Keyboard Shortcuts
Likes
- VacuumX
- Messages
Search
|
Re: plasma cleaning system making soot
Aurigema, Andrew N. (KSC-ASRC-491)[ASRC AEROSPACE]
开云体育No I don’t clean it between runs.? It is pretty big and cleaning it is a day long adventure.? I do keep it clean though so there is not any random oils just on the surfaces.? The soot is pretty uniform so it must be made from lots of surfaces all over the place.? ? Is soot generation a problem for anybody else ??? ? ? From:
VacuumX@... [mailto:VacuumX@...] On Behalf Of Anderson,
Gordon (Hovensa) ? ? Andrew, Obviously it's?contamination reacting with the plasma.? Do you clean your whole chamber with acetone every run?? Try not to use silicon grease as it will capture contaminants and also migrate everywhere and collect more.? It's also very difficult to remove.??Finger prints are also a source.? Using non powdered latex gloves can help.?? ? ? Gordon Anderson Senior I&E Specialist Project Services ? ? ? Hovensa Disclaimer: This message and any attachment to it is
intended only for the use of the individual or entity to whom it is addressed;
it contains information that is proprietary and confidential, and may be
privileged and exempt from disclosure under applicable law. If the reader of
this message is not the intended recipient or the employee or agent responsible
for delivering the message to the intended recipient, you are hereby notified
that any dissemination, distribution or copying of this communication is
strictly prohibited. IF YOU HAVE RECEIVED THIS COMMUNICATION IN ERROR, PLEASE:
(A) DO NOT READ THIS E-MAIL MESSAGE, FORWARD IT TO ANY PERSON, SAVE IT, PRINT
IT, OR OTHERWISE USE IT; (B) DELETE IT FROM YOUR COMPUTER SYSTEM; AND (C)
NOTIFY THE SENDER, BY RETURN E-MAIL, OF THE MISTAKEN TRANSMISSION.
|
|
Re: plasma cleaning system making soot
Sounds like you may be getting backstreaming from your mechanical pump. What is your crossover pressure? You should never have the mechanical pump open to the chamber below about 80 mTorr. Don Hey gang, ? I just cant seem to run my plasma cleaning system without it making soot on the optical surfaces.? I am using the very expensive DOW 714 oil in both of my diffusion pumps, have water coolant on the oil traps above the pumps and only have 15kv on the transformer.? Yet the plasma makes soot every time I turn it on.? If I leave it off ??.. no soot. ? Any ideas on how to eliminate the soot but still be able to use the plasma cleaning system ??? ? Drew in sunny Florida ? ? ? -- ____________________________________
Donald M. Mattox Society of Vacuum Coaters 71 Pinon Hill Place NE Albuquerque, NM? 87122-1914 Telephone 505/856-7188 FAX 505/856-6716 E-mail donmattox@... WebSite? http://www.svc.org |
|
Re: plasma cleaning system making soot
Anderson, Gordon (Hovensa)
开云体育Andrew,
Obviously it's?contamination reacting with the plasma.?
Do you clean your whole chamber with acetone every run?? Try not to use silicon grease as it will capture contaminants and also migrate everywhere and collect more.? It's also very difficult to remove.??Finger
prints are also a source.? Using non powdered latex gloves can help.??
?
?
Gordon Anderson
Senior I&E Specialist
Project Services
? ?
Hovensa Disclaimer: This message and any attachment to it is intended only for the use of the individual or entity to whom it is addressed; it contains information that is proprietary and confidential, and may be privileged and exempt from disclosure under applicable law. If the reader of this message is not the intended recipient or the employee or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. IF YOU HAVE RECEIVED THIS COMMUNICATION IN ERROR, PLEASE: (A) DO NOT READ THIS E-MAIL MESSAGE, FORWARD IT TO ANY PERSON, SAVE IT, PRINT IT, OR OTHERWISE USE IT; (B) DELETE IT FROM YOUR COMPUTER SYSTEM; AND (C) NOTIFY THE SENDER, BY RETURN E-MAIL, OF THE MISTAKEN TRANSMISSION. . |
|
Re: plasma cleaning system making soot
Aurigema, Andrew N. (KSC-ASRC-491)[ASRC AEROSPACE]
开云体育Oops……… that was 704 Dow silicone oil in the pumps ? From:
VacuumX@... [mailto:VacuumX@...] On Behalf Of Aurigema,
Andrew N. (KSC-ASRC-491)[ASRC AEROSPACE] ? ? Hey gang, ? I just cant seem to run my plasma cleaning system without it making soot on the optical surfaces.? I am using the very expensive DOW 714 oil in both of my diffusion pumps, have water coolant on the oil traps above the pumps and only have 15kv on the transformer.? Yet the plasma makes soot every time I turn it on.? If I leave it off …….. no soot. ? Any ideas on how to eliminate the soot but still be able to use the plasma cleaning system ??? ? Drew in sunny Florida ? ? ?
|
|
plasma cleaning system making soot
Aurigema, Andrew N. (KSC-ASRC-491)[ASRC AEROSPACE]
开云体育Hey gang,
?
