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<div>Dear Colleagues,</div>
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<div>Sincere thanks to all of you whom have taken the time to provide so many insights and excellent suggestions – it's greatly appreciated. For the benefit of the community, an update will be provided after we try some of these suggestions and obtain additional
experimental results.</div>
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<div>Best regards,</div>
<div>Vito</div>
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<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Vito Logiudice M.A.Sc., P.Eng.<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Director of Operations, Quantum NanoFab<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">University of Waterloo<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">200 University Avenue West<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Waterloo, ON Canada N2L 3G1<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Tel: 1-519-888-4567 ext. 38703<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Email: <a href="mailto:vlogiudi@uwaterloo.ca" style="color: blue; ">vlogiudi@uwaterloo.ca</a></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Website:
<a href="https://qncfab.uwaterloo.ca">https://qncfab.uwaterloo.ca</a>/</p>
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<span style="font-weight:bold">From: </span>Vito Logiudice <<a href="mailto:vito.logiudice@uwaterloo.ca">vito.logiudice@uwaterloo.ca</a>><br>
<span style="font-weight:bold">Date: </span>Monday, 28 January, 2013 5:23 PM<br>
<span style="font-weight:bold">To: </span>"<a href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a>" <<a href="mailto:labnetwork@mtl.mit.edu">labnetwork@mtl.mit.edu</a>><br>
<span style="font-weight:bold">Subject: </span>[labnetwork] N2 pump purge source of chamber contamination?<br>
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<div>Dear Colleagues,</div>
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<div>We are depositing single crystal diamond via PECVD in a newly purchased tool dedicated to this process. Initial deposition runs have revealed the presence of film defects caused by stray nitrogen. The system and process gas lines have been helium leak-tested.
The load-locked process chamber is pumped down by a turbo pump backed by a nitrogen-purged dry pump (the process makes use of methane and hydrogen). We're wondering if the N2 purge on the roughing pump might somehow be contributing to the problem.</div>
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<div>I'd appreciate hearing the community's thoughts on the possibility of nitrogen back flow from an N2-purged roughing pump back to the process chamber.</div>
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<div>Many thanks,</div>
<div>Vito</div>
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<div>-- </div>
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<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Vito Logiudice M.A.Sc., P.Eng.<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Director of Operations, Quantum NanoFab<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">University of Waterloo<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">200 University Avenue West<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Waterloo, ON Canada N2L 3G1<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Tel: 1-519-888-4567 ext. 38703<o:p></o:p></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Email: <a href="mailto:vlogiudi@uwaterloo.ca" style="color: blue; ">vlogiudi@uwaterloo.ca</a></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0.0001pt; font-size: 11pt; ">Website:
<a href="https://qncfab.uwaterloo.ca">https://qncfab.uwaterloo.ca</a>/</p>
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