From mtang at snf.stanford.edu Tue Sep 7 14:37:05 2004 From: mtang at snf.stanford.edu (Mary Tang) Date: Tue, 07 Sep 2004 14:37:05 -0700 Subject: Breaking wafers? Message-ID: <413E2A01.F2269A67@snf.stanford.edu> Hi everyone -- "rosti" dropped by my office to say that he was thinking about using the wafersaw, but was concerned about a problem he had experienced a couple of times in which the saw BROKE his wafer. He says that instead of starting on the edge, in these instances, the saw blade dropped onto the middle of the wafer and thus broke his wafers. The last instance that he observed was some time back last October or so. Now I'm worried! Usually, when a wafer is ready for dicing, you've expended a lot of time and energy into it -- you simply can't afford to have it smashed. I'm also really concerned because I've been training on the wafersaw for a couple of years now, but have not observed this problem nor had I heard about it from anyone (and here I thought I knew all the machine's quirks). I had heard that it used to be a problem, but not seen since the system was basically rebuilt a few years ago. Now, I'm hearing otherwise... Has anyone else had this problem? If so, could you let me know approximately when it happened and how often (if you were "lucky", like rosti, and got hit more than once?) And maybe even the circumstances when it occurred (if you remember). Your feedback will help us decide what to do (if the darned thing is breaking wafers intermittently, we may need to take it off-line...) And, most importantly, if you observe this or any other problem, please, please, please report it on Coral! (I'm going back several years, and don't happen to see anything about the machine breaking wafers...) Thanks, Mary -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From alan.m.myers at intel.com Tue Sep 7 14:50:49 2004 From: alan.m.myers at intel.com (Myers, Alan M) Date: Tue, 7 Sep 2004 14:50:49 -0700 Subject: Breaking wafers? Message-ID: <8A3152FDE2948B42AECCF93BFFA130EC02601F26@scsmsx401.amr.corp.intel.com> Mary, I used to have this problem every time I use the saw. I learned the secret is to set the wafer diameter 200 mm whenever I get near the top of the wafer. It may take a little longer, but at least the blades and the wafers remain intact. Alan -----Original Message----- From: Mary Tang [mailto:mtang at snf.stanford.edu] Sent: Tuesday, September 07, 2004 2:37 PM To: wafersaw at snf.stanford.edu Cc: rcrane; Paul Rissman; jhaydon Subject: Breaking wafers? Hi everyone -- "rosti" dropped by my office to say that he was thinking about using the wafersaw, but was concerned about a problem he had experienced a couple of times in which the saw BROKE his wafer. He says that instead of starting on the edge, in these instances, the saw blade dropped onto the middle of the wafer and thus broke his wafers. The last instance that he observed was some time back last October or so. Now I'm worried! Usually, when a wafer is ready for dicing, you've expended a lot of time and energy into it -- you simply can't afford to have it smashed. I'm also really concerned because I've been training on the wafersaw for a couple of years now, but have not observed this problem nor had I heard about it from anyone (and here I thought I knew all the machine's quirks). I had heard that it used to be a problem, but not seen since the system was basically rebuilt a few years ago. Now, I'm hearing otherwise... Has anyone else had this problem? If so, could you let me know approximately when it happened and how often (if you were "lucky", like rosti, and got hit more than once?) And maybe even the circumstances when it occurred (if you remember). Your feedback will help us decide what to do (if the darned thing is breaking wafers intermittently, we may need to take it off-line...) And, most importantly, if you observe this or any other problem, please, please, please report it on Coral! (I'm going back several years, and don't happen to see anything about the machine breaking wafers...) Thanks, Mary -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From mtang at snf.stanford.edu Tue Sep 7 15:06:22 2004 From: mtang at snf.stanford.edu (Mary Tang) Date: Tue, 07 Sep 2004 15:06:22 -0700 Subject: Breaking wafers? References: <8A3152FDE2948B42AECCF93BFFA130EC02601F26@scsmsx401.amr.corp.intel.com> Message-ID: <413E30DE.1013DB70@snf.stanford.edu> Thanks, I'd absolutely no idea about this. I'd been told (by Len, the saw expert) that setting the diameter larger was helpful for the occasional problem in which the saw didn't cut all the way across, but maybe this is related to starting in the middle... This is easy to do in principle, but does mean we wouldn't be able to take advantage of a slow entry speed (though perhaps small insurance against breaking wafers...) I'll try it out and see if I can likewise induce/cure the problem. And unless I hear otherwise, I'll plan on adding Alan's method to the operating procedures and training... Mary "Myers, Alan M" wrote: > Mary, > I used to have this problem every time I use the saw. I learned the secret is to set the wafer diameter 200 mm whenever I get near the top of the wafer. It may take a little longer, but at least the blades and the wafers remain intact. > > Alan > > -----Original Message----- > From: Mary Tang [mailto:mtang at snf.stanford.edu] > Sent: Tuesday, September 07, 2004 2:37 PM > To: wafersaw at snf.stanford.edu > Cc: rcrane; Paul Rissman; jhaydon > Subject: Breaking wafers? > > Hi everyone -- > > "rosti" dropped by my office to say that he was thinking about using the > wafersaw, but was concerned about a problem he had experienced a couple > of times in which the saw BROKE his wafer. He says that instead of > starting on the edge, in these instances, the saw blade dropped onto the > middle of the wafer and thus broke his wafers. The last instance that > he observed was some time back last October or so. > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > expended a lot of time and energy into it -- you simply can't afford to > have it smashed. I'm also really concerned because I've been training > on the wafersaw for a couple of years now, but have not observed this > problem nor had I heard about it from anyone (and here I thought I knew > all the machine's quirks). I had heard that it used to be a problem, > but not seen since the system was basically rebuilt a few years ago. > Now, I'm hearing otherwise... > > Has anyone else had this problem? If so, could you let me know > approximately when it happened and how often (if you were "lucky", like > rosti, and got hit more than once?) And maybe even the circumstances > when it occurred (if you remember). Your feedback will help us decide > what to do (if the darned thing is breaking wafers intermittently, we > may need to take it off-line...) > > And, most importantly, if you observe this or any other problem, please, > please, please report it on Coral! (I'm going back several years, and > don't happen to see anything about the machine breaking wafers...) > > Thanks, > > Mary > > -- > Mary X. Tang, Ph.D. > Stanford Nanofabrication Facility > CIS Room 136, Mail Code 4070 > Stanford, CA 94305 > (650)723-9980 > mtang at stanford.edu > http://snf.stanford.edu -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From mtang at snf.stanford.edu Wed Sep 8 14:18:39 2004 From: mtang at snf.stanford.edu (Mary Tang) Date: Wed, 08 Sep 2004 14:18:39 -0700 Subject: [Fwd: Re: Breaking wafers?] Message-ID: <413F772F.2B468EE4@snf.stanford.edu> Hi everyone! Thanks for your inputs! I think Karl has provided the historical perspective, and explains why a larger diameter is useful. So, I'll change the operating procedure to reflect these inputs (with the recommendation to run at 150 mm, whatever the substrate size, recognizing that this negates the entry speed feature). By the way, this morning I tried using 200 mm as suggested by some, but it seems that the stage sometimes gets stuck because it's hit a limit switch - so based on this, I think 150 mm might be better (please let me know if your experience suggests otherwise!) Thanks again -- Mary -------- Original Message -------- Subject: Re: Breaking wafers? Date: Tue, 7 Sep 2004 17:38:15 -0700 (PDT) From: Karl Brandt To: Mary Tang Believe it or not, this was a problem from the first day we got the tool from K&S. After repeated attempts by K&S to resolve it, they finally threw up their hands and said they simply had no idea what was wrong or how to fix it. The accepted workaround has been to set the wafer diameter to some large diameter. -Karl ********************************************************************* Karl Brandt http://people.ucsc.edu/~kbrandt/ On Tue, 7 Sep 2004, Mary Tang wrote: > Hi everyone -- > > "rosti" dropped by my office to say that he was thinking about using the > wafersaw, but was concerned about a problem he had experienced a couple > of times in which the saw BROKE his wafer. He says that instead of > starting on the edge, in these instances, the saw blade dropped onto the > middle of the wafer and thus broke his wafers. The last instance that > he observed was some time back last October or so. > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > expended a lot of time and energy into it -- you simply can't afford to > have it smashed. I'm also really concerned because I've been training > on the wafersaw for a couple of years now, but have not observed this > problem nor had I heard about it from anyone (and here I thought I knew > all the machine's quirks). I had heard that it used to be a problem, > but not seen since the system was basically rebuilt a few years ago. > Now, I'm hearing otherwise... > > Has anyone else had this problem? If so, could you let me know > approximately when it happened and how often (if you were "lucky", like > rosti, and got hit more than once?) And maybe even the circumstances > when it occurred (if you remember). Your feedback will help us decide > what to do (if the darned thing is breaking wafers intermittently, we > may need to take it off-line...) > > And, most importantly, if you observe this or any other problem, please, > please, please report it on Coral! (I'm going back several years, and > don't happen to see anything about the machine breaking wafers...) > > Thanks, > > Mary > > > -- > Mary X. Tang, Ph.D. > Stanford Nanofabrication Facility > CIS Room 136, Mail Code 4070 > Stanford, CA 94305 > (650)723-9980 > mtang at stanford.edu > http://snf.stanford.edu > > From afflannery at comcast.net Wed Sep 8 15:24:24 2004 From: afflannery at comcast.net (afflannery at comcast.net) Date: Wed, 08 Sep 2004 22:24:24 +0000 Subject: [Fwd: Re: Breaking wafers?] Message-ID: <090820042224.14853.413F86970003DD2D00003A052200734076979D0A02020E0400000E@comcast.net> Hi, Just for the record, we've diced about 5 wafers in the last 6 weeks setting the diameter between 105 and 110. We've not had a problem with breaking. I