I just cant seem to run my plasma cleaning system without it making soot on the optical surfaces.? I am using the very expensive DOW 714 oil in both of my diffusion pumps, have water coolant on the oil traps above the pumps and only have 15kv on the transformer.?
Yet the plasma makes soot every time I turn it on.? If I leave it off …….. no soot.
?
Any ideas on how to eliminate the soot but still be able to use the plasma cleaning system ???
?
Drew in sunny Florida
?
?
?
|
|
Re: Diffusion Pump Design & Construction
Bill,
toggle quoted message
Show quoted text
To echo what others are likely to have said, large diffusion pumps are often available on eBay for a song. They are less desirable than small pumps, just because there are fewer amateur applications for the big ones. I've seen many of them go for less than the value of the scrap stainless. Unless you really enjoy the concept of reinventing the wheel, you would be better off by buying a large diffusion pump ready built off eBay for $100 or so, cleaning it out and applying it to your chamber. The pump oil is likely going to cost you more than the pump itself, regardless of whether you build or buy one. For a chamber of the dimensions you propose, I'd look for a 10" or 12" throat diameter to keep your pumpdown time in the reasonable range. A turbopump would be even better, and sometimes, deals can be found if you don't mind piecing together a turbo head from one seller and a controller from another. Complete, ready to run package deals are always more expensive than individual parts. The cables are always the hardest part to find, and the connectors often tend to be proprietary. Avoid deals that are listed as "No Returns Allowed", or you may find an expensive boat anchor. Dave On 5/3/2010 1:48 PM, B. wrote:
Hello Group |
|
Re: Diffusion Pump Design & Construction
开云体育Thanks Ken Yes I look forward to some input on this one. I Have been thru the groups file section & photo and found them to be very helpful. Mr. Lerch has also ?been extremely help to, but always more questions. If I buy I want to be sure that the Eq is correct for the project due to my budget. That’s one of the reasons I was looking at Diffusion design and construction, but may end up out sourcing? for both units. The chamber is in work, so one step at a time until completion. Thank for the welcome Bill ? From:
VacuumX@... [mailto:VacuumX@...] On Behalf Of Ken ? ? Hi Bill...
|
|
Re: Diffusion Pump Design & Construction
开云体育Hello Actually this is in work…. Hmmm did not really think it was that lager (8.25 CuFt.) A turbo would be awesome but the cost is … well ???? So for now a Diffusion will have to do. Looking at a 6”, but will be adequate for reasonable pump downs( 1-2 hours)? Will check out your link and review Thanks Bill ? From:
VacuumX@... [mailto:VacuumX@...] On Behalf Of Aurigema,
Andrew N. (KSC-ASRC-491)[ASRC AEROSPACE] ? ? I would be more concerned about getting the chamber before thinking about the pumps.? A 36” diameter chamber is not a trivial thing.? Do you already have one ??? ??I searched ebay for a year before I found something that big to use and then it was a year more to re-condition it.? ?? ? I suggest a turbo pump for the high end and a really big bad mechanical for the atmospheric ?to low evacuating.? I run a Leybold ??similar to this ? but 3 phase.? My chamber is bigger than you are thinking about but your chamber will take a pump this big or many many hours of a smaller one.? ? Drew in sunny Florida ? From:
VacuumX@... [mailto:VacuumX@...] On Behalf Of B. ? ? Hello Group
|
|
Re: Diffusion Pump Design & Construction
Aurigema, Andrew N. (KSC-ASRC-491)[ASRC AEROSPACE]
开云体育I would be more concerned about getting the chamber before thinking about the pumps.? A 36” diameter chamber is not a trivial thing.? Do you already have one ??? ??I searched ebay for a year before I found something that big to use and then it was a year more to re-condition it.? ?? ? I suggest a turbo pump for the high end and a really big bad mechanical for the atmospheric ?to low evacuating.? I run a Leybold ??similar to this ? but 3 phase.? My chamber is bigger than you are thinking about but your chamber will take a pump this big or many many hours of a smaller one.? ? Drew in sunny Florida ? From:
VacuumX@... [mailto:VacuumX@...] On Behalf Of B. ? ? Hello Group
|
|
Re: Diffusion Pump Design & Construction
Ken
Hi Bill...
toggle quoted message
Show quoted text
Welcome to VacuumX. Good questions, some answers should be forthcoming from some of the members soon. In the mean time, there is a lot of information that you can check in the VacuumX Group's files, photo's and link's sections on the web page while you are waiting for answers. Ken Hunter --- In VacuumX@..., "B." <bill177@...> wrote:
|
|
Diffusion Pump Design & Construction
Hello Group
This is my first posting to the group. I am in the process of preliminary thoughts relating to a coating system. I was looking for information to look at designing and constructing a diffusion pump verses purchasing one, off coarse sizing is part of the process to. The size of the containment is or will be 36" in diameter @ 14 inches in depth, so approximately 8.25 sq.ft. internal volume minus internal components. I have at my disposal a reasonably complete machine shop so this aspect is complete. So that being said.... 1. Is there a rule of thumb for sizing the Roughing pump for reasonable pump and makeup due to degassing time? 2. Same Q relating to the diffusion pump? 3. More Q's guaranteed, relating to instrumentation etc. Thanks and look forward to your responses. Bill |
|
Re: pirani with ordinary?? bulb
Great links but on Ebay you could sometimes get a commercial/industrial vacuum gauge in great working condition for only around 35$ or even less sometimes. I have bought 4 under 1 year from Ebay and the last one only a week ago for a combined price of around 100$. It has been one with a linear output and the rest with analog outputs and some with setponts as well.
