
The question is to put on the high voltage or not ???
?
I am inclined to try it without first but dont see how 100%
O2 is that different from 20% O2 from the normal back fill air.? Maybe it
needs to have the high energy from the plasma cleaning system to make the
chemestry work.? I just dont know.
?
Andrew in sunny Florida
my wife used a o2 compressor
?
it concentrated the o2 by filtering at 98
%
?
maybe that can help also?
just fill a balloon of O2 before open the
chamber
?
jack 47'N 71'W
?
toggle quoted message
Show quoted text
Hi Andrew,
I asked the same question in 2006 and got?this
response from James Lerch:?
?
> I used O2 from my cutting torch once,
didn't notice any difference.? After coating the mirror, I held the tip
of the cutting torch in the opening for the vacuum relief?valve?and
let a partial pressure of O2 back in.? The chamber pressure was perhaps
at 30 torr or so..?? Maybe if I'd brought the chamber upto ATM
pressure, it would have made a difference..
(shrug)
?
Also got this response from Thomas
Janstrom:
?
> From: Thomas
Janstrom
> To:
> Sent: Tuesday,
November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and
AL
>
> I think firing up your plasma cleaning arc would make a
BIG
difference, this way the O2 would get ionised and therefore be so
much
more reactive than cold O2 is. Just a thought...
>
> As a
matter of habit I always run the plasma cycle after evaporating
the
aluminum (prior to venting the chamber). I'll have to try that
again with
O2, but I'll have to back fill with O2, then pump it back
down again to get
a decent Plasma going.
>
I still have to build a chamber to try it out.?
?
You'd need a lot of O2 for your chamber unless the
ionizer technique works at low concentration.? I considered using tubing
into the chamber to direct the O2 across the mirrors surface to make it more
effective.? How would you test?the density and uniformity of the
coating?
?
Gordon Anderson
?
?
Hey Guys,
Has anybody heard of putting a puff of pure O2 (
oxygen ) into the vacuum chamber after all the aluminizing is done so that a
pure ALO3 coating can form for a few atoms thick ????? This would be
after the high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ).? Maybe for 12 or
24 hours of O2 soak ??????
If you have, and this magic is real can you let me
know what the formula is ???? I don’t like the idea of putting O2 in the
chamber but if the vacuum is still pretty hard then there should not be a
problem.?
Thanks
Andrew in soggy Florida
|
Hi Andrew, I wouldn't try anything near 100% pure oxygen. You never know what might be lurking in your giant vacuum chamber. Any oil or other substance (PVC) not usually flammable can burst into flame in a pure oxygen environment. Especially when you are planning on using a plasma discharge. BOOOOOM! They use PVC as the solid fuel in hybrid rockets using nitrous oxide or pure oxygen as the oxidizer. Also interesting is that some systems use high voltage discharge to ignite the PVC/NOX mix. BOOOOM ZOOOOM!! Also is wet oxygen a myth? I have heard that medical and welding oxygen is no different. How could you have water vapor in a tank of oxygen under high pressure and expect the metal of the tank to not rapidly corrode? I have seen devices that bubble the oxygen through water before patients breath it. Why would that be needed if it was wet oxygen? Roy M. --- In VacuumX@..., "Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]" <andrew.n.aurigema@...> wrote:
I was thinking of medical O2 so I dont have to make wet O2 or
anything like that. I was going to just put in a balloon's worth. The question is to put on the high voltage or not ???
I am inclined to try it without first but dont see how 100% O2 is that different from 20% O2 from the normal back fill air. Maybe it needs to have the high energy from the plasma cleaning system to make the
chemestry work. I just dont know.
Andrew in sunny Florida
________________________________
From: VacuumX@... [mailto:VacuumX@...] On Behalf Of jacques savard
Sent: Saturday, September 13, 2008 11:18 AM
To: VacuumX@...
Subject: Re: [VacuumX] O2 for thin film formation
my wife used a o2 compressor
it concentrated the o2 by filtering at 98 %
maybe that can help also
just fill a balloon of O2 before open the chamber
jack 47'N 71'W
Hi Andrew,
I asked the same question in 2006 and got this response from
James Lerch:
> I used O2 from my cutting torch once, didn't notice any
difference. After coating the mirror, I held the tip of the cutting
torch in the opening for the vacuum relief valve and let a partial
pressure of O2 back in. The chamber pressure was perhaps at 30 torr or so.. Maybe if I'd brought the chamber upto ATM pressure, it would have made a difference.. (shrug)
Also got this response from Thomas Janstrom:
> From: Thomas Janstrom
> To: VacuumX@...
< postID=2HCNBbnSaglQd2yAJQUJU zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
> Sent: Tuesday, November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and AL
>
> I think firing up your plasma cleaning arc would make a BIG
difference, this way the O2 would get ionised and therefore be
so much
more reactive than cold O2 is. Just a thought...
>
> As a matter of habit I always run the plasma cycle after
evaporating
the aluminum (prior to venting the chamber). I'll have to try
that
again with O2, but I'll have to back fill with O2, then pump it back
down again to get a decent Plasma going.
>
I still have to build a chamber to try it out.
You'd need a lot of O2 for your chamber unless the ionizer
technique works at low concentration. I considered using tubing into the chamber to direct the O2 across the mirrors surface to make it more effective. How would you test the density and uniformity of the
coating?
Gordon Anderson
Senior I&E Specialist
________________________________
From: VacuumX@... [mailto:VacuumX@...]
On Behalf Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Sent: Thursday, September 11, 2008 4:14 PM
To: VacuumX@...
Cc: SiTechservo@...
Subject: [VacuumX] O2 for thin film formation
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into
the vacuum chamber after all the aluminizing is done so that a pure ALO3 coating can form for a few atoms thick ??? This would be after the
high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ). Maybe for 12 or 24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the formula is ??? I don't like the idea of putting O2 in the chamber but if the vacuum is still pretty hard then there should not be a problem.
Thanks
Andrew in soggy Florida
|
PS I was thinking if your wife doesn't like the idea of a fusor she really won't like the oxygen bomb you are thinking about. Roy M. --- In VacuumX@..., "radroy92" <rminnich@...> wrote:
Hi Andrew,
I wouldn't try anything near 100% pure oxygen. You never know
what might be lurking in your giant vacuum chamber. Any oil or other
substance (PVC) not usually flammable can burst into flame in a pure oxygen environment. Especially when you are planning on using a
plasma discharge. BOOOOOM! They use PVC as the solid fuel in
hybrid rockets using nitrous oxide or pure oxygen as the oxidizer.
Also interesting is that some systems use high voltage discharge to
ignite the PVC/NOX mix. BOOOOM ZOOOOM!!
Also is wet oxygen a myth? I have heard that medical and welding
oxygen is no different. How could you have water vapor in a tank of oxygen under high pressure and expect the metal of the tank to not
rapidly corrode? I have seen devices that bubble the oxygen through water before patients breath it. Why would that be needed if it was wet oxygen?
Roy M.
--- In VacuumX@..., "Aurigema, Andrew N. (KSC)[ASRC
AEROSPACE]" <andrew.n.aurigema@> wrote:
I was thinking of medical O2 so I dont have to make wet O2 or
anything
like that. I was going to just put in a balloon's worth. The question
is to put on the high voltage or not ???
I am inclined to try it without first but dont see how 100% O2 is that
different from 20% O2 from the normal back fill air. Maybe it needs to
have the high energy from the plasma cleaning system to make the
chemestry work. I just dont know.
Andrew in sunny Florida
________________________________
From: VacuumX@... [mailto:VacuumX@...] On Behalf
Of jacques savard
Sent: Saturday, September 13, 2008 11:18 AM
To: VacuumX@...
