<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">Hello,<div>I think of “Reverse side exposure Lift-Off”, as:</div><div><br></div><div>1. Coat thick Negative photoresist on FrontSide of the mask.</div><div>2. Expose it from the BackSide of the mask and develop it.</div><div>3. Deposit the thin Gold on the FrontSide.</div><div>4. Lift-Off.</div><div><br></div><div>It might work depending on the layout: Cr features/spaces as the</div><div>UV light diffraction from the BackSide of the mask might affect it.</div><div>Success!</div><div>Bernard</div><div><br><div id="AppleMailSignature">Sent from my iPad</div><div><br>On May 30, 2019, at 4:23 PM, Jim Carroll <<a href="mailto:jim@photomaskportal.com">jim@photomaskportal.com</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr"><div class="gmail_default" style="font-family:verdana,sans-serif;color:#000000">Dear LabNetwork colleagues,</div><div class="gmail_default" style="font-family:verdana,sans-serif;color:#000000"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif;color:#000000">We are trying to add a thin film of gold over patterned chrome on a standard photomask using e-beam evaporation. We want the gold to preferentially adhere to the chrome while lifting off the glass.<br></div><div class="gmail_default" style="font-family:verdana,sans-serif;color:#000000"><br>After a few tests, it appears that the gold sticks equally well to both the glass and chrome. Ultrasonic agitation and swabbing do not selectively remove the gold from the glass while leaving it on the chrome. Eventually, after enough pressure is applied with a swab, the gold releases from both the glass and chrome. </div><div class="gmail_default" style="font-family:verdana,sans-serif;color:#000000"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif;color:#000000">Does anyone have a suggested approach?<br> <br></div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div><font size="2" face="verdana, sans-serif"><font color="#000000">Thanks,</font></font></div><div><font size="2" face="verdana, sans-serif"><font color="#000000">Jim Carroll<br></font><b style="color:rgb(0,0,0)">PhotomaskPORTAL</b><font color="#000000"><br></font></font></div><div><font color="#000000"><font size="2" face="verdana, sans-serif"><i>We help you make masks</i><br><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice"><span title="Call with Google Voice">(415) 448-6275</span></span></span></span></span></span></span></span></span></span></span></span></font></font></div><div></div></div><div><ul style="margin:0px;padding:0px 0px 8px;border:0px;outline:0px;font-size:11.818181991577148px;font-family:Helvetica,Arial,sans-serif;vertical-align:baseline;list-style:none;line-height:16.988636016845703px;display:table-cell;width:502.7272644042969px"><li style="margin:0px;padding:8px 12px 2px 0px;border:0px;outline:0px;font-style:inherit;font-size:11px;font-family:inherit;vertical-align:baseline;font-variant:inherit;line-height:1.2em"><dl style="margin:0px;padding:0px;border:0px;outline:0px;font-style:inherit;font-size:10.909090995788574px;font-family:inherit;vertical-align:baseline;font-variant:inherit;line-height:inherit;word-wrap:break-word"><a href="http://www.photomaskportal.com" target="_blank"><dl style="margin:0px;padding:0px;border:0px;outline:0px;font-style:inherit;font-size:10.909090995788574px;font-family:inherit;vertical-align:baseline;font-variant:inherit;line-height:inherit;word-wrap:break-word"><img src="http://www.photomaskportal.com/uploads/1/1/6/1/11617247/9425470.png" width="200" height="56"><br></dl></a></dl></li></ul></div></div></div></div></div></div></div></div></div></div></div>
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