From latta at snf.stanford.edu Wed Oct 23 03:08:23 2002 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Oct 23, 2002 3:08:23 PM Subject: Problem tylan4 2002-09-04 15:41:14: see Ty #1 Equip email achieve note on TCA Message-ID: All work completed. From latta at snf.stanford.edu Wed Oct 23 03:14:51 2002 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Oct 23, 2002 3:14:51 PM Subject: Shutdown tylan4 2002-09-24 15:58:30: needs uniformity test. Message-ID: Uniformity test completed. Wafer position L C R T B Avr 1 (front) 1025 1024 1022 1030 1014 1023A 2 1017 1015 1017 1022 1010 1016A 3 1015 1018 1020 1023 1009 1017A 4 back) 1021 1018 1019 1024 1013 1019A From mdickey at snf.stanford.edu Thu Oct 24 02:51:15 2002 From: mdickey at snf.stanford.edu (mdickey at snf.stanford.edu) Date: Oct 24, 2002 2:51:15 PM Subject: Shutdown tylan4 2002-10-24 14:51:12: Pull and clean Message-ID: Tube is down for a pull and clean From mdickey at snf.stanford.edu Fri Oct 25 10:32:12 2002 From: mdickey at snf.stanford.edu (mdickey at snf.stanford.edu) Date: Oct 25, 2002 10:32:12 AM Subject: Comment tylan4 2002-10-25 10:32:11: Ramp up Message-ID: The pull and clean is done. Tube is currently ramping up to temperature From latta at snf.stanford.edu Tue Oct 29 16:18:27 2002 From: latta at snf.stanford.edu (Nancy Latta) Date: Tue, 29 Oct 2002 16:18:27 -0800 Subject: Uniformity results Oct 28 &29 Message-ID: <3DBF2553.FBDA45C3@snf.stanford.edu> Folks, Here are the results from yesterday's and today's WET900 00:39:00 oxidation runs. We've got a problem. Wf pos Center Top Left Bottom Right Oct 28 1 Front 805/1.468 870/1.468 807/1.468 730/1.465 810/1.468 2 848/1.469 914/1.468 863/1.468 778/1.469 846/1.468 3 881/1.469 935/1.468 890/1.468 783/1.468 886/1.469 4 Back 901/1.469 935/1.469 891/1.469 858/1.469 913/1.469 Oct 29 1 Front 734/1.464 826/1.466 737/1.465 649/1.464 763/1.464 2 798/1.466 891/1.467 804/1.465 690/1.463 818/1.466 3 836/1.467 897/1.467 840/1.465 730/1.464 856/1.467 4 Back 856/1.466 898/1.466 850/1.466 802/1.466 851/1.466 -- -- Nancy Latta Stanford Nanofabrication Facility CIS Room 145 420 Via Palou Mall Stanford, CA 94305-4070 (650) 725-6727 latta at snf.stanford.edu From latta at snf.stanford.edu Tue Oct 29 16:21:53 2002 From: latta at snf.stanford.edu (Nancy Latta) Date: Tue, 29 Oct 2002 16:21:53 -0800 Subject: Uniformity results Sept 26, tylan2 & 4 Message-ID: <3DBF2621.CBE56C87@snf.stanford.edu> For historical reasons I am adding the runs done earlier this and last month. Please note, they are for WET900 00:42:00 and the measurements were done on nanospec. Folks, Today I was able to run unifomity checks using Jim's recommended WET900 program. Both tubes were run with the same program for the same time (42mins) at the same time. The results, below, are interesting. The data is displayed with the front wafer first and the spread was over two boats per tube, positioned identically; Wf position Center Top Bottom Right Left Average Tylan2 1 (front) 1061 1063 1058 1062 1061 1061A 2 1064 1066 1060 1067 1062 1064A 3 1072 1074 1069 1074 1070 1072A 4 (back) 1087 1091 1084 1090 1081 1087A Tylan4 1 (front) 847 869 822 854 854 849A 2 871 884 854 879 876 873A 3 883 890 868 886 880 881A 4 (back) 889 893 883 889 891 889A -- Nancy Latta Stanford Nanofabrication Facility CIS Room 145 420 Via Palou Mall Stanford, CA 94305-4070 (650) 725-6727 latta at snf.stanford.edu From latta at snf.stanford.edu Tue Oct 29 16:25:11 2002 From: latta at snf.stanford.edu (Nancy Latta) Date: Tue, 29 Oct 2002 16:25:11 -0800 Subject: Wet & Dry Ox results, Oct 1 Message-ID: <3DBF26E7.951FC92C@snf.stanford.edu> Folks, Again, for comparison reasons, here are the previous wet and dry ox measurements, again measured on nanospec. ------------------------------------------------------------------------- Folks, Here is the data for the last two runs I did in tylan4. Dry ox was run first followed by wet ox the next day. Before either program was run Ray checked the temp profile for tylan4. Jim and Ray were available to check the temp readings during the wet ox. They are within 1-2 degrees of the tycom read out. Wf position Center Top Bottom Right Left Average Dry Ox DRY1000 03:10:00 1 (front) 1164 1153 1160 1164 1168 1162A 2 1157 1156 