Subject: Re: [VacuumX] O2 for thin film formation
my wife used a o2 compressor
it concentrated the o2 by filtering at 98 %
maybe that can help also
just fill a balloon of O2 before open the chamber
jack 47'N 71'W
Hi Andrew,
I asked the same question in 2006 and got this response from
James Lerch:
> I used O2 from my cutting torch once, didn't notice any
difference. After coating the mirror, I held the tip of the cutting torch in the opening for the vacuum relief valve and let a partial
pressure of O2 back in. The chamber pressure was perhaps at 30 torr or
so.. Maybe if I'd brought the chamber upto ATM pressure, it
would have
made a difference.. (shrug)
Also got this response from Thomas Janstrom:
> From: Thomas Janstrom
> To: VacuumX@...
< postID=2HCNBbnSaglQd2yAJQUJU
zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
> Sent: Tuesday, November 21, 2006 9:39 PM
> Subject: RE: [VacuumX] O2 and AL
>
> I think firing up your plasma cleaning arc would make a BIG
difference, this way the O2 would get ionised and therefore be
so much
more reactive than cold O2 is. Just a thought...
>
> As a matter of habit I always run the plasma cycle after
evaporating
the aluminum (prior to venting the chamber). I'll have to try
that
again with O2, but I'll have to back fill with O2, then pump it
back
down again to get a decent Plasma going.
>
I still have to build a chamber to try it out.
You'd need a lot of O2 for your chamber unless the ionizer
technique works at low concentration. I considered using tubing into
the chamber to direct the O2 across the mirrors surface to make it more
effective. How would you test the density and uniformity of the
coating?
Gordon Anderson
Senior I&E Specialist
________________________________
From: VacuumX@... [mailto:VacuumX@...]
On Behalf Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Sent: Thursday, September 11, 2008 4:14 PM
To: VacuumX@...
Cc: SiTechservo@...
Subject: [VacuumX] O2 for thin film formation
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into
the vacuum chamber after all the aluminizing is done so that a pure ALO3
coating can form for a few atoms thick ??? This would be after the high vac systems are all isolated and all the power is turned off
( right before I would normally open the chamber door ). Maybe for 12 or
24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the
formula is ??? I don't like the idea of putting O2 in the
chamber but
if the vacuum is still pretty hard then there should not be a problem.
Thanks
Andrew in soggy Florida
|
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
I was thinking of splitting water to make the O2 and that
would have water vapor with it so it would be wet.? Medical O2 is
dry.? Not sure if the welding stuff is really that
pure.
?
From what I have discovered, at 1 mm of pressure ( absolute
) nothing will burn.? 100% O2?just sounds bad because at 760 mm ( 1
atm ) it would be a very very very?bad
enviorment.?
?
Still wish somebody that actually knows about ion
deposition would chime in.? ??
Hi Andrew,
I wouldn't try anything near 100% pure oxygen. You never
know what
might be lurking in your giant vacuum chamber. Any oil or other
substance (PVC) not usually flammable can burst into flame in a pure
oxygen environment. Especially when you are planning on using a
plasma
discharge. BOOOOOM! They use PVC as the solid fuel in
hybrid rockets using
nitrous oxide or pure oxygen as the oxidizer.
Also interesting is that some
systems use high voltage discharge to
ignite the PVC/NOX mix. BOOOOM
ZOOOOM!!
Also is wet oxygen a myth? I have heard that medical and welding
oxygen is no different. How could you have water vapor in a tank of
oxygen under high pressure and expect the metal of the tank to not
rapidly corrode? I have seen devices that bubble the oxygen through
water before patients breath it. Why would that be needed if it was
wet
oxygen?
Roy M.
toggle quoted message
Show quoted text
--- In VacuumX@yahoogroups.com,
"Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]"
...> wrote: > > I was thinking of
medical O2 so I dont have to make wet O2 or anything > like that. I
was going to just put in a balloon's worth. The question > is to put
on the high voltage or not ??? > > I am inclined to try it without
first but dont see how 100% O2 is that > different from 20% O2 from
the normal back fill air. Maybe it needs to > have the high energy
from the plasma cleaning system to make the > chemestry work. I just dont
know. > > Andrew in sunny Florida > >
____________ _________ _________ __ > > From: VacuumX@yahoogroups.com
[mailto: VacuumX@yahoogroups.com] On
Behalf > Of jacques savard > Sent: Saturday, September 13, 2008
11:18 AM > To: VacuumX@yahoogroups.com>
Subject: Re: [VacuumX] O2 for thin film formation > > >
> my wife used a o2 compressor > > it concentrated the o2 by
filtering at 98 % > > maybe that can help also > just fill a
balloon of O2 before open the chamber > > jack 47'N 71'W >
> > > Hi Andrew, > I asked the same question in 2006
and got this response from > James Lerch: > > > >
I used O2 from my cutting torch once, didn't notice any > difference.
After coating the mirror, I held the tip of the cutting > torch in the
opening for the vacuum relief valve and let a partial > pressure of O2
back in. The chamber pressure was perhaps at 30 torr or > so.. Maybe
if I'd brought the chamber upto ATM pressure, it would have > made a
difference.. (shrug) > > > Also got this response from
Thomas Janstrom: > > > From: Thomas Janstrom > > To: VacuumX@yahoogroups.com>
< postID=2HCNBbnSaglQ d2yAJQUJU >
zg3fNZf5v0BlEc99ivD W__RkqgxQVqCDaSj 1ZUv2xh96Y0ROhTZ u_QYKdiIdWA>
> > Sent: Tuesday, November 21, 2006 9:39 PM > > Subject: RE:
[VacuumX] O2 and AL > > > > I think firing up your plasma
cleaning arc would make a BIG > difference, this way the O2 would get
ionised and therefore be > so much > more reactive than cold O2 is.
Just a thought... > > > > As a matter of habit I always run
the plasma cycle after > evaporating > the aluminum (prior to
venting the chamber). I'll have to try > that > again with O2, but
I'll have to back fill with O2, then pump it > back > down again
to get a decent Plasma going. > > > > I still have to
build a chamber to try it out. > > You'd need a lot of O2 for your
chamber unless the ionizer > technique works at low concentration. I
considered using tubing into > the chamber to direct the O2 across the
mirrors surface to make it more > effective. How would you test the
density and uniformity of the > coating? > > Gordon Anderson
> Senior I&E Specialist > > > > >
____________ _________ _________ __ > > From: VacuumX@yahoogroups.com
[mailto: VacuumX@yahoogroups.com] >
On Behalf Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE] > Sent: Thursday,
September 11, 2008 4:14 PM > To: VacuumX@yahoogroups.com>
Cc: SiTechservo@yahoogroups.com>
Subject: [VacuumX] O2 for thin film formation > > > >
Hey Guys, > > Has anybody heard of putting a puff of pure O2 (
oxygen ) into > the vacuum chamber after all the aluminizing is done so
that a pure ALO3 > coating can form for a few atoms thick ??? This
would be after the > high vac systems are all isolated and all the power
is turned off ( > right before I would normally open the chamber door ).
Maybe for 12 or > 24 hours of O2 soak ?????? > > If you
have, and this magic is real can you let me know what the > formula is
??? I don't like the idea of putting O2 in the chamber but > if the
vacuum is still pretty hard then there should not be a problem. >
> Thanks > > Andrew in soggy
Florida >
|
Hi Andrew, I did a Google search and I kept coming back to sputtering as the cause of the colorful coatings that develope from use of the plasma discharge cleaning system. What metal is used in your high voltage feedthroughs? And the electrodes? Roy M. --- In VacuumX@..., "Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]" <andrew.n.aurigema@...> wrote:
Oh, before I forget again......... I ran my chamber a few days
ago and had the plasma cleaning system on for about 3 hours ( from 0.5 torr down to around 10-4 torr ) and created an amazing dark purple blue black
discoloration in the chamber. I have made lots of discoloration but
this was really dark, really purple and way more than it has ever done. It is only on the metal parts of the chamber ( not the glass portholes ) so I am thinking it has to do with the grounding path from the plasma cleaner ( purple hase of death ).
