[labnetwork] STS DRIE Multiplex Lip Seal failures (UPDATE)
Mark Weiler
mweiler at andrew.cmu.edu
Thu Jan 27 13:42:06 EST 2022
FYI... I did not perform an O2 or Ar plasma burn in on these seals.
Best Regards,
Mark
________________________________________________________________
Mark Weiler
Manager, Equipment & Facilites
Bertucci Nanotechnology Laboratory
Eden Hall Cleanroom
Carnegie Mellon University
P: 412-268-2471
F: 412-268-3497
http://www.nanofab.ece.cmu.edu
"Be kind; everyone is on their own journey." Daniel Ek
Sent from my iPhone
> On Jan 27, 2022, at 12:43 PM, Kurt Kupcho <kurt.kupcho at wisc.edu> wrote:
>
>
> With a 13s lip seal burn with O2 plasma of SPTS lip seals I can get 0.4mt/min leak up rate. With limiting O2 plasma cleans after SF6/O2 runs to the minimum amount of time to clean out the SF6 we are also able to extend the lifetime significantly.
>
> I am still interested in Mark’s new lip seals though because these lip seals will probably not be available from SPTS much longer. They already stopped supporting anything about our tool model over 5 years ago.
>
> Kurt
>
>
> Kurt Kupcho
> Materials Science Engineer
> Nanoscale Fabrication Center (NFC)
> University of Wisconsin
> 1550 Engineering Dr.
> ECB 3110
> Madison, WI 53706
> E: kurt.kupcho at wisc.edu
> T: 608-262-2982
> <image002.png>
>
> From: Aebersold,Julia W. <julia.aebersold at louisville.edu>
> Sent: Thursday, January 27, 2022 11:40 AM
> To: Mark Weiler <mweiler at andrew.cmu.edu>; Fab Network <labnetwork at mtl.mit.edu>; Kurt Kupcho <kurt.kupcho at wisc.edu>
> Cc: LaFleur, David W <dlafleur at cns.fas.harvard.edu>; Daniel Christensen <dcchrist at wisc.edu>
> Subject: RE: [labnetwork] STS DRIE Multiplex Lip Seal failures (UPDATE)
>
> We have been able to get a good life from lip deals when the substrates are clean, chamber cleans before each etch process and maintaining a helium leak up rates well below 10.
>
> Cheers!
>
> Julia Aebersold, Ph.D.
> Manager, Micro/Nano Technology Center
> University of Louisville
> Shumaker Research Building, Room 233
> 2210 South Brook Street
> Louisville, KY 40292
> (502) 852-1572
>
> http://louisville.edu/micronano/
>
> From: Mark Weiler [mailto:mweiler at andrew.cmu.edu]
> Sent: Thursday, January 27, 2022 11:05 AM
> To: Fab Network <labnetwork at mtl.mit.edu>; Kurt Kupcho <kurt.kupcho at wisc.edu>; Aebersold,Julia W. <julia.aebersold at louisville.edu>
> Cc: LaFleur, David W <dlafleur at cns.fas.harvard.edu>; Daniel Christensen <dcchrist at wisc.edu>
> Subject: Re: [labnetwork] STS DRIE Multiplex Lip Seal failures (UPDATE)
>
> CAUTION: This email originated from outside of our organization. Do not click links, open attachments, or respond unless you recognize the sender's email address and know the contents are safe.
> Hello Everyone,
>
> I have some good results to share on our quest for a better DRIE Lip Seal.
>
> The Argon conditioning of the OEM seals did result in a somewhat longer lifetime, but as it was only a single seal test point, I can’t say whether it was truly the Ar Plasma that helped.
>
> We did, however, install our new higher temp and chemical resistant Lip Seal design last summer and they are still sealing at <1mT LUR. This is great for our Bosch processing here, but will likely fail simply because I am writing an email regarding some success, and we all know Mr. Murphy hates that.
>
> Kurt and Julia, you had mentioned similar difficulties with your tools at Wisconsin and Louisville…
>
> If anyone would like ordering information… just let me know.
