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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Hi Bob,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Arcing would be mitigated with a charge dissipation layer, like AquaSave, Electra92, thin film of sacrificial aluminum, or equivalent.<br>
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However, I’d like to propose an alternative hypothesis for consideration, given the information provided. The evaporation process is heating the resist (PMMA/co-MMA stack?), facilitating crack formation where stress is concentrated between the two sharp points.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Incomplete arcs don’t form, as in the case of your metal lines extending from the two sides of the 8 um gap, so give the cracking hypothesis some consideration. Resist cracking
is much more common!<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Travis Massey<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Staff Scientist, LLNL<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> labnetwork <labnetwork-bounces@mtl.mit.edu>
<b>On Behalf Of </b>Geil, Bob<br>
<b>Sent:</b> Tuesday, May 21, 2024 1:49 PM<br>
<b>To:</b> labnetwork@mtl.mit.edu<br>
<b>Subject:</b> [labnetwork] Ebeam evaporation - arcing between features<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">Hello labnetwork,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"> I have a user that is fabricating some electrodes and has observed what appears to be arcing between the sharp points of the electrodes. Imagine features like this: > < where the distance between them is 2um
- 8um. The substrate is quartz. Fabrication approach is 1) ebeam lithography 2) ebeam evaporation and 3) lift-off.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">After EBL development, the electrode circuit is open, as intended<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">After evaporation +lift-off, there is a line about few 100nms wide that is shorting the electrodes: >-<<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">There is not a short between the electrodes with the 8um gap, however, there are some metal lines extending from the two sides: >- -<<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">All of this suggests that arcing is occurring. Has anyone observed this before and can you suggest ways to get around it?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">Thanks,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black"> Bob<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Bob Geil, PhD <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Technical Director • CHANL</span><span style="font-family:"Arial",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Dept. of Chemistry • UNC-CH<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Chapel Hill, NC <o:p></o:p></span></p>
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