What is that deep purple coating I am creating ??? It is now firmly "burned" onto my chamber walls everywhere. Aluminum from the emitters has covered a lot of it but there are large sections of the chamber
shielded from the evaporation cycle and they all have a new purple
coating. It will not rub off like the deposited aluminum over it will. It is really stuck on the chamber walls.
Is this some kind of nitrogen + 7500 VAC discharge plasma byproduct
??????
Andrew
________________________________
From: VacuumX@... [mailto:VacuumX@...] On Behalf Of Anderson, Gordon (Hovensa)
Sent: Friday, September 12, 2008 9:19 AM
To: VacuumX@...
Subject: RE: [VacuumX] O2 for thin film formation
Hi Andrew,
I asked the same question in 2006 and got this response from James
Lerch:
I used O2 from my cutting torch once, didn't notice any difference. After coating the mirror, I held the tip of the cutting torch in the
opening for the vacuum relief valve and let a partial pressure of O2
back in. The chamber pressure was perhaps at 30 torr or so.. Maybe if I'd brought the chamber upto ATM pressure, it would have made a
difference.. (shrug)
Also got this response from Thomas Janstrom:
From: Thomas Janstrom
To: VacuumX@... < postID=2HCNBbnSaglQd2yAJQUJU zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
Sent: Tuesday, November 21, 2006 9:39 PM
Subject: RE: [VacuumX] O2 and AL
I think firing up your plasma cleaning arc would make a BIG difference, this way the O2 would get ionised and therefore be so much more reactive than cold O2 is. Just a thought...
As a matter of habit I always run the plasma cycle after
evaporating the aluminum (prior to venting the chamber). I'll have to try that
again with O2, but I'll have to back fill with O2, then pump it back
down again to get a decent Plasma going.
I still have to build a chamber to try it out.
You'd need a lot of O2 for your chamber unless the ionizer technique
works at low concentration. I considered using tubing into the chamber to direct the O2 across the mirrors surface to make it more effective. How would you test the density and uniformity of the coating?
Gordon Anderson
Senior I&E Specialist
________________________________
From: VacuumX@... [mailto:VacuumX@...] On Behalf Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Sent: Thursday, September 11, 2008 4:14 PM
To: VacuumX@...
Cc: SiTechservo@...
Subject: [VacuumX] O2 for thin film formation
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into the
vacuum chamber after all the aluminizing is done so that a pure ALO3
coating can form for a few atoms thick ??? This would be after the
high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ). Maybe for 12 or 24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the formula is ??? I don't like the idea of putting O2 in the chamber but if the vacuum is still pretty hard then there should not be a problem.
Thanks
Andrew in soggy Florida
|
Anderson, Gordon \(Hovensa\)
Andrew,
Try this link:? ?
They use O2 along with Ion assist.? They give a pretty good description of
the process.? There is a link to an animation of the process on the right
side of the page as well.?
?
Water molecules would split into Oxygen and
Hydrogen.? So you'd need to separate them some how and then dry the
oxygen.? If H2O molecules are present you may have issues with the
coating.
?
?
?
toggle quoted message
Show quoted text
I was thinking of splitting water to make the O2 and that
would have water vapor with it so it would be wet.? Medical O2 is
dry.? Not sure if the welding stuff is really that
pure.
?
From what I have discovered, at 1 mm of pressure ( absolute
) nothing will burn.? 100% O2?just sounds bad because at 760 mm ( 1
atm ) it would be a very very very?bad
enviorment.?
?
Still wish somebody that actually knows about ion
deposition would chime in.? ??
Hi Andrew,
I wouldn't try anything near 100% pure oxygen. You never
know what
might be lurking in your giant vacuum chamber. Any oil or other
substance (PVC) not usually flammable can burst into flame in a pure
oxygen environment. Especially when you are planning on using a
plasma
discharge. BOOOOOM! They use PVC as the solid fuel in
hybrid rockets using
nitrous oxide or pure oxygen as the oxidizer.
Also interesting is that some
systems use high voltage discharge to
ignite the PVC/NOX mix. BOOOOM
ZOOOOM!!
Also is wet oxygen a myth? I have heard that medical and welding
oxygen is no different. How could you have water vapor in a tank of
oxygen under high pressure and expect the metal of the tank to not
rapidly corrode? I have seen devices that bubble the oxygen through
water before patients breath it. Why would that be needed if it was
wet
oxygen?
Roy M.
--- In VacuumX@yahoogroups.com,
"Aurigema, Andrew N. (KSC)[ASRC
AEROSPACE]"
...> wrote:
>
> I was thinking of
medical O2 so I dont have to make wet O2 or
anything
> like that. I
was going to just put in a balloon's worth. The
question
> is to put
on the high voltage or not ???
>
> I am inclined to try it without
first but dont see how 100% O2 is
that
> different from 20% O2 from
the normal back fill air. Maybe it
needs to
> have the high energy
from the plasma cleaning system to make the
> chemestry work. I just dont
know.
>
> Andrew in sunny Florida
>
>
________________________________
>
> From: VacuumX@yahoogroups.com
[mailto:VacuumX@yahoogroups.com] On
Behalf
> Of jacques savard
> Sent: Saturday, September 13, 2008
11:18 AM
> To: VacuumX@yahoogroups.com
>
Subject: Re: [VacuumX] O2 for thin film formation
>
>
>
> my wife used a o2 compressor
>
> it concentrated the o2 by
filtering at 98 %
>
> maybe that can help also
> just fill a
balloon of O2 before open the chamber
>
> jack 47'N 71'W
>
>
>
> Hi Andrew,
> I asked the same question in 2006
and got this response from
> James Lerch:
>
>
> >
I used O2 from my cutting torch once, didn't notice any
> difference.
After coating the mirror, I held the tip of the cutting
> torch in the
opening for the vacuum relief valve and let a partial
> pressure of O2
back in. The chamber pressure was perhaps at 30
torr or
> so.. Maybe
if I'd brought the chamber upto ATM pressure, it would
have
> made a
difference.. (shrug)
>
>
> Also got this response from
Thomas Janstrom:
>
> > From: Thomas Janstrom
> > To: VacuumX@yahoogroups.com
>
<
postID=2HCNBbnSaglQd2yAJQUJU
>
zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
> > Sent: Tuesday, November 21, 2006 9:39 PM
> > Subject: RE:
[VacuumX] O2 and AL
> >
> > I think firing up your plasma
cleaning arc would make a BIG
> difference, this way the O2 would get
ionised and therefore be
> so much
> more reactive than cold O2 is.
Just a thought...
> >
> > As a matter of habit I always run
the plasma cycle after
> evaporating
> the aluminum (prior to
venting the chamber). I'll have to try
> that
> again with O2, but
I'll have to back fill with O2, then pump
it
> back
> down again
to get a decent Plasma going.
> >
>
> I still have to
build a chamber to try it out.
>
> You'd need a lot of O2 for your
chamber unless the ionizer
> technique works at low concentration. I
considered using tubing
into
> the chamber to direct the O2 across the
mirrors surface to make it
more
> effective. How would you test the
density and uniformity of the
> coating?
>
> Gordon Anderson
> Senior I&E Specialist
>
>
>
>
>
________________________________
>
> From: VacuumX@yahoogroups.com
[mailto:VacuumX@yahoogroups.com]
>
On Behalf Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
> Sent: Thursday,
September 11, 2008 4:14 PM
> To: VacuumX@yahoogroups.com
>
Cc: SiTechservo@yahoogroups.com
>
Subject: [VacuumX] O2 for thin film formation
>
>
>
>
Hey Guys,
>
> Has anybody heard of putting a puff of pure O2 (
oxygen ) into
> the vacuum chamber after all the aluminizing is done so
that a pure
ALO3
> coating can form for a few atoms thick ??? This
would be after the
> high vac systems are all isolated and all the power
is turned off (
> right before I would normally open the chamber door ).