1158 1158 1156 1157A 3 1154 1154 1151 1155 1151 1153A 4 (back) 1144 1145 1140 1145 1145 1144A Wet Ox WET900 00:42:00 1 (front) 871 884 840 873 875 869A 2 880 895 866 890 875 881A 3 890 898 877 894 891 890A 4 (back) 892 898 885 894 892 892A Please note that the WET900 results track closely with the reults of the run on 9/26/02. This is after the temp profile was checked. -- Nancy Latta Stanford Nanofabrication Facility CIS Room 145 420 Via Palou Mall Stanford, CA 94305-4070 (650) 725-6727 latta at snf.stanford.edu From shott at snf.stanford.edu Tue Oct 29 17:17:49 2002 From: shott at snf.stanford.edu (John Shott) Date: Tue, 29 Oct 2002 17:17:49 -0800 Subject: Uniformity results Oct 28 &29 References: <3DBF2553.FBDA45C3@snf.stanford.edu> Message-ID: <3DBF333D.13DA4B8B@snf.stanford.edu> Nancy et al: Nancy, thanks for collecting and posting this information ... Yes, this doesn't look good ... in fact, I would say that it is rather unusual to see an oxidation with that much variation! There are two disturbing things (over and above the fact that the average overall thickness isn't as great as it should be ...): 1. The top to bottom uniformity on each wafer really stinks. In fact, I don't think that this is easily explained by cantilever position in the same way that it would be in a LPCVD situation. To me, particularly given the fact that these two runs are just after a tube pull, this is a symptom of a temperature uniformity problem. The first thing that I would ask, would be: was all thermal blocking/glass wool installed properly ... I'm thinking that maybe we are drawing air out the vestibule that is being drawn along the length of the tube by leakage near one side of the tube. If cool air is flowing along the one side of the tube (and not along the other), this could affect the top to bottom uniformity. Also, are the spike thermocouples positioned properly and in good thermal contact? 2. We seem to see a pretty significant increase in thickness near the torch end of the tube. This would lead me to think that we don't have a set of calibration numbers that are properly set for the "torch on" condition. Can we double check this? Lastly, I'm a bit surprised that when we saw these problem yesterday ... particularly a top to bottom uniformity problem ... that a more comprehensive search wasn't launched at that point. As I understand it, the conjecture was that a door interlock problem was at fault ... can anyone explain to me how a door interlock can affect top to bottom uniformity? I think that we probably wasted a day re-running an experiment that was bound to produce bad results again today .... Thanks, John From shott at snf.stanford.edu Wed Oct 30 08:08:47 2002 From: shott at snf.stanford.edu (John Shott) Date: Wed, 30 Oct 2002 08:08:47 -0800 Subject: [Fwd: Uniformity results Oct 28 &29] Message-ID: <3DC0040F.F931F623@snf.stanford.edu> Friends of Tylan 4: Keith has been following the saga of tylan 4 and has sent me the following message related to the health/alignment of the torch assembly. He points out that torch problems can result in non-uniform wet oxide thickness ... but should show uniform dry oxidation results. As the tube was just pulled/cleaned can anyone comment on the alignment or wear of the torch assembly? Thanks, John Here are Keith's comments ... John, Nancy - I hope you don't mind me chiming in but I thought of another possibility. Has there been a uniformity test done on this tube with a dry oxidation lately? Were the results better than the wet? If so and the results are better this more than likely points to a faulty or mis-aligned torch. If the center bore of the torch is mis-aligned with the outer bore the flame produced will not be uniform and will cause uniformity variations. (Thicker where the flame is actually pointing). I know there is a baffle in the rear of the tube that is supposed to take care of this problem but doesn't always do it. A dry ox test run would take this variable (steam) out of the equation but would point out any temperature variations. My guess is the dry ox is probably good and you need to replace the torch with one that is properly aligned or not worn. (I would always visibly check the torches to make sure the center bore was aligned