From shott at snf.stanford.edu Wed Jan 7 18:34:01 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:34:01 -0800 Subject: Problem drytek2 SNF 2008-10-21 11:21:41: RF LED Burned Out Message-ID: Lamp replaced .... From shott at snf.stanford.edu Wed Jan 7 18:38:06 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:38:06 -0800 Subject: Problem drytek2 SNF 2008-10-22 11:49:11: RF power is very low Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:38:14 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:38:14 -0800 Subject: Comment drytek2 SNF 2008-10-29 18:02:56: Update low RF power Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:38:23 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:38:23 -0800 Subject: Problem drytek2 SNF 2008-10-30 11:09:30: RF max'd at 450 Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:38:31 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:38:31 -0800 Subject: Comment drytek2 SNF 2008-10-30 13:50:10: Update low RF power Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:38:40 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:38:40 -0800 Subject: Comment drytek2 SNF 2008-10-30 23:09:18: Max RF is about 350W Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:38:47 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:38:47 -0800 Subject: Comment drytek2 SNF 2008-11-04 13:53:02: Any update on RF power? Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:38:53 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:38:53 -0800 Subject: Comment drytek2 SNF 2008-11-04 22:06:00: RF power Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:39:00 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:39:00 -0800 Subject: Comment drytek2 SNF 2008-11-13 02:36:23: RF power max at 375W with 0 reflected Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:39:07 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:39:07 -0800 Subject: Comment drytek2 SNF 2008-11-18 20:55:31: Process 2 power drifts Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:39:17 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:39:17 -0800 Subject: Comment drytek2 SNF 2008-11-20 15:16:21: Process 1 power also drifting down Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:39:24 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:39:24 -0800 Subject: Problem drytek2 SNF 2008-11-23 16:58:54: plasma does not strike Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:39:37 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:39:37 -0800 Subject: Problem drytek2 SNF 2008-12-05 14:38:59: power inconsistent! Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From shott at snf.stanford.edu Wed Jan 7 18:39:55 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 7 Jan 2009 18:39:55 -0800 Subject: Comment drytek2 SNF 2008-12-06 21:54:13: RF Problems .... Message-ID: I've had limited success in working on the RF power supply ... it's not great, but it will at least hold 500W of power without drooping for 30 minutes. Things changed: replaced both the electrolytics in the +12V and +40V power supplies in the oscillator and first drive stage. Replaced the 2N3866 and MJE2801 transistors in the oscillator stage. Change the emitter degeneration resistor in Q3 to a 1/2W 15 ohm resistor (the 1/4W was margina). Replaced the 741 op amp. So, modest improvements .... but no smoking gun that restored full 1000W power. John From latta at snf.stanford.edu Thu Jan 8 12:21:58 2009 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Thu, 8 Jan 2009 12:21:58 -0800 Subject: Problem drytek2 SNF 2009-01-08 12:21:58: RF drifting Message-ID: I ran Process 2 (poly etch, 400W) for 10 mins. At about 3 mins the RF drifted to 375. By continuing to crank up on FR Level pot I kept it at 375W . Additional 2 min etches drifted a bit also, but I was able to keep them at 400W by monitoring the power. From latta at snf.stanford.edu Fri Jan 9 10:58:38 2009 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Fri, 9 Jan 2009 10:58:38 -0800 Subject: Problem drytek2 SNF 2008-11-26 02:49:21: Reflected Power ~200W for O2 clean (Descum) Message-ID: tuning for O2 plasma gates to about 40W refl now From latta at snf.stanford.edu Fri Jan 9 10:59:12 2009 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Fri, 9 Jan 2009 10:59:12 -0800 Subject: Problem drytek2 SNF 2008-12-03 22:19:00: high reflection power and no forward power Message-ID: After John's fix power is back, but needs monitoring. From latta at snf.stanford.edu Fri Jan 9 10:59:50 2009 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Fri, 9 Jan 2009 10:59:50 -0800 Subject: Comment drytek2 SNF 2008-12-04 08:32:05: Update high reflected power Message-ID: Still in that condition- to the archives From latta at snf.stanford.edu Fri Jan 9 11:00:18 2009 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Fri, 9 Jan 2009 11:00:18 -0800 Subject: Comment drytek2 SNF 2008-12-06 11:16:03: Process 2 RF level knob has little if any effect Message-ID: Better now, but still drifts a bit over time. From latta at snf.stanford.edu Fri Jan 9 11:06:13 2009 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Fri, 9 Jan 2009 11:06:13 -0800 Subject: Comment drytek2 SNF 2009-01-09 11:06:13: Process Qual after RF repair Message-ID: Poly Etch Recipe used, Si is poly layer- etch rates and selectivities are the average of all six electrodes. Suggested that