think the reason the blade sets down in the middle of the wafer is that it thinks that it is the top. If you look at the pattern of dicing when this happen, the edges of the incomplete cuts form a circle. I think it gets confused as to its Y location relative to the wafer when you do your alignment on a dicing lane at the edge, not in the center. I may make my first cut at the edge, but I always align to a dicing lane in the center. Just my $0.02, and that's about all it is worth. Tony -------------- Original message -------------- > Hi everyone! > > Thanks for your inputs! I think Karl has provided the historical > perspective, and explains why a larger diameter is useful. So, I'll > change the operating procedure to reflect these inputs (with the > recommendation to run at 150 mm, whatever the substrate size, > recognizing that this negates the entry speed feature). By the way, > this morning I tried using 200 mm as suggested by some, but it seems > that the stage sometimes gets stuck because it's hit a limit switch - so > based on this, I think 150 mm might be better (please let me know if > your experience suggests otherwise!) > > Thanks again -- > > Mary > > > -------- Original Message -------- > Subject: Re: Breaking wafers? > Date: Tue, 7 Sep 2004 17:38:15 -0700 (PDT) > From: Karl Brandt > To: Mary Tang > > > Believe it or not, this was a problem from the first day we got the tool > from K&S. After repeated attempts by K&S to resolve it, they finally > threw > up their hands and said they simply had no idea what was wrong or how to > fix it. The accepted workaround has been to set the wafer diameter to > some > large diameter. > > -Karl > > ********************************************************************* > Karl Brandt > http://people.ucsc.edu/~kbrandt/ > > > On Tue, 7 Sep 2004, Mary Tang wrote: > > > Hi everyone -- > > > > "rosti" dropped by my office to say that he was thinking about using the > > wafersaw, but was concerned about a problem he had experienced a couple > > of times in which the saw BROKE his wafer. He says that instead of > > starting on the edge, in these instances, the saw blade dropped onto the > > middle of the wafer and thus broke his wafers. The last instance that > > he observed was some time back last October or so. > > > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > > expended a lot of time and energy into it -- you simply can't afford to > > have it smashed. I'm also really concerned because I've been training > > on the wafersaw for a couple of years now, but have not observed this > > problem nor had I heard about it from anyone (and here I thought I knew > > all the machine's quirks). I had heard that it used to be a problem, > > but not seen since the system was basically rebuilt a few years ago. > > Now, I'm hearing otherwise... > > > > Has anyone else had this problem? If so, could you let me know > > approximately when it happened and how often (if you were "lucky", like > > rosti, and got hit more than once?) And maybe even the circumstances > > when it occurred (if you remember). Your feedback will help us decide > > what to do (if the darned thing is breaking wafers intermittently, we > > may need to take it off-line...) > > > > And, most importantly, if you observe this or any other problem, please, > > please, please report it on Coral! (I'm going back several years, and > > don't happen to see anything about the machine breaking wafers...) > > > > Thanks, > > > > Mary > > > > > > -- > > Mary X. Tang, Ph.D. > > Stanford Nanofabrication Facility > > CIS Room 136, Mail Code 4070 > > Stanford, CA 94305 > > (650)723-9980 > > mtang at stanford.edu > > http://snf.stanford.edu > > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From erictao at stanford.edu Wed Sep 8 15:31:47 2004 From: erictao at stanford.edu (Eric Tao) Date: Wed, 08 Sep 2004 15:31:47 -0700 Subject: [Fwd: Re: Breaking wafers?] In-Reply-To: <090820042224.14853.413F86970003DD2D00003A052200734076979D0 A02020E0400000E@comcast.net> References: <090820042224.14853.413F86970003DD2D00003A052200734076979D0A02020E0400000E@comcast.net> Message-ID: <6.0.1.1.2.20040908152608.02827580@erictonn.pobox.stanford.edu> Just to echo this, I diced my wafers 3 times in the past month and it never happened to me either. All I did was just strictly following the instruction. However, increasing the dicing distance sounds reasonable to solve this "random" problem since it doesn't hurt. -eric At 03:24 PM 9/8/2004, afflannery at comcast.net wrote: >Hi, > > > >Just for the record, we've diced about 5 wafers in the last 6 weeks >setting the diameter between 105 and 110. We've not had a problem with >breaking. > >I think the reason the blade sets down in the middle of the wafer is that >it thinks that it is the top. If you look at the pattern of dicing when >this happen, the edges of the incomplete cuts form a circle. I think it >gets confused as to its Y location relative to the wafer when you do your >alignment on a dicing lane at the edge, not in the center. I may make my >first cut at the edge, but I always align to a dicing lane in the center. > >Just my $0.02, and that's about all it is worth. > > > >Tony > > > >-------------- Original message -------------- > > > Hi everyone! > > > > Thanks for your inputs! I think Karl has provided the historical > > perspective, and explains why a larger diameter is useful. So, I'll > > change the operating procedure to reflect these inputs (with the > > recommendation