with the outer) Hope this helps - Keith -------------- next part -------------- An embedded message was scrubbed... From: Keith Gaul Subject: Re: Uniformity results Oct 28 &29 Date: Wed, 30 Oct 2002 07:34:57 -0800 Size: 3880 URL: From tberg at snf.stanford.edu Wed Oct 30 08:44:36 2002 From: tberg at snf.stanford.edu (Ted Berg) Date: Wed, 30 Oct 2002 08:44:36 -0800 Subject: [Fwd: Uniformity results Oct 28 &29] References: <3DC0040F.F931F623@snf.stanford.edu> Message-ID: <3DC00C74.2B90D937@snf.stanford.edu> John, JUst an update on what we have done this morning. Tube 4 Oxidation Issues This morning we did the following: ? checked the packing-it looked tight but we pushed it in farther. ? Measured the quartz position on three tubes and set the position of # 4 equal to #2 ? Checked all TC positions- all looked fine ? Closed the damper to the position it was for the pre-tube clean Additional info: ? The torch was replaced during the tube pull for possible contamination issues. It was pulled this morning and inspected no visual defects ? John Shott wrote: > Friends of Tylan 4: > > Keith has been following the saga of tylan 4 and has sent me the following > message related to the health/alignment of the torch assembly. He points out > that torch problems can result in non-uniform wet oxide thickness ... but > should show uniform dry oxidation results. > > As the tube was just pulled/cleaned can anyone comment on the alignment or > wear of the torch assembly? > > Thanks, > > John > > Here are Keith's comments ... > > John, Nancy - > I hope you don't mind me chiming in but I thought of another possibility. > Has > there been a uniformity test done on this tube with a dry oxidation lately? > Were > the results better than the wet? If so and the results are better this more > than > likely points to a faulty or mis-aligned torch. If the center bore of the > torch is > mis-aligned with the outer bore the flame produced will not be uniform and > will > cause uniformity variations. (Thicker where the flame is actually pointing). I > know there is a baffle in the rear of the tube that is supposed to take care > of > this problem but doesn't always do it. A dry ox test run would take this > variable > (steam) out of the equation but would point out any temperature variations. My > guess is the dry ox is probably good and you need to replace the torch with > one > that is properly aligned or not worn. (I would always visibly check the > torches to > make sure the center bore was aligned with the outer) > Hope this helps - > Keith > > ------------------------------------------------------------------------ > > Subject: Re: Uniformity results Oct 28 &29 > Date: Wed, 30 Oct 2002 07:34:57 -0800 > From: Keith Gaul > To: John Shott > References: <3DBF2553.FBDA45C3 at snf.stanford.edu> <3DBF333D.13DA4B8B at snf.stanford.edu> > > John, Nancy - > I hope you don't mind me chiming in but I thought of another possibility. Has > there been a uniformity test done on this tube with a dry oxidation lately? Were > the results better than the wet? If so and the results are better this more than > likely points to a faulty or mis-aligned torch. If the center bore of the torch is > mis-aligned with the outer bore the flame produced will not be uniform and will > cause uniformity variations. (Thicker where the flame is actually pointing). I > know there is a baffle in the rear of the tube that is supposed to take care of > this problem but doesn't always do it. A dry ox test run would take this variable > (steam) out of the equation but would point out any temperature variations. My > guess is the dry ox is probably good and you need to replace the torch with one > that is properly aligned or not worn. (I would always visibly check the torches to > make sure the center bore was aligned with the outer) > Hope this helps - > Keith > > John Shott wrote: > > > Nancy et al: > > > > Nancy, thanks for collecting and posting this information ... > > > > Yes, this doesn't look good ... in fact, I would say that it is rather unusual > > to see an oxidation with that much variation! > > > > There are two disturbing things (over and above the fact that the average > > overall thickness isn't as great as it should be ...): > > > > 