<div dir="ltr">Hi,<div><div>What materials is the user trying to deposit?<br></div><div>There is definitely charging happening during ebeam evaporation (my symptoms were bubbles in PMMA resist). <br></div><div>I would recommend switching to thermal evaporation if possible, or lowering the power/rate during the deposition. It could also be caused by contamination in the crucible. </div><div>Using magnets around the substrate to deflect electrons from reaching the substrate also showed good results on a small area samples.</div><div><br></div><div>Thank you,</div><div>Youry</div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, May 21, 2024 at 6:44 PM Geil, Bob <<a href="mailto:bob.geil@unc.edu">bob.geil@unc.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="msg-6749967824614591756">




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Hello labnetwork,</div>
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 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.</div>
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After EBL development, the electrode circuit is open, as intended</div>
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After evaporation +lift-off, there is a line about few 100nms wide that is shorting the electrodes: >-<</div>
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There is not a short between the electrodes with the 8um gap, however, there are some metal lines extending from the two sides:  >-  -<</div>
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All of this suggests that arcing is occurring.  Has anyone observed this before and can you suggest ways to get around it?</div>
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Thanks,</div>
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  Bob</div>
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Bob Geil, PhD </div>
<div style="margin:0px;font-family:Arial,sans-serif;color:rgb(0,0,0)"><span style="font-size:10pt">Technical Director
</span><span style="font-size:13px">•</span><span style="font-size:10pt"> CHANL</span></div>
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Dept. of Chemistry • UNC-CH</div>
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Chapel Hill, NC  </div>
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