to run at 150 mm, whatever the substrate size, > > recognizing that this negates the entry speed feature). By the way, > > this morning I tried using 200 mm as suggested by some, but it seems > > that the stage sometimes gets stuck because it's hit a limit switch - so > > based on this, I think 150 mm might be better (please let me know if > > your experience suggests otherwise!) > > > > Thanks again -- > > > > Mary > > > > > > -------- Original Message -------- > > Subject: Re: Breaking wafers? >! > Date: Tue, 7 Sep 2004 17:38:15 -0700 (PDT) > > From: Karl Brandt > > To: Mary Tang > > > > > > Believe it or not, this was a problem from the first day we got the tool > > from K&S. After repeated attempts by K&S to resolve it, they finally > > threw > > up their hands and said they simply had no idea what was wrong or how to > > fix it. The accepted workaround has been to set the wafer diameter to > > some > > large diameter. > > > > -Karl > > > > ********************************************************************* > > Karl Brandt > > http://people.ucsc.edu/~kbrandt/ > > > > > > On Tue, 7 Sep 2004, Mary Tang wrote: > > > > > Hi everyone -- > > > > > > "rosti" dropped by my office to say that he was thinking about using the > > > wafersaw, but was concerned about a problem he h! ad experienced a > couple > > > of times in which the saw BROKE his wafer. He says that instead of > > > starting on the edge, in these instances, the saw blade dropped onto the > > > middle of the wafer and thus broke his wafers. The last instance that > > > he observed was some time back last October or so. > > > > > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > > > expended a lot of time and energy into it -- you simply can't afford to > > > have it smashed. I'm also really concerned because I've been training > > > on the wafersaw for a couple of years now, but have not observed this > > > problem nor had I heard about it from anyone (and here I thought I knew > > > all the machine's quirks). I had heard that it used to be a problem, > > > but not seen since the system was basically rebuilt a few years ago. > > > Now, I'm hearing otherwise... > > > > > > Has anyone else had this problem? If so, coul! d you let me know > > > approximately when it happened and how often (if you were "lucky", like > > > rosti, and got hit more than once?) And maybe even the circumstances > > > when it occurred (if you remember). Your feedback will help us decide > > > what to do (if the darned thing is breaking wafers intermittently, we > > > may need to take it off-line...) > > > > > > And, most importantly, if you observe this or any other problem, please, > > > please, please report it on Coral! (I'm going back several years, and > > > don't happen to see anything about the machine breaking wafers...) > > > > > > Thanks, > > > > > > Mary > > > > > > > > > -- > > > Mary X. Tang, Ph.D. > > > Stanford Nanofabrication Facility > > > CIS Room 136, Mail Code 4070 > > > Stanford, CA 94305 > > > (650)723-9980 > > > mtang@! stanford.edu > > > http://snf.stanford.edu > > > >& > >gt; > -------------- next part -------------- An HTML attachment was scrubbed... URL: From mtang at snf.stanford.edu Wed Sep 8 15:36:23 2004 From: mtang at snf.stanford.edu (Mary Tang) Date: Wed, 08 Sep 2004 15:36:23 -0700 Subject: [Fwd: RE: Breaking wafers?] Message-ID: <413F8967.B7947F0F@snf.stanford.edu> Hi again -- And Don Arnold agrees with Tony. And Jim Kruger mentioned that his recently diced wafer likewise had concentric undiced areas... So, this will be another change to the operating procedures... Hey, I like this practice of deciding on operating procedures by consensus... Mary -------- Original Message -------- Subject: RE: Breaking wafers? Date: Tue, 7 Sep 2004 15:04:36 -0700 From: "Don W. Arnold" To: "Mary Tang" Mary, I used to have this problem. I t has been some time since I used the KS, but I believe that it has to do with where you do the alignment. I got the impression that the machine was assuming that the line on which you were doing your alignment was the center (and thus the widest part) of the wafer. In this mode, for example, if you were aligning at the near edge of the wafer, the machine would assume that your wafer was getting narrower as the cutting line was moving away from you. In fact the wafer was getting wider. When I encountered the problem, I noticed that others had been setting the machine to 200 mm diameters, but I think, in retrospect, this was going the long way around to solve the problem. As I recall, I found that if I aligned in the center of the wafers, things were OK. You would be able to quickly confirm this on a dummy wafer to see if, perhaps, things changed as a result of the rebuild. Hope this helps. Don Don Wesley Arnold Eksigent Technologies, LLC 2021 Las Positas Court, Suite 161 Livermore, CA 94550 925-960-8869 x302 - Phone 925-960-8867 - FAX dwarnold at eksigent.com -----Original Message----- From: Mary Tang [mailto:mtang at snf.stanford.edu] Sent: Tuesday, September 07, 2004 2:37 PM To: wafersaw at snf.stanford.edu Cc: rcrane; Paul Rissman; jhaydon Subject: Breaking wafers? Hi everyone -- "rosti" dropped by my office to say that he was thinking about using the wafersaw, but was concerned about a problem he had experienced a couple of times in which the saw BROKE his wafer. He says that instead of starting on the edge, in these instances, the saw blade dropped onto the middle of the wafer and thus broke his