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--></style></head><body lang="EN-US" link="#467886" vlink="#96607D" style="word-wrap:break-word"><div class="WordSection1"><p class="MsoNormal">Hi Russ,</p><p class="MsoNormal"> </p><p class="MsoNormal">You should be fine putting PCBs into an ebeam. I think for a basic PCB the max heat is around 120C. A few nanometers of gold won’t get the substrate holder anywhere near that hot. I regularly heat them to 100C when attaching wells to my own chips which again the holder won’t even approach in temperature. </p><p class="MsoNormal"> </p><p class="MsoNormal">This may not be necessary, though. I’d be worried that depositing gold would short a lot of the contact pads unless you meticulously mask them, which would be a pain. I usually give my PCBs a few minutes soak in IPA and rinse with DI before mounting and wirebonding and this seems to improve wirebonding significantly. I use an aluminum wedge bonder. I order them from <a href="https://jlcpcb.com/">JLCPCB</a> and I make sure the surface finish is Electroless Nickel Immersion Gold (“ENIG”) to allow for wirebonding.</p><p class="MsoNormal"> </p><p class="MsoNormal">Best,</p><p class="MsoNormal">Mike</p><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><p class="MsoNormal"><span style="color:black">___</span></p><p class="MsoNormal"><span style="color:black">Michael Geiwitz, PhD</span></p><p class="MsoNormal"><span style="color:black">Boston College Cleanroom and Nanofabrication Facility</span></p><p class="MsoNormal"><span style="color:black">Cleanroom Director/Physics Teaching Faculty</span></p><p class="MsoNormal"><span style="color:black">245 Beacon, #005</span></p><p class="MsoNormal"><span style="color:black">CR: (617) 552-0049</span></p><p class="MsoNormal"><span style="color:black">Cell: (845) 514-0708</span></p><p class="MsoNormal"><span style="color:black"><a href="mailto:geiwitz@bc.edu"><span style="color:#4285f4;border:none windowtext 1.0pt;padding:0in">geiwitz@bc.edu</span></a></span></p><p class="MsoNormal"><span style="mso-ligatures:standardcontextual"> </span></p></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div><p class="MsoNormal"> </p><div><div style="border:none;border-top:solid #e1e1e1 1.0pt;padding:3.0pt 0in 0in 0in"><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 <<a href="mailto:labnetwork-bounces@mtl.mit.edu">labnetwork-bounces@mtl.mit.edu</a>> <b>On Behalf Of </b>Russ Renzas<br><b>Sent:</b> Wednesday, July 1, 2026 10:11 PM<br><b>To:</b> Network Fab <<a href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a>><br><b>Cc:</b> Lihua Xiao <<a href="mailto:lxiao@unr.edu">lxiao@unr.edu</a>><br><b>Subject:</b> [labnetwork] PCB in e-beam evaporator?</span></p></div></div><p class="MsoNormal"> </p><p class="MsoNormal"><span style="color:black">For a summer lab class we're trying to have students make a chip and wirebond it to a PCB. We're having trouble wirebonding to the immersion gold pads though.</span></p><p class="MsoNormal"><span style="color:black"> </span></p><p class="MsoNormal"><span style="color:black">Is it okay to put pcbs in our ebeam evaporator to evaporate Au? </span></p><p class="MsoNormal"><span style="color:black"> </span></p><p class="MsoNormal"><span style="color:black">We tried a small piece in a Au SEM prep sputter coater and that worked but it's too small for the class PCBs.</span></p><div id="ms-outlook-mobile-body-separator-line"><p class="MsoNormal"> </p><p class="MsoNormal">Thanks, also appreciate any tips on how to spec pcb metalization for wirebonding compatibility. We have both Al ultrasonic wedge and Au ball bond capabilities.</p><p class="MsoNormal"> </p></div><div id="ms-outlook-mobile-signature"><p class="MsoNormal"><span style="color:black">Russ Renzas</span></p><p class="MsoNormal"><span style="color:black">University of Nevada, Reno</span></p></div></div></body></html>