1. The top to bottom uniformity on each wafer really stinks. In fact, I don't > > think that this is easily explained by cantilever position in the same way > > that it would be in a LPCVD situation. To me, particularly given the fact > > that these two runs are just after a tube pull, this is a symptom of a > > temperature uniformity problem. The first thing that I would ask, would be: > > was all thermal blocking/glass wool installed properly ... I'm thinking that > > maybe we are drawing air out the vestibule that is being drawn along the > > length of the tube by leakage near one side of the tube. If cool air is > > flowing along the one side of the tube (and not along the other), this could > > affect the top to bottom uniformity. Also, are the spike thermocouples > > positioned properly and in good thermal contact? > > > > 2. We seem to see a pretty significant increase in thickness near the torch > > end of the tube. This would lead me to think that we don't have a set of > > calibration numbers that are properly set for the "torch on" condition. Can > > we double check this? > > > > Lastly, I'm a bit surprised that when we saw these problem yesterday ... > > particularly a top to bottom uniformity problem ... that a more comprehensive > > search wasn't launched at that point. As I understand it, the conjecture was > > that a door interlock problem was at fault ... can anyone explain to me how a > > door interlock can affect top to bottom uniformity? I think that we probably > > wasted a day re-running an experiment that was bound to produce bad results > > again today .... > > > > Thanks, > > > > John -------------- next part -------------- An HTML attachment was scrubbed... URL: From shott at snf.stanford.edu Wed Oct 30 09:33:32 2002 From: shott at snf.stanford.edu (John Shott) Date: Wed, 30 Oct 2002 09:33:32 -0800 Subject: [Fwd: Uniformity results Oct 28 &29] References: <3DC0040F.F931F623@snf.stanford.edu> <3DC00C74.2B90D937@snf.stanford.edu> Message-ID: <3DC017EC.360F1B93@snf.stanford.edu> Ted: Have measurements been done to indicate that the spike thermocouples are closer to the in-tube thermocouples than they appeared to be when Jim McVittie measured them last night? We certainly have to have some hardware problem to result in uniformity as bad as we have seen for the last couple of days but, if I interpret your comments correctly, nothing has been found to be out of order. Am I correct in interpeting this as we still don't know what is wrong? Thanks, John > This morning we did the following: > ? checked the packing-it looked tight but we pushed it in farther. > ? Measured the quartz position on three tubes and set the position of # 4 equal to #2 > ? Checked all TC positions- all looked fine > ? Closed the damper to the position it was for the pre-tube clean > Additional info: > ? The torch was replaced during the tube pull for possible contamination issues. It was pulled this morning and > inspected no visual defects From latta at snf.stanford.edu Wed Oct 30 03:23:27 2002 From: latta at snf.stanford.edu (latta at snf.stanford.edu) Date: Oct 30, 2002 3:23:27 PM Subject: Problem tylan4 2002-10-30 15:23:26: Ox test results Message-ID: It's not the injector Again, WET900, 00:39:00, measured by ellipsometer Wf Center Bottom Right Top Left Front 819/1.468 747/1.468 850/1.469 900/1.469 809/1.467 #2 866/1.469 817/1.469 858/1.468 918/1.468 885/1.467 #3 893/1.468 819/1.468 882/1.468 939/1.468 911/1.468 Back 906/1.469 869/1.469 894/1.469 938/1.468 919/1.468 From latta at snf.stanford.edu Thu Oct 31 15:12:27 2002 From: latta at snf.stanford.edu (Nancy Latta) Date: Thu, 31 Oct 2002 15:12:27 -0800 Subject: Results of Dry ox Message-ID: <3DC1B8DB.207FD8C1@snf.stanford.edu> Folks, Below are the results of the Dry ox run, DRY1100, 01:05:00. Wf C B R T L #1F 1341/1.458 1341/1.458 1339/1.458 1338/1.458 1340/1.458 #2 1332/1.458 1331/1.458 1331/1.458 1333/1.458 1333/1.458 #3 1328/1.458 1325/1.458 1326/1.458 1326/1.458 1327/1.458 #4B 1310/1.458 1311/1.458 1310/1.458 1313/1.458 1314/1.458 (I wish these columns would line up correctly....) -- Nancy Latta Stanford Nanofabrication Facility CIS Room 145 420 Via Palou Mall Stanford, CA 94305-4070 (650) 725-6727 latta at snf.stanford.edu