wafers. The last instance that he observed was some time back last October or so. Now I'm worried! Usually, when a wafer is ready for dicing, you've expended a lot of time and energy into it -- you simply can't afford to have it smashed. I'm also really concerned because I've been training on the wafersaw for a couple of years now, but have not observed this problem nor had I heard about it from anyone (and here I thought I knew all the machine's quirks). I had heard that it used to be a problem, but not seen since the system was basically rebuilt a few years ago. Now, I'm hearing otherwise... Has anyone else had this problem? If so, could you let me know approximately when it happened and how often (if you were "lucky", like rosti, and got hit more than once?) And maybe even the circumstances when it occurred (if you remember). Your feedback will help us decide what to do (if the darned thing is breaking wafers intermittently, we may need to take it off-line...) And, most importantly, if you observe this or any other problem, please, please, please report it on Coral! (I'm going back several years, and don't happen to see anything about the machine breaking wafers...) Thanks, Mary -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From mtang at snf.stanford.edu Wed Sep 15 07:30:11 2004 From: mtang at snf.stanford.edu (Mary Tang) Date: Wed, 15 Sep 2004 07:30:11 -0700 Subject: Reservation cancelled Message-ID: <414851F3.3CBC509F@snf.stanford.edu> Hi all -- I had a reservation for 10-12 today, but just cancelled, in case any of you could use it. Mary -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From ben.jian at arrayedfiberoptics.com Wed Sep 15 14:30:37 2004 From: ben.jian at arrayedfiberoptics.com (Ben Jian) Date: Wed, 15 Sep 2004 14:30:37 -0700 Subject: Breaking wafers? We saw it also today In-Reply-To: <413E30DE.1013DB70@snf.stanford.edu> Message-ID: <000b01c49b6b$416d8900$526418ac@laptop> Hi Mary, Today Wei was doing wafer docing and we saw the same phenomenon, for the first time ever. We were trying to dice the top-most part of a four inch wafer. The blade came down on our wafer and the blade was broken. Luckily, our wafer is OK. We suspect that this problem might have something to do with two other things. First, maybe a sensor is defective (we did see some warning message like "sensor bad" when the problem occurred but did not write it down carefully, sorry). Second, the fact that the machine does not go to the true center of the wafer stage when you hit "Align" but to the bottom part of the wafer chuck. Maybe one of these two is the source of the problem? Regards. Ben Jian -----Original Message----- From: Mary Tang [mailto:mtang at snf.stanford.edu] Sent: Tuesday, September 07, 2004 3:06 PM To: Myers, Alan M Cc: wafersaw at snf.stanford.edu; rcrane; Paul Rissman; jhaydon Subject: Re: Breaking wafers? Thanks, I'd absolutely no idea about this. I'd been told (by Len, the saw expert) that setting the diameter larger was helpful for the occasional problem in which the saw didn't cut all the way across, but maybe this is related to starting in the middle... This is easy to do in principle, but does mean we wouldn't be able to take advantage of a slow entry speed (though perhaps small insurance against breaking wafers...) I'll try it out and see if I can likewise induce/cure the problem. And unless I hear otherwise, I'll plan on adding Alan's method to the operating procedures and training... Mary "Myers, Alan M" wrote: > Mary, > I used to have this problem every time I use the saw. I > learned the secret is to set the wafer diameter 200 mm whenever I get > near the top of the wafer. It may take a little longer, but at least > the blades and the wafers remain intact. > > Alan > > -----Original Message----- > From: Mary Tang [mailto:mtang at snf.stanford.edu] > Sent: Tuesday, September 07, 2004 2:37 PM > To: wafersaw at snf.stanford.edu > Cc: rcrane; Paul Rissman; jhaydon > Subject: Breaking wafers? > > Hi everyone -- > > "rosti" dropped by my office to say that he was thinking about using > the wafersaw, but was concerned about a problem he had experienced a > couple of times in which the saw BROKE his wafer. He says that > instead of starting on the edge, in these instances, the saw blade > dropped onto the middle of the wafer and thus broke his wafers. The > last instance that he observed was some time back last October or so. > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > expended a lot of time and energy into it -- you simply can't afford > to have it smashed. I'm also really concerned because I've been > training on the wafersaw for a couple of years now, but have not > observed this problem nor had I heard about it from anyone (and here I > thought I knew all the machine's quirks). I had heard that it used to > be a problem, but not seen since the system was basically rebuilt a > few years ago. Now, I'm hearing otherwise... > > Has anyone else had this problem? If so, could you let me know > approximately when it happened and how often (if you were "lucky", > like rosti, and got hit more than once?) And maybe even the > circumstances when it occurred (if you remember). Your feedback will > help us decide what to do (if the darned thing is breaking wafers > intermittently, we may need to take it off-line...) > > And, most importantly, if you observe this or any other problem, > please, please, please report it on Coral! (I'm going back several > years, and don't happen to