>
> Best Regards,
>
> Mark
>
> ________________________________________________________________
>
> Mark Weiler
> Manager, Equipment & Facilities
> Bertucci Nanotechnology Laboratory
> Eden Hall Nanofabrication Cleanroom
> Carnegie Mellon University
> P: 412-268-2471
> F: 412-268-3497
> http://www.nanofab.ece.cmu.edu
>
> <image003.png>
>
>
> On Mar 11, 2019, at 4:40 PM, Kurt Kupcho <kurt.kupcho at wisc.edu> wrote:
>
> Thanks Mark.
>
> I would be interested in hearing your Ar lipseal burn results as well.
>
> Kurt
>
>
> ---------------------------------------------------
> Kurt Kupcho
> Process Engineer/Safety Officer
>
> NFC
> 1550 Engineering Drive
> ECB Room 3110
> Madison, WI 53706
>
> E: kurt.kupcho at wisc.edu
> T: 608-262-2982
>
> <image001.png>
>
> From: Mark Weiler [mailto:mweiler at andrew.cmu.edu]
> Sent: Monday, March 11, 2019 3:33 PM
> To: Kurt Kupcho
> Cc: LaFleur, David W; Fab Network
> Subject: Re: [labnetwork] STS DRIE Multiplex Lip Seal failures
>
> Hi Kurt,
>
> I will let you know the results of the new seals… In the meantime, I am also creating an Argon lip seal conditioning recipe to see if it will be a kinder-gentler approach to seal conditioning.
>
> Mark
>
>
> ________________________________________________________________
>
> Mark Weiler
> Equipment & Facilites Manager
> Clair and John Bertucci Nanotechnology Laboratory
> Eden Hall Nanofabrication Cleanroom
> Carnegie Mellon University
> P: 412-268-2471
> http://www.nanofab.ece.cmu.edu
>
>
> <image002.png>
>
>
>
> On Mar 11, 2019, at 3:55 PM, Kurt Kupcho <kurt.kupcho at wisc.edu> wrote:
>
> Hi Mark & David –
>
> I was on vacation so I apologize for my late thoughts on this STS DRIE lipseal issue.
>
> I am the engineer in charge of the STS DRIE at UW-Madison. When I first started the lipseals were great – throw one in the system and it would last about 6 months with no issues. Then about a few years ago we noticed that wafers would stick to new lipseals and pop-off causing the transfer system to miss. To fix this new issue at the time STS told us to do a lipseal burn, or what equates to a 10s O2 plasma of the exposed lipseal. The wafers stopped sticking then, but never had to do that before and still do to this day. First, piece of evidence that something was different. Then we also saw a greatly reduced lifetime of these lipseals from 6 months to weeks. Second, piece of evidence that something was different. So, I have been fighting with SPTS for several years now that something changed with their lipseals and they refuse to admit anything. What it comes down to is these tools are obsolete to them but they are happy to sell you a $250 lipseal if you still want it. However, we do not see black residue on the back of the wafer where it contacted the lipseal. Because the lipseals are so expensive and lasting a few weeks is not sustainable we reduced our O2 plasma clean times, which seems to increase the lipseal lifetime significantly.
>
> Mark, with that said we are very interested here at the UW in your effort to make your own lipseals. Please let me know how we can help and get involved in this endeavor with you.
>
> Best,
>
> Kurt
>
>
> ---------------------------------------------------
> Kurt Kupcho
> Process Engineer/Safety Officer
>
> NFC
> 1550 Engineering Drive
> ECB Room 3110
> Madison, WI 53706
>
> E: kurt.kupcho at wisc.edu
> T: 608-262-2982
>
> <image001.png>
>
> From: labnetwork-bounces at mtl.mit.edu [mailto:labnetwork-bounces at mtl.mit.edu] On Behalf Of Mark Weiler
> Sent: Wednesday, March 06, 2019 8:04 AM
> To: LaFleur, David W
> Cc: Fab Network
> Subject: Re: [labnetwork] STS DRIE Multiplex Lip Seal failures
>
> Hi David,
>
> I am currently working with an elastomer manufacturer to produce O-Rings and seals for the systems of a material that can withstand better temperature ranges and chemical attacks. If you would like, I can share the information with you and maybe you can join us in this endeavor. The cost for the tooling and mold is now at ~1900 dollars, but I have negotiated the seal price to around 130.00 ea. I have not yet tested this material but we are having a seal made specifically for the Bosch process and 02 cleans.
>
> It is my believe that Orbotech has changed suppliers, or has allowed their supplier to switch their material source without testing, all in an effort to shave costs.
