From shott at snf.stanford.edu Wed Aug 9 15:13:33 2000 From: shott at snf.stanford.edu (John Shott) Date: Wed, 09 Aug 2000 15:13:33 -0700 Subject: Testing mailing list ... Message-ID: <3991D78D.E07A558B@snf.stanford.edu> Please ignore this message ... we are debugging a problem with this mailing list. Thanks, John From flannery at leland.Stanford.EDU Fri Aug 18 08:26:38 2000 From: flannery at leland.Stanford.EDU (Anthony Flannery) Date: Fri, 18 Aug 2000 08:26:38 -0700 Subject: Pump Down Message-ID: <399D55AE.CE5C3BF0@leland.stanford.edu> Hey Gang, This morning I found that the last user had left the rough pump valve cranked all the way open. This is a big no-no. Without LN2 in the trap, there is a VERY good chance we will get major backstreaming of oil into the chamber. The last time this happened the system went down for 9 months. Refill the trap, rough pump it down (yes, you have to wait), close the rough pump valve. Thanks, Tony From jac17 at stanford.edu Fri Aug 25 12:34:22 2000 From: jac17 at stanford.edu (john chiaverini) Date: Fri, 25 Aug 2000 12:34:22 -0700 (PDT) Subject: sputtered film thickness? Message-ID: metallica users, i was wondering what thicknesses it is possible to sputter to in metallica. i'm hoping to do Cu, but i need a rather thick film. any info would be appreciated. thanks... _ _ (_)__ / / ___ john chiaverini jac17 at leland.stanford.edu / / _ \/ _ \/ _ \ __/ /\___/_//_/_//_/ america is a vast conspiracy to make you happy. |___/ --john updike From flannery at leland.Stanford.EDU Fri Aug 25 16:05:05 2000 From: flannery at leland.Stanford.EDU (Anthony Flannery) Date: Fri, 25 Aug 2000 16:05:05 -0700 Subject: sputtered film thickness? References: Message-ID: <39A6FBA1.B97139DA@leland.stanford.edu> Hi, You are limited by stress, and ultimately by the size of the target. Stress can be affected somewhat by changing the pressure. The lowest you can sputter at is somewhere around 3.5 mTorr. As you go higher, you incorporate more gas in the film. At some point it becomes more like swiss cheese and it will wipe off the wafer. You can safetly sputter up to around 6 mTorr. Above that check the film. General rule is that lower pressure -> more compressive but that's not univeral at all. Stress can also be affected by power settings. Every metal is different. You'll have to do some tests to determine the settings for a reasonable dep rate and a low stress film. Too low and no dep rate, too high and you can melt the target (and gun) so you want to stay reasonable. Temperature can work against you because of thermal expansion mismatches. I always intened to do a study and find out just how hot wafers got during sputtering, but never did. You may have to turn the power off in the middle of a long sputter to let the wafer cool, and then resume. The ultimate depth depends how the target wears. THis is different for every metal. Be VERY VERY VERY careful that you do not blast through the target and start etching the gun. You contaminate the machine with thermal paste and the company that made the guns no longer exists. Then people won't like you and won't invite you to parties. Based on my work with other metals, the best guess for an ultimate thickness of CU with one wafer, provided stress is not an issue and you pulse the deposition is somewhere around 15 um. Hope this helps. Good luck. Tony john chiaverini wrote: > > metallica users, > > i was wondering what thicknesses it is possible to sputter to in > metallica. i'm hoping to do Cu, but i need a rather thick film. any info > would be appreciated. > > thanks... > > _ _ > (_)__ / / ___ john chiaverini jac17 at leland.stanford.edu > / / _ \/ _ \/ _ \ > __/ /\___/_//_/_//_/ america is a vast conspiracy to make you happy. > |___/ --john updike From king at snf.stanford.edu Mon Aug 28 09:11:06 2000 From: king at snf.stanford.edu (Robin King) Date: Mon, 28 Aug 2000 09:11:06 -0700 (PDT) Subject: sputtered film thickness? In-Reply-To: Message-ID: John, For thick Cu films, first deposit a thin seed layer and then electroplate the rest. The sputter rate is very slow in Metallica- too slow to deposit the thickness you need. Robin King On Fri, 25 Aug 2000, john chiaverini wrote: > > metallica users, > > i was wondering what thicknesses it is possible to sputter to in > metallica. i'm hoping to do Cu, but i need a rather thick film. any info > would be appreciated. > > thanks... > > > _ _ > (_)__ / / ___ john chiaverini jac17 at leland.stanford.edu > / / _ \/ _ \/ _ \ > __/ /\___/_//_/_//_/ america is a vast conspiracy to make you happy. > |___/ --john updike > >