see anything about the machine breaking > wafers...) > > Thanks, > > Mary > > -- > Mary X. Tang, Ph.D. > Stanford Nanofabrication Facility > CIS Room 136, Mail Code 4070 > Stanford, CA 94305 > (650)723-9980 > mtang at stanford.edu > http://snf.stanford.edu -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From eap at gloworm.Stanford.EDU Wed Sep 15 15:20:39 2004 From: eap at gloworm.Stanford.EDU (Eric Perozziello) Date: Wed, 15 Sep 2004 15:20:39 -0700 (PDT) Subject: Breaking wafers? We saw it also today In-Reply-To: <000b01c49b6b$416d8900$526418ac@laptop> Message-ID: It goes to the last place aligned, so if you re-align at the center, it will start going to the center. -Eric On Wed, 15 Sep 2004, Ben Jian wrote: > Hi Mary, > > Today Wei was doing wafer docing and we saw the same phenomenon, for the > first time ever. We were trying to dice the top-most part of a four inch > wafer. The blade came down on our wafer and the blade was broken. > Luckily, our wafer is OK. > > We suspect that this problem might have something to do with two other > things. First, maybe a sensor is defective (we did see some warning > message like "sensor bad" when the problem occurred but did not write it > down carefully, sorry). Second, the fact that the machine does not go to > the true center of the wafer stage when you hit "Align" but to the > bottom part of the wafer chuck. Maybe one of these two is the source of > the problem? > > Regards. > > Ben Jian > > -----Original Message----- > From: Mary Tang [mailto:mtang at snf.stanford.edu] > Sent: Tuesday, September 07, 2004 3:06 PM > To: Myers, Alan M > Cc: wafersaw at snf.stanford.edu; rcrane; Paul Rissman; jhaydon > Subject: Re: Breaking wafers? > > > Thanks, > > I'd absolutely no idea about this. I'd been told (by Len, the saw > expert) that setting the diameter larger was helpful for the occasional > problem in which the saw didn't cut all the way across, but maybe this > is related to starting in the middle... This is easy to do in > principle, but does mean we wouldn't be able to take advantage of a slow > entry speed (though perhaps small insurance against breaking wafers...) > > I'll try it out and see if I can likewise induce/cure the problem. > > And unless I hear otherwise, I'll plan on adding Alan's method to the > operating procedures and training... > > Mary > > "Myers, Alan M" wrote: > > > Mary, > > I used to have this problem every time I use the saw. I > > learned the secret is to set the wafer diameter 200 mm whenever I get > > near the top of the wafer. It may take a little longer, but at least > > the blades and the wafers remain intact. > > > > Alan > > > > -----Original Message----- > > From: Mary Tang [mailto:mtang at snf.stanford.edu] > > Sent: Tuesday, September 07, 2004 2:37 PM > > To: wafersaw at snf.stanford.edu > > Cc: rcrane; Paul Rissman; jhaydon > > Subject: Breaking wafers? > > > > Hi everyone -- > > > > "rosti" dropped by my office to say that he was thinking about using > > the wafersaw, but was concerned about a problem he had experienced a > > couple of times in which the saw BROKE his wafer. He says that > > instead of starting on the edge, in these instances, the saw blade > > dropped onto the middle of the wafer and thus broke his wafers. The > > last instance that he observed was some time back last October or so. > > > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > > expended a lot of time and energy into it -- you simply can't afford > > to have it smashed. I'm also really concerned because I've been > > training on the wafersaw for a couple of years now, but have not > > observed this problem nor had I heard about it from anyone (and here I > > > thought I knew all the machine's quirks). I had heard that it used to > > > be a problem, but not seen since the system was basically rebuilt a > > few years ago. Now, I'm hearing otherwise... > > > > Has anyone else had this problem? If so, could you let me know > > approximately when it happened and how often (if you were "lucky", > > like rosti, and got hit more than once?) And maybe even the > > circumstances when it occurred (if you remember). Your feedback will > > help us decide what to do (if the darned thing is breaking wafers > > intermittently, we may need to take it off-line...) > > > > And, most importantly, if you observe this or any other problem, > > please, please, please report it on Coral! (I'm going back several > > years, and don't happen to see anything about the machine breaking > > wafers...) > > > > Thanks, > > > > Mary > > > > -- > > Mary X. Tang, Ph.D. > > Stanford Nanofabrication Facility > > CIS Room 136, Mail Code 4070 > > Stanford, CA 94305 > > (650)723-9980 > > mtang at stanford.edu > > http://snf.stanford.edu > > -- > Mary X. Tang, Ph.D. > Stanford Nanofabrication Facility > CIS Room 136, Mail Code 4070 > Stanford, CA 94305 > (650)723-9980 > mtang at stanford.edu > http://snf.stanford.edu > > > > From ben.jian at arrayedfiberoptics.com Wed Sep 15 16:46:03 2004 From: ben.jian at arrayedfiberoptics.com (Ben Jian) Date: Wed, 15 Sep 2004 16:46:03 -0700 Subject: Breaking wafers? Again. In-Reply-To: <413E30DE.1013DB70@snf.stanford.edu> Message-ID: <000401c49b7e$2b56f440$5c6418ac@laptop> Hi Mary, We got really "lucky" that the problem hit twice and two of our blades got broken. This second one happened near the center of our wafer. So the problem does not seem to be that rare. So we aborted our dicing run. Regards. Ben Jian -----Original Message----- From: Mary Tang [mailto:mtang at snf.stanford.edu] Sent: Tuesday, September 07, 2004 3:06 PM To: Myers, Alan M Cc: wafersaw at snf.stanford.edu; rcrane; Paul Rissman; jhaydon Subject: Re: Breaking wafers? Thanks, I'd absolutely no idea about this. I'd been told (by Len, the saw expert) that setting the diameter larger was helpful for the occasional problem in which the saw didn't cut all the way across, but maybe this is related to starting in the middle... This is easy to do in principle, but does mean we wouldn't be able to take advantage of a slow entry speed (though perhaps small insurance against breaking wafers...) I'll try it out and see if I can likewise induce/cure the problem. And unless I hear otherwise, I'll plan on adding Alan's method to the operating procedures and training... Mary "Myers, Alan M" wrote: > Mary, > I used to have this problem every time I use the saw. I > learned the secret is to set the wafer diameter 200 mm whenever I get > near the top of the wafer. It may take a little longer, but at least > the blades and the wafers remain intact. > > Alan > > -----Original Message----- > From: Mary Tang [mailto:mtang at snf.stanford.edu] > Sent: Tuesday, September 07, 2004 2:37 PM > To: wafersaw at snf.stanford.edu > Cc: rcrane; Paul Rissman; jhaydon > Subject: Breaking wafers? > > Hi everyone -- > > "rosti" dropped by my office to say that he was thinking about using > the wafersaw, but was concerned about a problem he had experienced a > couple of times in which the saw BROKE his wafer. He says that > instead of starting on the edge, in these instances, the saw blade > dropped onto the middle of the wafer and thus broke his wafers. The > last instance that he observed was some time back last October or so. > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > expended a lot of time and energy into it -- you simply can't afford > to have it smashed. I'm also really concerned because I've been > training on the wafersaw for a couple of years now, but have not > observed this problem nor had I heard about it from anyone (and here I > thought I knew all the machine's quirks). I had heard that it used to > be a problem, but not seen since the system was basically rebuilt a > few years ago. Now, I'm hearing otherwise... > > Has anyone else had this problem? If so, could you let me know > approximately when it happened and how often (if you were "lucky", > like rosti, and got hit more than once?) And maybe even the > circumstances when it occurred (if you remember). Your feedback will > help us decide what to do (if the darned thing is breaking wafers > intermittently, we may need to take it off-line...) > > And, most importantly, if you observe this or any other problem, > please, please, please report it on Coral! (I'm going back several > years, and don't happen to see anything about the machine breaking > wafers...) > > Thanks, > > Mary > > -- > Mary X. Tang, Ph.D. > Stanford Nanofabrication Facility > CIS Room 136, Mail Code 4070 > Stanford, CA 94305 > (650)723-9980 > mtang at stanford.edu > http://snf.stanford.edu -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From mtang at snf.stanford.edu Thu Sep 16 07:46:06 2004 From: mtang at snf.stanford.edu (Mary Tang) Date: Thu, 16 Sep 2004 07:46:06 -0700 Subject: Breaking wafers? We saw it also today References: Message-ID: <4149A72E.7165065C@snf.stanford.edu> Hi Wei & Ben -- I'm sorry this happened... I saw another note from you later in the day, saying this happened again, is that correct? Did you do your street alignment in the center of the wafer (as opposed to the flat) according to Eric's note? I have to admit that I have not experienced this problem, but feedback from other wafersaw users suggests that he is correct. Are you using a slower entry speed? And do you have to align to the bottom of the wafer? If no to both questions, then I would suggest aligning at the middle of the wafer (Eric's suggestion) and using 200 mm as the diameter for the top 1/3 of the wafer (Alan's suggestion.) Either of these suggestions seem to work for users who have experienced this and tried. Both might give you yet more security. Jim Kruger had another suggestion: to use square dimensions instead of the round ones. So far, he has found this to work. All these suggestions make sense, because the problem appears to be in how the wafersaw computer maps out the area to be diced -- if it is a circle that is off-center (i.e., off-set in the Y-direction), then the machine thinks it has a narrower area to cut towards the top of the wafer, when it is actually positioned near the middle. I'll definitely add these suggestions to the training and will add them to the operating procedures as well. Please let me know if these procedure changes do not work for you, as then we'll need to investigate further. (I am somewhat reluctant to expend a lot of time investigating now, because I understand now that this was a problem from the beginning, when the machine was installed, but that K&S and the SNF staff at the time gave up on it because they could not find the cause and the computer was no longer supported by K&S -- and because specifying a 150 mm or larger substrate eliminated the problem. We could consider upgrading the computer -- I understand from Len, who looked into this, that this requires a substantial rebuilding of the system and runs about $60K.) Again, please let me know if any of these suggestions works for you. Thanks, Mary Eric Perozziello