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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap:break-word;-webkit-nbsp-mode: space;line-break:after-white-space'><div class=WordSection1><p class=MsoNormal>Hi Long,<o:p></o:p></p><p class=MsoNormal>Having worked with SU-8 for many years I can state that the process guidelines provided by the company are just that - Guidelines. I always advise longer than prescribed bakes after spinning. The main objective is to drive out the carrier solvent. I have spun layers of SU8 up to 750 um thick. How thick is your film? For thick films, extended bakes and additional steps are required in order to get consistent results.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>For removing the SU8 from your photomask – soaking in developer will work. Soaking in acetone also works. I find that soaking in Remover PG works best.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best,<o:p></o:p></p><p class=MsoNormal>Tom<o:p></o:p></p><p class=MsoNormal>CNF<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> labnetwork <labnetwork-bounces@mtl.mit.edu> <b>On Behalf Of </b>Chang, Long<br><b>Sent:</b> Monday, June 10, 2024 9:52 AM<br><b>To:</b> Zhichao Wang <zhichaow@udel.edu><br><b>Cc:</b> Fab Network <labnetwork@mtl.mit.edu><br><b>Subject:</b> Re: [labnetwork] Photomask sticks to SU8<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks everyone. I got the mask mostly clean with SU8 developer. Can’t wait to try again with more baking. Anyone has tips for easy and repeatable edge bead removal? I’m thinking about using a Q-tip dipped in acetone while the wafer is spinning at 500 rpm. <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal><span style='color:black'>Long Chang<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>UH Nanofabrication Facility<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'>Houston, TX<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'><a href="mailto:lvchang@central.uh.edu">lvchang@central.uh.edu</a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p></div><div><p class=MsoNormal><br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>On Jun 10, 2024, at 8:25 AM, Zhichao Wang <<a href="mailto:zhichaow@udel.edu">zhichaow@udel.edu</a>> wrote:<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>Hi Long, <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>We use 10min@65C and 30min@95C for thick SU-8 pre-bake. One of our users leaves the pre-baked wafer on a flat surface overnight and runs the exposure the next day, it seems like the film height uniformity can be slightly improved.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Best, <o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Sat, Jun 8, 2024 at 10:46 AM Howard Northfield <<a href="mailto:Howard.Northfield@uottawa.ca">Howard.Northfield@uottawa.ca</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'>Bake it longer:<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'>(rt to 65°C@200°C/min)+(10min@65°C)+(65°C to 95°C@200°C/min)+(30min@95°C)+(95°C to rt)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'>Clean the mask as you would develop; in a bath of SU-8 developer and spray rinse, followed by IPA bath and rinse.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'>Howard Northfield<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'>Research Associate<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'>Advanced Research Complex (ARC)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Aptos",sans-serif'>University of Ottawa<o:p></o:p></span></p></div><div class=MsoNormal align=center style='text-align:center'><hr size=2 width="98%" align=center></div><div id="m_-8656343098025639131divRplyFwdMsg"><p class=MsoNormal><b>From:</b> labnetwork <<a href="mailto:labnetwork-bounces@mtl.mit.edu" target="_blank">labnetwork-bounces@mtl.mit.edu</a>> on behalf of Chang, Long <<a href="mailto:lvchang@Central.UH.EDU" target="_blank">lvchang@Central.UH.EDU</a>><br><b>Sent:</b> Friday, June 7, 2024 5:50 PM<br><b>To:</b> Fab Network <<a href="mailto:labnetwork@mtl.mit.edu" target="_blank">labnetwork@mtl.mit.edu</a>><br><b>Subject:</b> [labnetwork] Photomask sticks to SU8 <o:p></o:p></p><div><p class=MsoNormal> <o:p></o:p></p></div></div><div><div><p class=MsoNormal><b><span style='font-size:9.0pt;color:#FF4233'>Attention : courriel externe | external email</span></b><span style='font-size:9.0pt;color:#FF4233'><o:p></o:p></span></p></div><div><p class=MsoNormal>Hello, <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I just used Quartz Cr photomask for the first time with SU8 3050 and the SU8 stuck to the photomask after exposure, see photo. How can I prevent SU8 from sticking to my mask? How should I clean the mask?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks,<o:p></o:p></p><div><div><div><p class=MsoNormal>Long Chang<o:p></o:p></p></div><div><p class=MsoNormal>UH Nanofabrication Facility<o:p></o:p></p></div><div><p class=MsoNormal>Houston, TX<o:p></o:p></p></div><div><p class=MsoNormal><a href="mailto:lvchang@central.uh.edu" target="_blank">lvchang@central.uh.edu</a><o:p></o:p></p></div><div><p class=MsoNormal><Screen Shot 2024-06-07 at 4.48.32 PM.png><o:p></o:p></p></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div><p class=MsoNormal>_______________________________________________<br>labnetwork mailing list<br><a href="mailto:labnetwork@mtl.mit.edu" target="_blank">labnetwork@mtl.mit.edu</a><br><a href="https://urldefense.com/v3/__https:/mtl.mit.edu/mailman/listinfo.cgi/labnetwork__;!!LkSTlj0I!D0ZXGmsjLdP-1BtJkBRxOiAL0scuehEXAXXLqNzgnKtfepa3Q3fhKti1rRKbyOp4h3n2pWhZEN4qA2BiLKnALPA$" target="_blank">https://mtl.mit.edu/mailman/listinfo.cgi/labnetwork</a><o:p></o:p></p></div></blockquote></div><p class=MsoNormal><br clear=all><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><span class=gmailsignatureprefix>-- </span><o:p></o:p></p><div><div><div><div><div><p class=MsoNormal><span style='color:#0B5394;border:solid windowtext 1.0pt;padding:0in'><img border=0 width=96 height=95 style='width:1.0in;height:.9916in' id="Picture_x0020_2" src="cid:~WRD0000.jpg" alt="Image removed by sender."></span><o:p></o:p></p></div><div><p class=MsoNormal><b><span style='font-size:13.5pt;font-family:"Courier New";color:#0B5394'>Zhichao "Chao" Wang, Ph.D.</span></b><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>Lithography Engineer</span></i><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>UDNF</span></i><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>University of Delaware</span></i><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>Pronouns: He/Him/His</span></i><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-size:9.0pt;font-family:"Trebuchet MS",sans-serif;color:#0B5394'>------------------------</span></i><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>Office Number</span></i><i><span style='font-family:"MS Gothic";color:#0B5394'>：</span></i><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>(302) 831-4839</span></i><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>221 Academy St.</span></i><i><span style='font-family:"MS Gothic";color:#0B5394'>，</span></i><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>RM170</span></i><o:p></o:p></p></div><div><p class=MsoNormal><i><span style='font-family:"Trebuchet MS",sans-serif;color:#0B5394'>Newark, DE 19711</span></i><o:p></o:p></p></div></div></div></div></div></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>