<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:p="urn:schemas-microsoft-com:office:powerpoint" xmlns:a="urn:schemas-microsoft-com:office:access" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:s="uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882" xmlns:rs="urn:schemas-microsoft-com:rowset" xmlns:z="#RowsetSchema" xmlns:b="urn:schemas-microsoft-com:office:publisher" xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet" xmlns:c="urn:schemas-microsoft-com:office:component:spreadsheet" xmlns:odc="urn:schemas-microsoft-com:office:odc" xmlns:oa="urn:schemas-microsoft-com:office:activation" xmlns:html="http://www.w3.org/TR/REC-html40" xmlns:q="http://schemas.xmlsoap.org/soap/envelope/" xmlns:rtc="http://microsoft.com/officenet/conferencing" xmlns:D="DAV:" xmlns:Repl="http://schemas.microsoft.com/repl/" xmlns:mt="http://schemas.microsoft.com/sharepoint/soap/meetings/" xmlns:x2="http://schemas.microsoft.com/office/excel/2003/xml" xmlns:ppda="http://www.passport.com/NameSpace.xsd" xmlns:ois="http://schemas.microsoft.com/sharepoint/soap/ois/" xmlns:dir="http://schemas.microsoft.com/sharepoint/soap/directory/" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" xmlns:dsp="http://schemas.microsoft.com/sharepoint/dsp" xmlns:udc="http://schemas.microsoft.com/data/udc" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sub="http://schemas.microsoft.com/sharepoint/soap/2002/1/alerts/" xmlns:ec="http://www.w3.org/2001/04/xmlenc#" xmlns:sp="http://schemas.microsoft.com/sharepoint/" xmlns:sps="http://schemas.microsoft.com/sharepoint/soap/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:udcs="http://schemas.microsoft.com/data/udc/soap" xmlns:udcxf="http://schemas.microsoft.com/data/udc/xmlfile" xmlns:udcp2p="http://schemas.microsoft.com/data/udc/parttopart" xmlns:wf="http://schemas.microsoft.com/sharepoint/soap/workflow/" xmlns:dsss="http://schemas.microsoft.com/office/2006/digsig-setup" xmlns:dssi="http://schemas.microsoft.com/office/2006/digsig" xmlns:mdssi="http://schemas.openxmlformats.org/package/2006/digital-signature" xmlns:mver="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns:mrels="http://schemas.openxmlformats.org/package/2006/relationships" xmlns:spwp="http://microsoft.com/sharepoint/webpartpages" xmlns:ex12t="http://schemas.microsoft.com/exchange/services/2006/types" xmlns:ex12m="http://schemas.microsoft.com/exchange/services/2006/messages" xmlns:pptsl="http://schemas.microsoft.com/sharepoint/soap/SlideLibrary/" xmlns:spsl="http://microsoft.com/webservices/SharePointPortalServer/PublishedLinksService" xmlns:Z="urn:schemas-microsoft-com:" xmlns:st="" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 12 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>HI,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>How is your base pressure and leak back rate? If you have a leak it may be adding extra O2 which the Ti just gobbles up. What machine are you doing this in?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>How is your water cooling flow, if there is reduced flow it will affect the process, stuff will heat up, the heat may cause the target to de-bond, thus creating a bad RF circuit. That recently happened to us on a sputter tool, the target de-bonded slightly and the rate dropped.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Are you doing a reactive process or do you have a TiO2 target? Is your pressure control working properly, is the gate valve actively controlled ? if so if there anything wrong with the pressure signal to the gate valve?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hope this helps.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Rick<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Rick Morrison<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Senior Member Technical Staff <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Acting Group Leader Mems Fabrication<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Draper Laboratory<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>555 Technology Square<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Cambridge, MA 02139<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>617-258-3420<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> labnetwork-bounces@mtl.mit.edu [mailto:labnetwork-bounces@mtl.mit.edu] <b>On Behalf Of </b>Steven Foland<br><b>Sent:</b> Friday, June 24, 2011 11:05 AM<br><b>To:</b> Gupta, Su<br><b>Cc:</b> labnetwork@mtl.mit.edu; Keith Bradshaw<br><b>Subject:</b> Re: [labnetwork] Sputter problem<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'>Hi Prof. Gupta,<br><br>We are doing RF sputtering, not DC. Cleaning the target longer does increase deposition rate temporarily, but it drops back down quickly. We are most likely operating at the "oxidized" rate, but still are unsure why we are experiencing this gradual decline in film thickness.<br><br>Here is my data from yesterday:<br>1st run: 5 minute clean cycle, 5 minute coat cycle: 250 Angstroms<br>2nd run: 5 min clean, 10 min coat: 198 Angstroms<br>3rd run: 10 min clean, 5 min coat: 118 Angstroms<br>4th run: 5 min clean, 5 min coat: 96 Angstroms<br>5th run: 5 min clean, 5 min coat: 80 Angstroms<br>6th run: 5 min clean, 5 min coat: 90 Angstroms<br>7th run: 20 min clean, 5 min coat: 120 Angstroms<br><br>So you see, we have a gradual decline in dep rate, but can increase the dep rate slightly by running a longer clean cycle.<br><br>If enough time has passed (a day or two) between runs, the rate increases back to its original value of ~250 Angstroms in 5 minutes.<br><br>Thoughts?<br><br>Thank you,<br>Steven Foland<o:p></o:p></p><div><p class=MsoNormal>On Thu, Jun 23, 2011 at 11:54 PM, Gupta, Su <<a href="mailto:sgupta@eng.ua.edu">sgupta@eng.ua.edu</a>> wrote:<o:p></o:p></p><p class=MsoNormal>Hi Keith:<br><br>Can you give me some more details about your sputter system and the processs? For instance, are you sputtering reactively from a Ti target or is it TiO2? If you are doing DC reactive sputtering from an elemental target, then the target voltage is the best indicator of what is going on with the process. For instance, the target may be oxidizing further with each run (even with the preclean) and you may be dropping down the slope of the hysteresis loop from the 'metallic' rate to the "oxidized" rate, which would be accurately reflected in a drop in the target voltage. A small leak or outgassing could also cause this type of problem, but it probably would not be as regular and systematic as what you are observing.<br><br>Regards,<br>Su Gupta<br>Assoc. Prof, MTE<br>Faculty Director, uamcro<br>Univ. of Alabama<br>________________________________<br>From: <a href="mailto:labnetwork-bounces@mtl.mit.edu">labnetwork-bounces@mtl.mit.edu</a> [<a href="mailto:labnetwork-bounces@mtl.mit.edu">labnetwork-bounces@mtl.mit.edu</a>] On Behalf Of Keith Bradshaw [<a href="mailto:bradshaw1234@gmail.com">bradshaw1234@gmail.com</a>]<br>Sent: Thursday, June 23, 2011 5:09 PM<br>To: <a href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a>; Steven Foland<br>Subject: [labnetwork] Sputter problem<o:p></o:p></p><div><div><p class=MsoNormal><br>We are sputtering TiO2 .<br><br>We begin the day with a 250 angstrom rate....each subsequent run is reduced by 10-15% in rate until we are at a 125 angstrom rate. We are not changing anything.<br><br>Next day we begin again at 250.<br><br>Tried argon clean between runs, tried 3 hour wait between runs, we are using a load lock and vacuum looks stable , still rate drops on each run.<br><br>Any ideas?<br><br>cordially,<br><br>Keith Bradshaw<br>Dallas<o:p></o:p></p></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></body></html>