wrote: > It goes to the last place aligned, so if you re-align at the center, > it will start going to the center. > > -Eric > > On Wed, 15 Sep 2004, Ben Jian wrote: > > > Hi Mary, > > > > Today Wei was doing wafer docing and we saw the same phenomenon, for the > > first time ever. We were trying to dice the top-most part of a four inch > > wafer. The blade came down on our wafer and the blade was broken. > > Luckily, our wafer is OK. > > > > We suspect that this problem might have something to do with two other > > things. First, maybe a sensor is defective (we did see some warning > > message like "sensor bad" when the problem occurred but did not write it > > down carefully, sorry). Second, the fact that the machine does not go to > > the true center of the wafer stage when you hit "Align" but to the > > bottom part of the wafer chuck. Maybe one of these two is the source of > > the problem? > > > > Regards. > > > > Ben Jian > > > > -----Original Message----- > > From: Mary Tang [mailto:mtang at snf.stanford.edu] > > Sent: Tuesday, September 07, 2004 3:06 PM > > To: Myers, Alan M > > Cc: wafersaw at snf.stanford.edu; rcrane; Paul Rissman; jhaydon > > Subject: Re: Breaking wafers? > > > > > > Thanks, > > > > I'd absolutely no idea about this. I'd been told (by Len, the saw > > expert) that setting the diameter larger was helpful for the occasional > > problem in which the saw didn't cut all the way across, but maybe this > > is related to starting in the middle... This is easy to do in > > principle, but does mean we wouldn't be able to take advantage of a slow > > entry speed (though perhaps small insurance against breaking wafers...) > > > > I'll try it out and see if I can likewise induce/cure the problem. > > > > And unless I hear otherwise, I'll plan on adding Alan's method to the > > operating procedures and training... > > > > Mary > > > > "Myers, Alan M" wrote: > > > > > Mary, > > > I used to have this problem every time I use the saw. I > > > learned the secret is to set the wafer diameter 200 mm whenever I get > > > near the top of the wafer. It may take a little longer, but at least > > > the blades and the wafers remain intact. > > > > > > Alan > > > > > > -----Original Message----- > > > From: Mary Tang [mailto:mtang at snf.stanford.edu] > > > Sent: Tuesday, September 07, 2004 2:37 PM > > > To: wafersaw at snf.stanford.edu > > > Cc: rcrane; Paul Rissman; jhaydon > > > Subject: Breaking wafers? > > > > > > Hi everyone -- > > > > > > "rosti" dropped by my office to say that he was thinking about using > > > the wafersaw, but was concerned about a problem he had experienced a > > > couple of times in which the saw BROKE his wafer. He says that > > > instead of starting on the edge, in these instances, the saw blade > > > dropped onto the middle of the wafer and thus broke his wafers. The > > > last instance that he observed was some time back last October or so. > > > > > > Now I'm worried! Usually, when a wafer is ready for dicing, you've > > > expended a lot of time and energy into it -- you simply can't afford > > > to have it smashed. I'm also really concerned because I've been > > > training on the wafersaw for a couple of years now, but have not > > > observed this problem nor had I heard about it from anyone (and here I > > > > > thought I knew all the machine's quirks). I had heard that it used to > > > > > be a problem, but not seen since the system was basically rebuilt a > > > few years ago. Now, I'm hearing otherwise... > > > > > > Has anyone else had this problem? If so, could you let me know > > > approximately when it happened and how often (if you were "lucky", > > > like rosti, and got hit more than once?) And maybe even the > > > circumstances when it occurred (if you remember). Your feedback will > > > help us decide what to do (if the darned thing is breaking wafers > > > intermittently, we may need to take it off-line...) > > > > > > And, most importantly, if you observe this or any other problem, > > > please, please, please report it on Coral! (I'm going back several > > > years, and don't happen to see anything about the machine breaking > > > wafers...) > > > > > > Thanks, > > > > > > Mary > > > > > > -- > > > Mary X. Tang, Ph.D. > > > Stanford Nanofabrication Facility > > > CIS Room 136, Mail Code 4070 > > > Stanford, CA 94305 > > > (650)723-9980 > > > mtang at stanford.edu > > > http://snf.stanford.edu > > > > -- > > Mary X. Tang, Ph.D. > > Stanford Nanofabrication Facility > > CIS Room 136, Mail Code 4070 > > Stanford, CA 94305 > > (650)723-9980 > > mtang at stanford.edu > > http://snf.stanford.edu > > > > > > > > -- Mary X. Tang, Ph.D. Stanford Nanofabrication Facility CIS Room 136, Mail Code 4070 Stanford, CA 94305 (650)723-9980 mtang at stanford.edu http://snf.stanford.edu From jimkruger at yahoo.com Mon Sep 27 16:13:00 2004 From: jimkruger at yahoo.com (jim kruger) Date: Mon, 27 Sep 2004 16:13:00 -0700 (PDT) Subject: wafersaw free and X-Y vs Dia Message-ID: <20040927231300.40030.qmail@web40913.mail.yahoo.com> Finished early, in part due to using X-Y instead of 150 mm Dia. I set 110 mm for both X and Y for 100 mm wafers (Dia is automatically disabled). I see no advantage to using "Dia" if it must be set to 150 mm to avoid "short cuts" (I found even that did not work reliably). ontact me if you have questions. jimkruger __________________________________ Do you Yahoo!? New and Improved Yahoo! Mail - Send 10MB messages! http://promotions.yahoo.com/new_mail