Maybe for
12 or
> 24 hours of O2 soak ??????
>
> If you
have, and this magic is real can you let me know what
the
> formula is
??? I don't like the idea of putting O2 in the chamber
but
> if the
vacuum is still pretty hard then there should not be a
problem.
>
> Thanks
>
> Andrew in soggy
Florida
>
|
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Roy,
?
I had not thought that the electrodes would be
disolving.? The actual passthru is a carbon steel bolt with cad
plating.? There is a cad plated nut at the end.? The "electrodes"
are?nickel cromimum stainless steel ( .040" diameter )?safety
wire.?
?
Is it possible that they are disolving slowly and
depositing on the walls of the chamber ????
?
Maybe I should switch to aluminum
electrodes????
?
Andrew
Hi Andrew,
I did a Google search and I kept coming back to sputtering
as the
cause of the colorful coatings that develope from use of the plasma
discharge cleaning system. What metal is used in your high voltage
feedthroughs? And the electrodes?
Roy M.
toggle quoted message
Show quoted text
--- In VacuumX@yahoogroups.com,
"Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]"
...> wrote: > > Oh, before I forget
again....... .. I ran my chamber a few days ago and > had the
plasma cleaning system on for about 3 hours ( from 0.5 torr down > to
around 10-4 torr ) and created an amazing dark purple blue black >
discoloration in the chamber. I have made lots of discoloration but > this
was really dark, really purple and way more than it has ever done. >
It is only on the metal parts of the chamber ( not the glass portholes
) > so I am thinking it has to do with the grounding path from the
plasma > cleaner ( purple hase of death ). > > What is
that deep purple coating I am creating ??? It is now firmly > "burned"
onto my chamber walls everywhere. Aluminum from the emitters > has
covered a lot of it but there are large sections of the chamber > shielded
from the evaporation cycle and they all have a new purple > coating. It
will not rub off like the deposited aluminum over it will. > It is
really stuck on the chamber walls. > > Is this some kind of
nitrogen + 7500 VAC discharge plasma byproduct > ?????? > >
Andrew > > ____________ _________ _________ __ >
> From: VacuumX@yahoogroups.com
[mailto: VacuumX@yahoogroups.com] On
Behalf > Of Anderson, Gordon (Hovensa) > Sent: Friday, September
12, 2008 9:19 AM > To: VacuumX@yahoogroups.com>
Subject: RE: [VacuumX] O2 for thin film formation > > >
> Hi Andrew, > I asked the same question in 2006 and got this
response from James > Lerch: > > > > I used O2
from my cutting torch once, didn't notice any difference. > After
coating the mirror, I held the tip of the cutting torch in the > opening
for the vacuum relief valve and let a partial pressure of O2 > back in.
The chamber pressure was perhaps at 30 torr or so.. Maybe if > I'd
brought the chamber upto ATM pressure, it would have made a > difference..
(shrug) > > > Also got this response from Thomas
Janstrom: > > > From: Thomas Janstrom > > To: VacuumX@yahoogroups.com>
< postID=2HCNBbnSaglQ d2yAJQUJU >
zg3fNZf5v0BlEc99ivD W__RkqgxQVqCDaSj 1ZUv2xh96Y0ROhTZ u_QYKdiIdWA>
> > Sent: Tuesday, November 21, 2006 9:39 PM > > Subject: RE:
[VacuumX] O2 and AL > > > > I think firing up your plasma
cleaning arc would make a BIG > difference, this way the O2 would get
ionised and therefore be so much > more reactive than cold O2 is. Just
a thought... > > > > As a matter of habit I always run the
plasma cycle after evaporating > the aluminum (prior to venting the
chamber). I'll have to try that > again with O2, but I'll have to back
fill with O2, then pump it back > down again to get a decent Plasma
going. > > > > I still have to build a chamber to try it
out. > > You'd need a lot of O2 for your chamber unless the
ionizer technique > works at low concentration. I considered using tubing
into the chamber > to direct the O2 across the mirrors surface to make
it more effective. > How would you test the density and uniformity of
the coating? > > Gordon Anderson > Senior I&E
Specialist > > > > >
____________ _________ _________ __ > > From: VacuumX@yahoogroups.com
[mailto: VacuumX@yahoogroups.com] On
Behalf > Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE] > Sent:
Thursday, September 11, 2008 4:14 PM > To: VacuumX@yahoogroups.com>
Cc: SiTechservo@yahoogroups.com>
Subject: [VacuumX] O2 for thin film formation > > > >
Hey Guys, > > Has anybody heard of putting a puff of pure O2 (
oxygen ) into the > vacuum chamber after all the aluminizing is done so
that a pure ALO3 > coating can form for a few atoms thick ??? This would
be after the > high vac systems are all isolated and all the power is
turned off ( > right before I would normally open the chamber door ).
Maybe for 12 or > 24 hours of O2 soak ?????? > > If you
have, and this magic is real can you let me know what the formula > is
??? I don't like the idea of putting O2 in the chamber but if the >
vacuum is still pretty hard then there should not be a problem. >
> Thanks > > Andrew in soggy
Florida >
|
Hi Andrew,
Sorry to come in on this so late, but I've been busy with non-vacuum things.
:-(
I would swap them out for 1/8" aluminium wire post haste! The heavier the
metal the harder the radiation it puts out when used for ion bombardment.
Just be thankful that you're not using tungsten! (Out put is in the soft
X-rays with 15KV potential applied or so I'm told.)
BTW on the pure O2 ion bombardment thing, if you put ~22L of gas at one atm
into a chamber your size the O2 partial pressure is going to be way too low
to sustain combustion, regardless of the energy your ion system puts into
the gas. But you don't need the ions to make the O2 work, Al is so reactive
that it would happen regardless anyway, this just speeds things up some.
This may also result in a more contiguous layer of AlO2 and thus better
protection of the metal coating (supposition on my part from not so recent
reading).
Cheers, Thomas Janstrom.
Little Gems.
www.tjlittlegems.com
toggle quoted message
Show quoted text
-----Original Message----- From: VacuumX@... [mailto:VacuumX@...] On Behalf Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE] Sent: Tuesday, 16 September 2008 9:19 PM To: VacuumX@... Subject: RE: [VacuumX] Re: O2 for thin film formation Roy, I had not thought that the electrodes would be disolving. The actual passthru is a carbon steel bolt with cad plating. There is a cad plated nut at the end. The "electrodes" are nickel cromimum stainless steel ( .040" diameter ) safety wire. Is it possible that they are disolving slowly and depositing on the walls of the chamber ???? Maybe I should switch to aluminum electrodes???? Andrew _____ From: VacuumX@... [mailto:VacuumX@...] On Behalf Of radroy92 Sent: Monday, September 15, 2008 4:17 PM To: VacuumX@... Subject: [VacuumX] Re: O2 for thin film formation Hi Andrew, I did a Google search and I kept coming back to sputtering as the cause of the colorful coatings that develope from use of the plasma discharge cleaning system. What metal is used in your high voltage feedthroughs? And the electrodes? Roy M. --- In VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com, "Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]" <andrew.n.aurigema@...> wrote:
Oh, before I forget again......... I ran my chamber a few days
ago and had the plasma cleaning system on for about 3 hours ( from 0.5 torr down to around 10-4 torr ) and created an amazing dark purple blue black
discoloration in the chamber. I have made lots of discoloration but
this was really dark, really purple and way more than it has ever done. It is only on the metal parts of the chamber ( not the glass portholes ) so I am thinking it has to do with the grounding path from the plasma cleaner ( purple hase of death ).