>
> My new efforts have also yielded a lower cost (50%) for the ceramic components in the chamber. I will test these and get back with the lab network sharing the source and part number.
>
> Thank you for sharing your info; now I know we are not the only ones “feeling the pain” so to speak and can officially commiserate... LOL
>
> Best,
>
> Mark
>
> Mark Weiler
> Equipment & Facilities Manager
> Claire and John Bertucci Nanotechnology Laboratory
> Electrical and Computer Engineering | Carnegie Mellon University
> 5000 Forbes Ave., Pittsburgh, PA 15213-3890
> T: 412.268.2471
> F: 412.268.3497
> www.ece.cmu.edu
> nanofab.ece.cmu.edu
>
> On Mar 6, 2019, at 08:46, LaFleur, David W <dlafleur at cns.fas.harvard.edu> wrote:
>
> Hi Mark,
>
> We have an STS MP0579 ICP which uses the lip seals. It is used mostly for silicon and SiO2 etches with O2 cleans between uses. Most of our Bosch processes are run on SPTS Rapier which uses an ESC. That has its own set of issues. We find the lip seals don’t last more than 2-3 weeks in our system. Our chamber o-rings usually go for 2 months at best. I was thinking of changing to a kalrez o-ring and always wondered if they made a Kalrez lip seal. One suggestion on how to make them last longer is make sure they don’t get exposed to any solvents like Isopropyl when you are installing them. I want to say I am not happy with the longevity of the lip seals either and maybe we need to bring this to the attention of Orbotech/SPTS. Maybe they have a solution. Other than that they are good tools, very reliable, and heavily used here at Harvard. Because they are so heavily used with so many processes we find a biweekly chamber clean and lip seal replacement works well for everyone. This is why I have just lived with the lip seals as they are.
>
> Regards,
>
> David LaFleur
> Equipment Engineer
> CNS, Harvard University
>
> From: "labnetwork-bounces at mtl.mit.edu" <labnetwork-bounces at mtl.mit.edu> on behalf of Mark Weiler <mweiler at andrew.cmu.edu>
> Date: Tuesday, March 5, 2019 at 3:44 PM
> To: Fab Network <labnetwork at mtl.mit.edu>
> Subject: [labnetwork] STS DRIE Multiplex Lip Seal failures
>
> Hello Everyone,
>
> We have gone through seven new lip seals purchased form Orbotech/SPTS. They are often failing before we even finish qualifying the system, or within a month thereafter.
>
> Our our process is stable with power and parameters not deviating over the past decade. However, I ordered the most recent batch of lip seals because the wafer seals we had been using were coming out with black residue after only a few runs… however, the current ones do the same. Not only have the lips seals disintegrated, but the chamber lid o-ring and bottom ceramic spool o-ring have also failed with black rubber material shedding off. It’s as if they are made of Buna and not meant for this application.
>
> Our process is typical Bosch with 100 sccm C4F8 and 20 sccm O2 for etching switching off with ~50 Sccm SF6 for passivation at a processing pressure of 15 mTorr, Coil power 600-800W, Platen power 100-150W, Bias voltage 50-100v (up to 200 peak-to-peak), Platen temp at 19 degrees, Lid temp 41 degrees. Qual wafers are new bare Silicon. Etch rates are normal and stable with 10+ years of data…. we just can’t complete the work due to failing seals.
>
> Our chamber base pressure is between 1E-8 and 5E-8 Torr each morning. When we put in a brand new seal and run only the LUR, it passes with 0.00 mTorr/minute leak rate. That jumps to 3.00 mTorr/m after only 30 minutes of the SPTS recommended O2 Clean… then rises as time and more runs progress. Wafers are coming out with black rings on their backsides.
>
> This should not be happening, and I believe it is due to incorrect material of the lip seals and o-rings. I am pinging the network, though, to see if there might be a parameter change we need to effect that may assist us.
>
> Have any of you seen this before?
>
> Best regards,
>
> Mark
>
>
> ________________________________________________________________
>
> Mark Weiler
> Equipment & Facilites Manager
> Clair and John Bertucci Nanotechnology Laboratory
> Eden Hall Nanofabrication Cleanroom
> Carnegie Mellon University
> P: 412-268-2471
> http://www.nanofab.ece.cmu.edu
>
>
> <image001.png>
>
>
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