From ericp at snf.stanford.edu Fri May 1 00:33:34 2009 From: ericp at snf.stanford.edu (ericp at snf.stanford.edu) Date: Fri, 1 May 2009 00:33:34 -0700 Subject: Comment stsetch SNF 2009-05-01 00:33:34: computer problem solved, now He problem Message-ID: I got the system to respond and run process. Now, the plasma won't strike. It appears to be a backside He interlock problem (?) as there is an alarm on the Helium controller, He pressure is 12, backside flow is ZERO, and plasma will not strike. I checked the He solenoid before the He MFC, and it's not getting pneumatic pressure to open. I'm not certain of the state of the He interlock, but it used to be the case that such a backside He problem would definitely stop plasma from striking. From eenriquez at snf.stanford.edu Fri May 1 09:53:32 2009 From: eenriquez at snf.stanford.edu (eenriquez at snf.stanford.edu) Date: Fri, 1 May 2009 09:53:32 -0700 Subject: Problem stsetch SNF 2009-04-30 17:43:38: Won't perform pump down step Message-ID: Reset the system. Cycled 3 wafers using the Deep recipe with no problems. Backside He flow is ~ 2.4 sccm for all 3 wafers. From eenriquez at snf.stanford.edu Fri May 1 09:53:38 2009 From: eenriquez at snf.stanford.edu (eenriquez at snf.stanford.edu) Date: Fri, 1 May 2009 09:53:38 -0700 Subject: Comment stsetch SNF 2009-05-01 00:33:34: computer problem solved, now He problem Message-ID: Reset the system. Cycled 3 wafers using the Deep recipe with no problems. Backside He flow is ~ 2.4 sccm for all 3 wafers. From bchui at snf.stanford.edu Fri May 8 22:59:38 2009 From: bchui at snf.stanford.edu (bchui at snf.stanford.edu) Date: Fri, 8 May 2009 22:59:38 -0700 Subject: Problem stsetch SNF 2009-05-08 22:59:37: Wafer frag inside chamber Message-ID: When I unloaded my first wafer tonight, I found that a 10x20mm piece had broken off, presumably still inside the chamber. But I couldn't see it with a flashlight or even with the plasma on. He flow/pressure and power are normal. In view of this, I thought I won't red-light the machine and spoil it for others over the weekend, but rather let maintenance retrieve the fragment at their convenience. Sorry for causing the problem. From jwpchen at snf.stanford.edu Tue May 12 15:32:42 2009 From: jwpchen at snf.stanford.edu (jwpchen at snf.stanford.edu) Date: Tue, 12 May 2009 15:32:42 -0700 Subject: Problem stsetch SNF 2009-05-12 15:32:41: SF6 flow questionable Message-ID: Observed severe grassing on DEEP recipe, that gave nil grass before on the same geometry. Went and did a pressure vs flow sweep for SF6. The results are quite linear, except the intercept is ~16mTorr! (for extrapolated zero flow) In contrast, the C4F8 flow intercepts at near 0mTorr. From eenriquez at snf.stanford.edu Thu May 14 13:26:09 2009 From: eenriquez at snf.stanford.edu (eenriquez at snf.stanford.edu) Date: Thu, 14 May 2009 13:26:09 -0700 Subject: Comment stsetch SNF 2009-05-14 13:26:09: SF6 flow update Message-ID: Preliminary tests shows that the actual SF6 flow can be as much as 2X more than what is indicated on the screen. The flow however has been stable at this level for over 1 year. Corrective action plan: 1) Order a new calibrated SF6 MFC (5/15) 2) Verify the actual gas flow of all the gases using an external calibrated mass flow meter. (5/20) 3) Run process quals (5/20 ?) 4) Troubleshoot cause of flow deviation (5/20) 5) Inform the STSetcher user community of possible changes (5/22) 6) If MFC is found to be defective; replace the SF6 MFC (6/1) 7) Run process quals (6/1 ?) From quickwin at snf.stanford.edu Sun May 17 09:34:53 2009 From: quickwin at snf.stanford.edu (quickwin at snf.stanford.edu) Date: Sun, 17 May 2009 09:34:53 -0700 Subject: Problem stsetch SNF 2009-05-17 09:34:52: chamber may need cleaning Message-ID: I have etched some 6 wafers and something looks strange. It takes longer to etch away the bottom of the holes, the etch mask color looks very different from what it should be, and even the color of the SF6 plasma looks a little darker than normal. I did a 30 minute O2 clean and it seems to help a little. This may be related to what jwpchen reported (grass formation in DEEP program). I suggest opening the chamber immediately and do a quick cleaning of the chamber. From ericp at snf.stanford.edu Sun May 17 20:20:00 2009 From: ericp at snf.stanford.edu (ericp at snf.stanford.edu) Date: Sun, 17 May 2009 20:20:00 -0700 Subject: Comment stsetch SNF 2009-05-17 20:19:59: broken wafer cleared, fixed lifter pin problem Message-ID: Mislam had a wafer break for no apparent reason (clean break, only two pieces) . I cleared that wafer, and he ran a test, and that wafer broke on loading (brand new oxidized