What is that deep purple coating I am creating ??? It is now firmly "burned" onto my chamber walls everywhere. Aluminum from the emitters has covered a lot of it but there are large sections of the chamber
shielded from the evaporation cycle and they all have a new purple
coating. It will not rub off like the deposited aluminum over it will. It is really stuck on the chamber walls.
Is this some kind of nitrogen + 7500 VAC discharge plasma byproduct
??????
Andrew
________________________________
From: VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com [mailto:VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com] On Behalf Of Anderson, Gordon (Hovensa)
Sent: Friday, September 12, 2008 9:19 AM
To: VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com
Subject: RE: [VacuumX] O2 for thin film formation
Hi Andrew,
I asked the same question in 2006 and got this response from James
Lerch:
I used O2 from my cutting torch once, didn't notice any difference. After coating the mirror, I held the tip of the cutting torch in the
opening for the vacuum relief valve and let a partial pressure of O2
back in. The chamber pressure was perhaps at 30 torr or so.. Maybe if I'd brought the chamber upto ATM pressure, it would have made a
difference.. (shrug)
Also got this response from Thomas Janstrom:
From: Thomas Janstrom
To: VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com <. <> yahoo.com/group/VacuumX/post? postID=2HCNBbnSaglQd2yAJQUJU zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
Sent: Tuesday, November 21, 2006 9:39 PM
Subject: RE: [VacuumX] O2 and AL
I think firing up your plasma cleaning arc would make a BIG difference, this way the O2 would get ionised and therefore be so much more reactive than cold O2 is. Just a thought...
As a matter of habit I always run the plasma cycle after
evaporating the aluminum (prior to venting the chamber). I'll have to try that
again with O2, but I'll have to back fill with O2, then pump it back
down again to get a decent Plasma going.
I still have to build a chamber to try it out.
You'd need a lot of O2 for your chamber unless the ionizer technique
works at low concentration. I considered using tubing into the chamber to direct the O2 across the mirrors surface to make it more effective. How would you test the density and uniformity of the coating?
Gordon Anderson
Senior I&E Specialist
________________________________
From: VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com [mailto:VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com] On Behalf Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Sent: Thursday, September 11, 2008 4:14 PM
To: VacuumX@yahoogroups <mailto:VacuumX%40yahoogroups.com> .com
Cc: SiTechservo@ <mailto:SiTechservo%40yahoogroups.com> yahoogroups.com
Subject: [VacuumX] O2 for thin film formation
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into the
vacuum chamber after all the aluminizing is done so that a pure ALO3
coating can form for a few atoms thick ??? This would be after the
high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ). Maybe for 12 or 24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the formula is ??? I don't like the idea of putting O2 in the chamber but if the vacuum is still pretty hard then there should not be a problem.
Thanks
Andrew in soggy Florida
|
Andrew,
I think that cadmium is not a good metal to have in a vacuum especially when heated/bombarded due to its outgassing.
John
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE] wrote:
toggle quoted message
Show quoted text
Roy,
I had not thought that the electrodes would be disolving. The actual passthru is a carbon steel bolt with cad plating. There is a cad plated nut at the end. The "electrodes" are nickel cromimum stainless steel ( .040" diameter ) safety wire. Is it possible that they are disolving slowly and depositing on the walls of the chamber ????
Maybe I should switch to aluminum electrodes????
Andrew
------------------------------------------------------------------------
*From:* VacuumX@... [mailto:VacuumX@...] *On Behalf Of *radroy92
*Sent:* Monday, September 15, 2008 4:17 PM
*To:* VacuumX@...
*Subject:* [VacuumX] Re: O2 for thin film formation
Hi Andrew,
I did a Google search and I kept coming back to sputtering as the
cause of the colorful coatings that develope from use of the plasma
discharge cleaning system. What metal is used in your high voltage
feedthroughs? And the electrodes?
Roy M.
--- In VacuumX@... <mailto:VacuumX%40yahoogroups.com>, "Aurigema, Andrew N. (KSC)[ASRC
AEROSPACE]" <andrew.n.aurigema@...> wrote:
Oh, before I forget again......... I ran my chamber a few days
ago and
had the plasma cleaning system on for about 3 hours ( from 0.5 torr down
to around 10-4 torr ) and created an amazing dark purple blue black
discoloration in the chamber. I have made lots of discoloration but
this was really dark, really purple and way more than it has ever done.
It is only on the metal parts of the chamber ( not the glass portholes )
so I am thinking it has to do with the grounding path from the plasma
cleaner ( purple hase of death ).
What is that deep purple coating I am creating ??? It is now firmly
"burned" onto my chamber walls everywhere. Aluminum from the emitters
has covered a lot of it but there are large sections of the chamber
shielded from the evaporation cycle and they all have a new purple
coating. It will not rub off like the deposited aluminum over it will.
It is really stuck on the chamber walls.
Is this some kind of nitrogen + 7500 VAC discharge plasma byproduct
??????
Andrew
________________________________
From: VacuumX@... <mailto:VacuumX%40yahoogroups.com> [mailto:VacuumX@... <mailto:VacuumX%40yahoogroups.com>] On
Behalf
Of Anderson, Gordon (Hovensa)
Sent: Friday, September 12, 2008 9:19 AM
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
Subject: RE: [VacuumX] O2 for thin film formation
Hi Andrew,
I asked the same question in 2006 and got this response from James
Lerch:
I used O2 from my cutting torch once, didn't notice any difference.
After coating the mirror, I held the tip of the cutting torch in the
opening for the vacuum relief valve and let a partial pressure of O2
back in. The chamber pressure was perhaps at 30 torr or so.. Maybe if
I'd brought the chamber upto ATM pressure, it would have made a
difference.. (shrug)
Also got this response from Thomas Janstrom:
From: Thomas Janstrom
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com> < <>
postID=2HCNBbnSaglQd2yAJQUJU
zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
Sent: Tuesday, November 21, 2006 9:39 PM
Subject: RE: [VacuumX] O2 and AL
I think firing up your plasma cleaning arc would make a BIG difference, this way the O2 would get ionised and therefore be so much
more reactive than cold O2 is. Just a thought...
As a matter of habit I always run the plasma cycle after
evaporating
the aluminum (prior to venting the chamber). I'll have to try that
again with O2, but I'll have to back fill with O2, then pump it back
down again to get a decent Plasma going.
I still have to build a chamber to try it out.
You'd need a lot of O2 for your chamber unless the ionizer technique
works at low concentration. I considered using tubing into the chamber
to direct the O2 across the mirrors surface to make it more effective.
How would you test the density and uniformity of the coating?
Gordon Anderson
Senior I&E Specialist
________________________________
From: VacuumX@... <mailto:VacuumX%40yahoogroups.com> [mailto:VacuumX@... <mailto:VacuumX%40yahoogroups.com>] On
Behalf
Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Sent: Thursday, September 11, 2008 4:14 PM
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
Cc: SiTechservo@... <mailto:SiTechservo%40yahoogroups.com>
Subject: [VacuumX] O2 for thin film formation
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into the
vacuum chamber after all the aluminizing is done so that a pure ALO3
coating can form for a few atoms thick ??? This would be after the
high vac systems are all isolated and all the power is turned off (
right before I would normally open the chamber door ). Maybe for 12 or
24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the formula
is ??? I don't like the idea of putting O2 in the chamber but if the
vacuum is still pretty hard then there should not be a problem.
Thanks
Andrew in soggy Florida
|
Anderson, Gordon \(Hovensa\)
Hi Thomas,
Would ion impingement smooth the micro surface of the
aluminum oxide similar to electro polishing?
?
Thanks.
?
Gordon
?
?
Hi
Andrew,
?
Sorry to come in on
this so late, but I’ve been busy with non-vacuum things. L
?