labmembers use electrodes 3 through 6 as 1 and 2 etch slower (#1) or faster (#2) than the others. Full data available on request. Poly ER = 1852A/min PR ER = 312A/min Th Ox ER = 143A/min Sel SI : PR = 6 : 1 Sel Si : Ox = 13 : 1 From yeh at snf.stanford.edu Tue Jan 13 11:29:46 2009 From: yeh at snf.stanford.edu (yeh at snf.stanford.edu) Date: Tue, 13 Jan 2009 11:29:46 -0800 Subject: Problem drytek2 SNF 2009-01-13 11:29:45: RF Power still drifting Message-ID: Ran descum (process #1) 4 times. Power drifts, normally downwards, in range from 500W to 375W with a constant 40W reflection. Power maxes out at 500W. From shott at snf.stanford.edu Wed Jan 14 07:32:16 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 14 Jan 2009 07:32:16 -0800 Subject: Shutdown drytek2 SNF 2009-01-14 07:32:15: Shutting down to work on matching network ... Message-ID: From shott at snf.stanford.edu Wed Jan 14 08:24:03 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 14 Jan 2009 08:24:03 -0800 Subject: Shutdown drytek2 SNF 2009-01-14 07:32:15: Shutting down to work on matching network ... Message-ID: Didn't make any real changes but made some measurements in preparation for when I have a bit more access to the tool. John From lindaw at snf.stanford.edu Wed Jan 14 12:29:13 2009 From: lindaw at snf.stanford.edu (lindaw at snf.stanford.edu) Date: Wed, 14 Jan 2009 12:29:13 -0800 Subject: Problem drytek2 SNF 2009-01-14 12:29:12: power & tuning unstable process 1&2 Message-ID: process 1 O2 descum, forward power ~200 W. By turning cap clockwise, can get forward power to spike to ~600, but reflected is high. turning cap counter clockwise slowly reduces the reflected to about 80 W while maintaining forward power at 500W, but if I keep turning cap ccw to further reduce reflected power, the forward power drops back off to 200W. Similar tuning issues with process 2 poly etch. I get one set of wafers tuned and stable at 400W forward and 40W reflected. When I load a second set of similar wafers, the tuning is way off, 200W forward, 140 reflected. Adjusting the coil has no effect, but turning the cap clockwise to get forward power spike to 400W, and then backing the cap off ccw to reduce the reflected down to 40W seems to bring tuning back to a stable state. The power supply is WHACK! From yeh at snf.stanford.edu Thu Jan 15 11:59:38 2009 From: yeh at snf.stanford.edu (yeh at snf.stanford.edu) Date: Thu, 15 Jan 2009 11:59:38 -0800 Subject: Problem drytek2 SNF 2009-01-15 11:59:37: RF level knob Message-ID: has little effect on forward power. o2 descum process 1. From yeh at snf.stanford.edu Tue Jan 20 08:50:24 2009 From: yeh at snf.stanford.edu (yeh at snf.stanford.edu) Date: Tue, 20 Jan 2009 08:50:24 -0800 Subject: Problem drytek2 SNF 2009-01-20 08:50:23: RF power still drifting Message-ID: process1, RF power drifts fm 550 to 350W w/i 2min. RF level kknob maxed out. From shott at snf.stanford.edu Wed Jan 21 11:40:10 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 21 Jan 2009 11:40:10 -0800 Subject: Shutdown drytek2 SNF 2009-01-21 11:40:09: Matching network upgrade .... Message-ID: Shutting down to upgrade matching network components. Adding 200 pF of fixed capacitance (to total 800 pf) in parallel with the 0-500 pf variable capacitor. Also reducing the fixed inductor in parallel with the 0-4 uH roller inductor. I have 2 fixed inductors to try .... John From shott at snf.stanford.edu Wed Jan 21 15:32:23 2009 From: shott at snf.stanford.edu (shott at snf.stanford.edu) Date: Wed, 21 Jan 2009 15:32:23 -0800 Subject: Shutdown drytek2 SNF 2009-01-21 11:40:09: Matching network upgrade .... Message-ID: Added 200 pf of fixed capacitance and placed the smaller of the two hand-wound inductors in paralled with the roller inductor. This was the 2-turn inductor made by wrapping 1/4" copper tubing around a piece of 1 1/4" Schedule 80 PVC pipe. The separation between adjacent loops is about 1/4 inch as well. This improved tuning performance. I was able to comfortably tune an oxygen plasma with a coil setting of 1.6 and a capacitor setting of about 2.2. If anything, I may have increased the capacitance too much ... and should consider removing 50-100 pf in the future. When tuning I saw a forward power of 425 watts and could consistently achieve a reflected power of 20 watts or less. Note: I measured my new fixed inductor to be 670 nH, my larger inductor was about 840 nH (both measured with the HP 4275 LCR meter with a small signal frequency of 1MHz. The reading was fairly independent of frequency. John From lindaw at snf.stanford.edu Thu Jan 22 16:14:22 2009 From: lindaw at snf.stanford.edu (lindaw at snf.stanford.edu) Date: Thu, 22 Jan 2009 16:14:22 -0800 Subject: Problem drytek2 SNF 2009-01-22 16:14:22: proc. 2 poly max power 300W min refl. 80W Message-ID: Can't tune process 2 poly etch to better than 300 W forward with 80 W reflected. Earlier today I was able to get 375-350 W forward with 40 reflected. used same settings, and now can't get anywhere near that. From lindaw at snf.stanford.edu Fri Jan 23 10:29:28 2009 From: lindaw at snf.stanford.edu (lindaw at snf.stanford.edu) Date: Fri, 23 Jan 2009 10:29:28 -0800 Subject: Comment drytek2 SNF 2009-01-23 10:29:28: Process2 poly etch Message-ID: The best i could get the tuning today was coil = 172, cap = 602 forward power 350W, reflected power 40 W. Power knob at max power.