wafer). On further inspection, the lifter pin was sticking up out of the chuck by a fraction of a mm. (You could feel it running your finger over it.). I cleaned a pile of wafer dust out from under the lift pin, and that problem appears to be solved. I also vacuumed out many wafers worth of chips at the bottom. We need to be careful to get ALL the junk out when a wafer breaks, and check for the lifter pin problem. It's a real pain (especially solo) to clean the cavity under the lifter pin, but it has to be done or people's wafers start breaking. Chamber base pressure is now 0.0 mT, and leak rate is <1mT (loadlock pumped). I changed a few of the plastic screwcaps that were punched through, or nearly so. It would be good to order more plastic caps, as we are running low. From latta at snf.stanford.edu Tue May 19 16:39:47 2009 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Tue, 19 May 2009 16:39:47 -0700 Subject: Problem stsetch SNF 2009-05-08 22:59:37: Wafer frag inside chamber Message-ID: Ericp cleaned up chamber From bchui at snf.stanford.edu Tue May 19 17:08:35 2009 From: bchui at snf.stanford.edu (bchui at snf.stanford.edu) Date: Tue, 19 May 2009 17:08:35 -0700 Subject: Problem stsetch SNF 2009-05-19 17:08:35: Wafer fragment inside chamber Message-ID: A fragment broke off my wafer and it's sitting on top of the chuck and the O-ring, so I can't run the machine anymore. From bchui at snf.stanford.edu Tue May 19 18:31:17 2009 From: bchui at snf.stanford.edu (bchui at snf.stanford.edu) Date: Tue, 19 May 2009 18:31:17 -0700 Subject: Comment stsetch SNF 2009-05-19 18:31:16: Fragment retrieved Message-ID: Machine is in operational state again. From bchui at snf.stanford.edu Wed May 20 16:01:18 2009 From: bchui at snf.stanford.edu (bchui at snf.stanford.edu) Date: Wed, 20 May 2009 16:01:18 -0700 Subject: Shutdown stsetch SNF 2009-05-20 16:01:16: Wafer broke inside chamber Message-ID: Wafer broke inside chamber From cbaxter at snf.stanford.edu Wed May 20 16:53:26 2009 From: cbaxter at snf.stanford.edu (cbaxter at snf.stanford.edu) Date: Wed, 20 May 2009 16:53:26 -0700 Subject: Shutdown stsetch SNF 2009-05-20 16:01:16: Wafer broke inside chamber Message-ID: Cleaned up broken wafer chips and run o2 clean.. From eenriquez at snf.stanford.edu Wed May 20 18:50:46 2009 From: eenriquez at snf.stanford.edu (eenriquez at snf.stanford.edu) Date: Wed, 20 May 2009 18:50:46 -0700 Subject: Comment stsetch SNF 2009-05-20 18:50:45: SF6 flow check Message-ID: Check MFC flows using a calibrated flow meter. SF6 MFC: set point = 130 sccm, actual = 213 sccm set point = 45 sccm, actual = 130 sccm C4F8 MFC: set point = 85 sccm, actual = 86 sccm From quickwin at snf.stanford.edu Thu May 21 09:38:19 2009 From: quickwin at snf.stanford.edu (quickwin at snf.stanford.edu) Date: Thu, 21 May 2009 09:38:19 -0700 Subject: Problem stsetch SNF 2009-05-21 09:38:18: reducing SF6 flow did not work Message-ID: Hi all, Because of the talk about the SF6 MFC giving too much flow, I set my program so that SF6 flow was half the value before (from 130 sccm to 65 sccm). The result: completely charred wafer. So, think twice before you try the same approach to solve the current SF6 problem. From bchui at snf.stanford.edu Tue May 26 03:24:20 2009 From: bchui at snf.stanford.edu (bchui at snf.stanford.edu) Date: Tue, 26 May 2009 03:24:20 -0700 Subject: Comment stsetch SNF 2009-05-26 03:24:20: Re: SF6 adjustment Message-ID: I tried reducing the SF6 from 130 to 100 and the etch went very well... nice etch profile, nearly vertical sidewalls and nice selectivity. From mtang at snf.stanford.edu Thu May 28 09:23:31 2009 From: mtang at snf.stanford.edu (mtang at snf.stanford.edu) Date: Thu, 28 May 2009 09:23:31 -0700 Subject: Problem stsetch SNF 2009-05-28 09:23:31: High reflected power on SF6 cycle Message-ID: Noted in "deep" recipe. This will be addressed along with SF6 MFC change on Tuesday. From bchui at snf.stanford.edu Sat May 30 01:18:59 2009 From: bchui at snf.stanford.edu (bchui at snf.stanford.edu) Date: Sat, 30 May 2009 01:18:59 -0700 Subject: Problem stsetch SNF 2009-05-30 01:18:58: Interlock tripped error Message-ID: Arrived to use machine, found "interlock tripped error" occurred on previous user's wafer. Previous user's wafer still inside chamber; machine won't let me unload. From bchui at snf.stanford.edu Sun May 31 15:39:39 2009 From: bchui at snf.stanford.edu (bchui at snf.stanford.edu) Date: Sun, 31 May 2009 15:39:39 -0700 Subject: Shutdown stsetch SNF 2009-05-31 15:39:39: Interlock tripped error Message-ID: Another user tried to use the machine and got the same error, so it's not just a glitch that can be fixed with a soft reset.