I would swap them out
for 1/8” aluminium wire post haste! The heavier the metal the harder the
radiation it puts out when used for ion bombardment. Just be thankful that
you’re not using tungsten! (Out put is in the soft X-rays with 15KV potential
applied or so I’m told.)
?
BTW on the pure O2 ion
bombardment thing, if you put ~22L of gas at one atm into a chamber your size
the O2 partial pressure is going to be way too low to sustain combustion,
regardless of the energy your ion system puts into the gas. But you don’t need
the ions to make the O2 work, Al is so reactive that it would happen regardless
anyway, this just speeds things up some. This may also result in a more
contiguous layer of AlO2 and thus better protection of the metal coating
(supposition on my part from not so recent reading).
?
Cheers, Thomas
Janstrom.
Little
Gems.
www.tjlittlegems.com
?
-----Original
Message-----
From:
VacuumX@yahoogroups.com [mailto:VacuumX@yahoogroups.com] On Behalf Of Aurigema, Andrew N. (KSC)[ASRC
AEROSPACE]
Sent: Tuesday, 16
September 2008 9:19 PM
To:
VacuumX@yahoogroups.com
Subject: RE: [VacuumX] Re: O2 for thin film
formation
?
Roy,
?
I had not thought that
the electrodes would be disolving.? The actual passthru is a carbon steel
bolt with cad plating.? There is a cad plated nut at the end.? The
"electrodes" are?nickel cromimum stainless steel ( .040" diameter
)?safety wire.?
?
Is it possible that
they are disolving slowly and depositing on the walls of the chamber
????
?
Maybe I should switch
to aluminum electrodes????
?
Andrew
?
From: VacuumX@yahoogroups.com
[mailto:VacuumX@yahoogroups.com] On
Behalf Of radroy92
Sent: Monday, September 15, 2008 4:17
PM
To:
VacuumX@yahoogroups.com
Subject: [VacuumX] Re: O2 for thin film
formation
Hi
Andrew,
I did a Google search and I kept coming back to sputtering as the
cause of the colorful coatings that develope from use of the plasma
discharge cleaning system. What metal is used in your high voltage
feedthroughs? And the electrodes?
Roy M.
toggle quoted message
Show quoted text
--- In VacuumX@yahoogroups.com,
"Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]"
...> wrote: > > Oh, before I forget
again....... .. I ran my chamber a few days ago and > had the
plasma cleaning system on for about 3 hours ( from 0.5 torr down > to
around 10-4 torr ) and created an amazing dark purple blue black >
discoloration in the chamber. I have made lots of discoloration but > this
was really dark, really purple and way more than it has ever done. >
It is only on the metal parts of the chamber ( not the glass portholes
) > so I am thinking it has to do with the grounding path from the
plasma > cleaner ( purple hase of death ). > > What is
that deep purple coating I am creating ??? It is now firmly > "burned"
onto my chamber walls everywhere. Aluminum from the emitters > has
covered a lot of it but there are large sections of the chamber > shielded
from the evaporation cycle and they all have a new purple > coating. It
will not rub off like the deposited aluminum over it will. > It is
really stuck on the chamber walls. > > Is this some kind of
nitrogen + 7500 VAC discharge plasma byproduct > ?????? > >
Andrew > > ____________ _________ _________ __ >
> From: VacuumX@yahoogroups.com
[mailto: VacuumX@yahoogroups.com] On
Behalf > Of Anderson, Gordon (Hovensa) > Sent: Friday, September
12, 2008 9:19 AM > To: VacuumX@yahoogroups.com>
Subject: RE: [VacuumX] O2 for thin film formation > > >
> Hi Andrew, > I asked the same question in 2006 and got this
response from James > Lerch: > > > > I used O2
from my cutting torch once, didn't notice any difference. > After
coating the mirror, I held the tip of the cutting torch in the > opening
for the vacuum relief valve and let a partial pressure of O2 > back in.
The chamber pressure was perhaps at 30 torr or so.. Maybe if > I'd
brought the chamber upto ATM pressure, it would have made a > difference..
(shrug) > > > Also got this response from Thomas
Janstrom: > > > From: Thomas Janstrom > > To: VacuumX@yahoogroups.com>
< postID=2HCNBbnSaglQ d2yAJQUJU >
zg3fNZf5v0BlEc99ivD W__RkqgxQVqCDaSj 1ZUv2xh96Y0ROhTZ u_QYKdiIdWA>
> > Sent: Tuesday, November 21, 2006 9:39 PM > > Subject: RE:
[VacuumX] O2 and AL > > > > I think firing up your plasma
cleaning arc would make a BIG > difference, this way the O2 would get
ionised and therefore be so much > more reactive than cold O2 is. Just
a thought... > > > > As a matter of habit I always run the
plasma cycle after evaporating > the aluminum (prior to venting the
chamber). I'll have to try that > again with O2, but I'll have to back
fill with O2, then pump it back > down again to get a decent Plasma
going. > > > > I still have to build a chamber to try it
out. > > You'd need a lot of O2 for your chamber unless the
ionizer technique > works at low concentration. I considered using tubing
into the chamber > to direct the O2 across the mirrors surface to make
it more effective. > How would you test the density and uniformity of
the coating? > > Gordon Anderson > Senior I&E
Specialist > > > > >
____________ _________ _________ __ > > From: VacuumX@yahoogroups.com
[mailto: VacuumX@yahoogroups.com] On
Behalf > Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE] > Sent:
Thursday, September 11, 2008 4:14 PM > To: VacuumX@yahoogroups.com>
Cc: SiTechservo@yahoogroups.com>
Subject: [VacuumX] O2 for thin film formation > > > >
Hey Guys, > > Has anybody heard of putting a puff of pure O2 (
oxygen ) into the > vacuum chamber after all the aluminizing is done so
that a pure ALO3 > coating can form for a few atoms thick ??? This would
be after the > high vac systems are all isolated and all the power is
turned off ( > right before I would normally open the chamber door ).
Maybe for 12 or > 24 hours of O2 soak ?????? > > If you
have, and this magic is real can you let me know what the formula > is
??? I don't like the idea of putting O2 in the chamber but if the >
vacuum is still pretty hard then there should not be a problem. >
> Thanks > > Andrew in soggy
Florida >
|
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
I am beginning to think I chose poorly in my initital metal
selection for high vacuum and high voltage.?
?
I can fix that.? It is only a 1/4" x 20 tpi
bolt.? The new high voltage wiskers will be aluminum.
?
?
Andrew,
I think that cadmium is not a good metal to have in a vacuum
especially
when heated/bombarded due to its outgassing.
John
Aurigema, Andrew N. (KSC)[ASRC AEROSPACE] wrote:
>
Roy,
>
> I had not thought that the electrodes would be disolving.
The actual
> passthru is a carbon steel bolt with cad plating. There is a
cad
> plated nut at the end. The "electrodes" are nickel cromimum
stainless
> steel ( .040" diameter ) safety wire.
>
> Is it
possible that they are disolving slowly and depositing on the
> walls of
the chamber ????
>
> Maybe I should switch to aluminum
electrodes????
>
> Andrew
>
>
----------------------------------------------------------
>
*From:* VacuumX@yahoogroups.com
[mailto:VacuumX@yahoogroups.com] *On
> Behalf Of *radroy92
> *Sent:* Monday, September 15, 2008 4:17
PM
> *To:* VacuumX@yahoogroups.com
>
*Subject:* [VacuumX] Re: O2 for thin film formation
>
> Hi
Andrew,
>
> I did a Google search and I kept coming back to
sputtering as the
> cause of the colorful coatings that develope from use
of the plasma
> discharge cleaning system. What metal is used in your high
voltage
> feedthroughs? And the electrodes?
>
> Roy
M.