I had some years ago planned to to build one like in the links but then i found that these types existed on Ebay and they worked right away so there wasnt any reason to that anymore, and they also had the required vacuum fitting needed. Just thought you might wanted to know. Regards Henry |
|
pirani with ordinary? bulb
ChrisOe
Some years ago I built several pirani gages using 110 V Christmas lights and 110 V panel light bulbs. I preferred the Christmas lights as they were chap on sale after Christmas. If details are of interest I may (!) be able to find some info in old files. From my memory the reasoning for design and construction was as follows:
If you google you will find several home-built projects with schematics including: http://people.umass.edu/dac/projects/LightBulb_Pirani/Light_Bulb_Pirani_Gage_Project.html http://www.coultersmithing.com/OldStuff/piranigage.html http://www.vacuumlab.com/Articles/VacLab45.pdf www.physics.utah.edu/Phys5739/resources/Vacuum%20for%20SEM.ppt Hope this helps CUO |
|
pirani whit ordinary bulb
I read a post on and other group
where the guy try to make a pirani detector and control for reading whit ordinary buld the kind of bulb we found on fancy cnadelabra whit flame form he cut the end and plug a kind of tube whit epoxy and afte degaxe it in the chamber he have not yet made the controler but waht do you thing about his chance to meke it realy is it realistic is it makable how can we help him jack 47'N 71'W group |
|
Re: Useing nickle in tungsten boat
Aurigema, Andrew N. (KSC-ASRC-491)[ASRC AEROSPACE]
开云体育I agree.? That deep purple coating is only about 40% reflective but it is very tough.? I coated my secondary a little wrong about 2 years ago and it still looks perfect……. But is only 40% reflective.? So if can go less on the power and let the aluminum evaporate away the tungsten will stay behind as nasty looking crystals. ? Drew ? From:
VacuumX@... [mailto:VacuumX@...] On Behalf Of Thomas
Janstrom ? ? That’s why Kevin at Mid Western Tungsten recommended the alumina coated tungsten boats, nickel wets tungsten a little too well shall we say…. ? Funny but aluminium does this too, but the low BP means you get, in effect, fractional distillation happening leaving the W behind as the dissolved aluminium evaporates out of solution. Too much power (my best guess after much thought) and you can actually evaporate an aluminium/tungsten complex that will deposit out giving blue black coatings. Just ask Drew in Sunny (?) Florida. ? Cheers, Thomas Janstrom. Little Gems.
? |
|
Re: Useing nickle in tungsten boat
开云体育That’s why Kevin at Mid Western Tungsten recommended the alumina coated tungsten boats, nickel wets tungsten a little too well shall we say…. ? Funny but aluminium does this too, but the low BP means you get, in effect, fractional distillation happening leaving the W behind as the dissolved aluminium evaporates out of solution. Too much power (my best guess after much thought) and you can actually evaporate an aluminium/tungsten complex that will deposit out giving blue black coatings. Just ask Drew in Sunny (?) Florida. ? Cheers, Thomas Janstrom. Little Gems.
? From: VacuumX@...
[mailto:VacuumX@...] On Behalf Of sciotoa
Sent: Sunday, 4 April 2010 9:54 PM To: VacuumX@... Subject: [VacuumX] Re: Useing nickle in tungsten boat ? ? Hi Henry, That is very possible. The nickel has
a high melting point and by the time it melts in the boat everything is very
hot. Once it did melt it was only a mater of seconds before the boat melted
down and there was a little bit of a black film all over everything.
|
|
Re: Useing nickle in tungsten boat
Hi Henry, That is very possible. The nickel has a high melting point and by the time it melts in the boat everything is very hot. Once it did melt it was only a mater of seconds before the boat melted down and there was a little bit of a black film all over everything.
toggle quoted message
Show quoted text
Roger --- In VacuumX@..., "henry_3507" <kmnhij@...> wrote:
|
|
Re: Useing nickle in tungsten boat
Isnt there any risk that the tungsten would be disolved into the nickel so it would be a deposit of both? It might not matter perhaps just wanted to mention it if this now micht be the case.
toggle quoted message
Show quoted text
Regards Henry --- In VacuumX@..., "sciotoa" <sciotoa@...> wrote:
|
|
Newest toy
Attila
Hi All,
Today I accuired a new toy for me. This is a Balzers BA-500 coater. It is in bad condition, but I got a lot of spare parts with it. Two Balzers DUO-25 forvacuumpump, two diffusion pump, a lot of Apiezon AP201 diffusion oil, gages fittings, Viton orings,boats,evaporation materials. So I can play a lot with it. Possibly I am going to rebuild and install an electron beam evaporation source under the chamber. Attila The Hun |