>
> --- In VacuumX@yahoogroups.com
40yahoogroups.com>,
> "Aurigema, Andrew
N. (KSC)[ASRC
> AEROSPACE]" ...>
wrote:
> >
> > Oh, before I forget again......... I ran
my chamber a few days
> ago and
> > had the plasma cleaning
system on for about 3 hours ( from 0.5 torr
> down
> > to around
10-4 torr ) and created an amazing dark purple blue black
> >
discoloration in the chamber. I have made lots of discoloration but
> >
this was really dark, really purple and way more than it has ever
>
done.
> > It is only on the metal parts of the chamber ( not the
glass
> portholes )
> > so I am thinking it has to do with the
grounding path from the
> plasma
> > cleaner ( purple hase of
death ).
> >
> > What is that deep purple coating I am
creating ??? It is now
> firmly
> > "burned" onto my chamber
walls everywhere. Aluminum from the
> emitters
> > has covered a
lot of it but there are large sections of the chamber
> > shielded from
the evaporation cycle and they all have a new purple
> > coating. It
will not rub off like the deposited aluminum over it
> will.
> >
It is really stuck on the chamber walls.
> >
> > Is this some
kind of nitrogen + 7500 VAC discharge plasma byproduct
> >
??????
> >
> > Andrew
> >
> >
________________________________
> >
> > From:
VacuumX@yahoogroups.com
40yahoogroups.com>
> [mailto:VacuumX@yahoogroups.com
40yahoogroups.com>] On
> Behalf
>
> Of Anderson, Gordon (Hovensa)
> > Sent: Friday, September 12, 2008
9:19 AM
> > To: VacuumX@yahoogroups.com
40yahoogroups.com>
> > Subject: RE:
[VacuumX] O2 for thin film formation
> >
> >
>
>
> > Hi Andrew,
> > I asked the same question in 2006 and
got this response from James
> > Lerch:
> >
>
>
> > > I used O2 from my cutting torch once, didn't notice
any
> difference.
> > After coating the mirror, I held the tip of
the cutting torch in the
> > opening for the vacuum relief valve and
let a partial pressure of O2
> > back in. The chamber pressure was
perhaps at 30 torr or so..
> Maybe if
> > I'd brought the chamber
upto ATM pressure, it would have made a
> > difference..
(shrug)
> >
> >
> > Also got this response from
Thomas Janstrom:
> >
> > > From: Thomas Janstrom
>
> > To: VacuumX@yahoogroups.com
40yahoogroups.com>
> > <
> <>
>
postID=2HCNBbnSaglQd2yAJQUJU
> >
zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
>
> > Sent: Tuesday, November 21, 2006 9:39 PM
> > > Subject:
RE: [VacuumX] O2 and AL
> > >
> > > I think firing up
your plasma cleaning arc would make a BIG
> > difference, this way the
O2 would get ionised and therefore be so
> much
> > more reactive
than cold O2 is. Just a thought...
> > >
> > > As a
matter of habit I always run the plasma cycle after
> evaporating
>
> the aluminum (prior to venting the chamber). I'll have to try that
>
> again with O2, but I'll have to back fill with O2, then pump it
back
> > down again to get a decent Plasma going.
> >
>
> >
> > I still have to build a chamber to try it
out.
> >
> > You'd need a lot of O2 for your chamber unless
the ionizer technique
> > works at low concentration. I considered
using tubing into the
> chamber
> > to direct the O2 across the
mirrors surface to make it more
> effective.
> > How would you
test the density and uniformity of the coating?
> >
> > Gordon
Anderson
> > Senior I&E Specialist
> >
>
>
> >
> >
> >
________________________________
> >
> > From:
VacuumX@yahoogroups.com
40yahoogroups.com>
> [mailto:VacuumX@yahoogroups.com
40yahoogroups.com>] On
> Behalf
>
> Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
> > Sent: Thursday,
September 11, 2008 4:14 PM
> > To: VacuumX@yahoogroups.com
40yahoogroups.com>
> > Cc: SiTechservo@yahoogroups.com
%40yahoogroups.com>
> > Subject:
[VacuumX] O2 for thin film formation
> >
> >
>
>
> > Hey Guys,
> >
> > Has anybody heard of
putting a puff of pure O2 ( oxygen ) into the
> > vacuum chamber after
all the aluminizing is done so that a pure ALO3
> > coating can form
for a few atoms thick ??? This would be after the
> > high vac systems
are all isolated and all the power is turned off (
> > right before I
would normally open the chamber door ). Maybe for
> 12 or
> > 24
hours of O2 soak ??????
> >
> > If you have, and this magic is
real can you let me know what the
> formula
> > is ??? I don't
like the idea of putting O2 in the chamber but if
> the
> >
vacuum is still pretty hard then there should not be a problem.
>
>
> > Thanks
> >
> > Andrew in soggy
Florida
> >
>
>
|
Hi Andrew, I think you had at least one other reply about heavy metal high voltage electrodes. Yes switch to aluminum. Very low sputtering and no problems with X-rays. I also agree cadmium is not good in a vacuum especially if it gets hot. You sure the nut is cadmium plated? More likely it's zinc. Roy M. --- In VacuumX@..., "Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]" <andrew.n.aurigema@...> wrote:
Roy,
I had not thought that the electrodes would be disolving. The
actual passthru is a carbon steel bolt with cad plating. There is a cad plated nut at the end. The "electrodes" are nickel cromimum stainless steel ( .040" diameter ) safety wire.
Is it possible that they are disolving slowly and depositing on the
walls of the chamber ????
Maybe I should switch to aluminum electrodes????
Andrew
________________________________
From: VacuumX@... [mailto:VacuumX@...] On Behalf Of radroy92
Sent: Monday, September 15, 2008 4:17 PM
To: VacuumX@...
Subject: [VacuumX] Re: O2 for thin film formation
Hi Andrew,
I did a Google search and I kept coming back to sputtering as the
cause of the colorful coatings that develope from use of the plasma
discharge cleaning system. What metal is used in your high voltage
feedthroughs? And the electrodes?
Roy M.
--- In VacuumX@... <mailto:VacuumX%40yahoogroups.com> ,
"Aurigema, Andrew N. (KSC)[ASRC
AEROSPACE]" <andrew.n.aurigema@> wrote:
Oh, before I forget again......... I ran my chamber a few days
ago and
had the plasma cleaning system on for about 3 hours ( from 0.5 torr down
to around 10-4 torr ) and created an amazing dark purple blue black discoloration in the chamber. I have made lots of discoloration
but this was really dark, really purple and way more than it has ever done.
It is only on the metal parts of the chamber ( not the glass portholes )
so I am thinking it has to do with the grounding path from the plasma
cleaner ( purple hase of death ).
What is that deep purple coating I am creating ??? It is now firmly
"burned" onto my chamber walls everywhere. Aluminum from the emitters
has covered a lot of it but there are large sections of the
chamber shielded from the evaporation cycle and they all have a new purple
coating. It will not rub off like the deposited aluminum over it will.
It is really stuck on the chamber walls.
Is this some kind of nitrogen + 7500 VAC discharge plasma
byproduct ??????
Andrew
________________________________
From: VacuumX@... <mailto:VacuumX%40yahoogroups.com> [mailto:VacuumX@... <mailto:VacuumX%
40yahoogroups.com> ] On Behalf
Of Anderson, Gordon (Hovensa)
Sent: Friday, September 12, 2008 9:19 AM
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
Subject: RE: [VacuumX] O2 for thin film formation
Hi Andrew,
I asked the same question in 2006 and got this response from James
Lerch:
I used O2 from my cutting torch once, didn't notice any difference.
After coating the mirror, I held the tip of the cutting torch in the opening for the vacuum relief valve and let a partial pressure of
O2 back in. The chamber pressure was perhaps at 30 torr or so.. Maybe if
I'd brought the chamber upto ATM pressure, it would have made a
difference.. (shrug)
Also got this response from Thomas Janstrom:
From: Thomas Janstrom
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com> < <>
postID=2HCNBbnSaglQd2yAJQUJU
zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
Sent: Tuesday, November 21, 2006 9:39 PM
Subject: RE: [VacuumX] O2 and AL
I think firing up your plasma cleaning arc would make a BIG difference, this way the O2 would get ionised and therefore be so much
more reactive than cold O2 is. Just a thought...
As a matter of habit I always run the plasma cycle after
evaporating
the aluminum (prior to venting the chamber). I'll have to try that
again with O2, but I'll have to back fill with O2, then pump it
back down again to get a decent Plasma going.
I still have to build a chamber to try it out.
You'd need a lot of O2 for your chamber unless the ionizer
technique works at low concentration. I considered using tubing into the chamber
to direct the O2 across the mirrors surface to make it more effective.
How would you test the density and uniformity of the coating?
Gordon Anderson
Senior I&E Specialist
________________________________
From: VacuumX@... <mailto:VacuumX%40yahoogroups.com> [mailto:VacuumX@... <mailto:VacuumX%
40yahoogroups.com> ] On Behalf
Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Sent: Thursday, September 11, 2008 4:14 PM
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
Cc: SiTechservo@... <mailto:SiTechservo% 40yahoogroups.com>
Subject: [VacuumX] O2 for thin film formation
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into the
vacuum chamber after all the aluminizing is done so that a pure
ALO3 coating can form for a few atoms thick ??? This would be after the
high vac systems are all isolated and all the power is turned off
( right before I would normally open the chamber door ). Maybe for 12 or
24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the formula
is ??? I don't like the idea of putting O2 in the chamber but if the
vacuum is still pretty hard then there should not be a problem.
Thanks
Andrew in soggy Florida
|
Andrew/Roy,
I think that zinc is as bad as cadmium
John
radroy92 wrote:
toggle quoted message
Show quoted text
Hi Andrew,
I think you had at least one other reply about heavy metal high
voltage electrodes. Yes switch to aluminum. Very low sputtering and
no problems with X-rays. I also agree cadmium is not good in a
vacuum especially if it gets hot. You sure the nut is cadmium
plated? More likely it's zinc.
Roy M.
--- In VacuumX@... <mailto:VacuumX%40yahoogroups.com>, "Aurigema, Andrew N. (KSC)[ASRC
AEROSPACE]" <andrew.n.aurigema@...> wrote:
Roy,
I had not thought that the electrodes would be disolving. The
actual
passthru is a carbon steel bolt with cad plating. There is a cad plated
nut at the end. The "electrodes" are nickel cromimum stainless steel (
.040" diameter ) safety wire.
Is it possible that they are disolving slowly and depositing on the
walls of the chamber ????
Maybe I should switch to aluminum electrodes????
Andrew
________________________________
From: VacuumX@... <mailto:VacuumX%40yahoogroups.com> [mailto:VacuumX@... <mailto:VacuumX%40yahoogroups.com>] On
Behalf
Of radroy92
Sent: Monday, September 15, 2008 4:17 PM
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
Subject: [VacuumX] Re: O2 for thin film formation
Hi Andrew,
I did a Google search and I kept coming back to sputtering as the
cause of the colorful coatings that develope from use of the plasma
discharge cleaning system. What metal is used in your high voltage
feedthroughs? And the electrodes?
Roy M.
--- In VacuumX@... <mailto:VacuumX%40yahoogroups.com> <mailto:VacuumX%40yahoogroups.com> ,
"Aurigema, Andrew N. (KSC)[ASRC
AEROSPACE]" <andrew.n.aurigema@> wrote:
Oh, before I forget again......... I ran my chamber a few days
ago and
had the plasma cleaning system on for about 3 hours ( from 0.5 torr
down
to around 10-4 torr ) and created an amazing dark purple blue black
discoloration in the chamber. I have made lots of discoloration
but
this was really dark, really purple and way more than it has ever done.
It is only on the metal parts of the chamber ( not the glass portholes )
so I am thinking it has to do with the grounding path from the plasma
cleaner ( purple hase of death ).
What is that deep purple coating I am creating ??? It is now firmly
"burned" onto my chamber walls everywhere. Aluminum from the emitters
has covered a lot of it but there are large sections of the
chamber
shielded from the evaporation cycle and they all have a new purple
coating. It will not rub off like the deposited aluminum over it will.
It is really stuck on the chamber walls.
Is this some kind of nitrogen + 7500 VAC discharge plasma
byproduct
??????
Andrew
________________________________
From: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
<mailto:VacuumX%40yahoogroups.com>
[mailto:VacuumX@... <mailto:VacuumX%40yahoogroups.com> <mailto:VacuumX%
40yahoogroups.com> ] On
Behalf
Of Anderson, Gordon (Hovensa)
Sent: Friday, September 12, 2008 9:19 AM
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com> <mailto:VacuumX%40yahoogroups.com>
Subject: RE: [VacuumX] O2 for thin film formation
Hi Andrew,
I asked the same question in 2006 and got this response from James
Lerch:
I used O2 from my cutting torch once, didn't notice any difference.
After coating the mirror, I held the tip of the cutting torch in
the
opening for the vacuum relief valve and let a partial pressure of
O2
back in. The chamber pressure was perhaps at 30 torr or so.. Maybe if
I'd brought the chamber upto ATM pressure, it would have made a
difference.. (shrug)
Also got this response from Thomas Janstrom:
From: Thomas Janstrom
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
<mailto:VacuumX%40yahoogroups.com>
<
<>
< <>>
postID=2HCNBbnSaglQd2yAJQUJU
zg3fNZf5v0BlEc99ivDW__RkqgxQVqCDaSj1ZUv2xh96Y0ROhTZu_QYKdiIdWA>
Sent: Tuesday, November 21, 2006 9:39 PM
Subject: RE: [VacuumX] O2 and AL
I think firing up your plasma cleaning arc would make a BIG difference, this way the O2 would get ionised and therefore be so much
more reactive than cold O2 is. Just a thought...
As a matter of habit I always run the plasma cycle after
evaporating
the aluminum (prior to venting the chamber). I'll have to try that
again with O2, but I'll have to back fill with O2, then pump it back
down again to get a decent Plasma going.
I still have to build a chamber to try it out.
You'd need a lot of O2 for your chamber unless the ionizer
technique
works at low concentration. I considered using tubing into the chamber
to direct the O2 across the mirrors surface to make it more effective.
How would you test the density and uniformity of the coating?
Gordon Anderson
Senior I&E Specialist
________________________________
From: VacuumX@... <mailto:VacuumX%40yahoogroups.com>
<mailto:VacuumX%40yahoogroups.com>
[mailto:VacuumX@... <mailto:VacuumX%40yahoogroups.com> <mailto:VacuumX%
40yahoogroups.com> ] On
Behalf
Of Aurigema, Andrew N. (KSC)[ASRC AEROSPACE]
Sent: Thursday, September 11, 2008 4:14 PM
To: VacuumX@... <mailto:VacuumX%40yahoogroups.com> <mailto:VacuumX%40yahoogroups.com>
Cc: SiTechservo@...
<mailto:SiTechservo%40yahoogroups.com> <mailto:SiTechservo%
40yahoogroups.com>
Subject: [VacuumX] O2 for thin film formation
Hey Guys,
Has anybody heard of putting a puff of pure O2 ( oxygen ) into the
vacuum chamber after all the aluminizing is done so that a pure
ALO3
coating can form for a few atoms thick ??? This would be after the
high vac systems are all isolated and all the power is turned off
(
right before I would normally open the chamber door ). Maybe for 12 or
24 hours of O2 soak ??????
If you have, and this magic is real can you let me know what the formula
is ??? I don't like the idea of putting O2 in the chamber but if the
vacuum is still pretty hard then there should not be a problem.
Thanks
Andrew in soggy Florida
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