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Can you clarify a bit - are you depositing ON CdTe/CZT. or you're depositing THE CdTe/CZT? Two totally different situations<br>
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I did work with CdTe in the past , and now do some with CZT - not processing, though - and always thought that they should not be heated, but at room temperature are not an issue - well, not more than GaAs. Crumbs and shavings are bad, bulk crystal is inert.<br>
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If my memory serves me right, thermal budget for CdTe is pretty low, to the point regular photoresist process may be an issue. Hence evaporation may also be too much thermal load as well, especially if high temperature stuff like Pt is involved (and it is
a common contact for CZT) - but that should be primarily for the sample condition and researchers wouldn't want to push things that way. Check substrate temperature on a blank first... If that is all done, chamber and pump should be just fine. If you are concerned
about pieces and dust... do you have any GaAs in the facility?<br>
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On a separate note, I generate ample amounts of arsenic waste - and was told it goes "to a secure landfill" or "forever storage facility", whatever that means. I suspect CdTe waste should be the same.<br>
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mike</div>
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_______________________________________________</div>
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<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">Michael Yakimov</span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">Research scientist</span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">Department of Nanoscale Science and Engineering</span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">University at Albany - State University of NY</span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;"> </span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">253 Fuller rd.</span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">Albany NY 12203</span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;"> </span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">Phone: 518-437-8609 lab</span></p>
<p style="margin: 0px; font-family: Calibri, sans-serif; font-size: 11pt;"><span style="color: black;">e-mail: myakimov@albany.edu</span></p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> labnetwork <labnetwork-bounces@mtl.mit.edu> on behalf of Kathy Anderson <kathy.anderson@utah.edu><br>
<b>Sent:</b> Wednesday, November 13, 2024 2:49 PM<br>
<b>To:</b> labnetwork@mtl.mit.edu <labnetwork@mtl.mit.edu><br>
<b>Subject:</b> [labnetwork] CdTe Safety</font>
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<p class="x_MsoNormal">Hello Lab Network,</p>
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<p class="x_MsoNormal">Will you share with us at the University of Utah your experience analyzing the occupational hazard of processing CdTe in your research lab?</p>
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<p class="x_MsoNormal">We acknowledge the sublimation energy for CdTe is low, and the Cd escapes more readily leaving a Te rich surface. At the same time, quantifying the health and operation risks associated with e-beam and sputter processing is proving a
challenge as we communicate with our community of researchers what is and is not allowed in our toolset and why.
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<ul type="disc" style="margin-top:0in">
<li class="x_MsoListParagraph" style="margin-left:0in">Are you depositing films onto CdTe substrates using e-beam evaporation? If not, why?</li><li class="x_MsoListParagraph" style="margin-left:0in">Are you depositing films onto CdTe substrates using sputter? If not, why?</li><li class="x_MsoListParagraph" style="margin-left:0in">What is your lab’s procedure for maintaining a safe breathing space during e-beam and sputter chamber maintenance?
</li><li class="x_MsoListParagraph" style="margin-left:0in">How do you dispose of CdTe contaminated solids waste?</li><li class="x_MsoListParagraph" style="margin-left:0in">How do you dispose of deposition equipment pumps that may be contaminated with CdTe as they fail?</li><li class="x_MsoListParagraph" style="margin-left:0in">What is your lab’s CdTe substrate surface preparation process before e-beam or sputter?</li><li class="x_MsoListParagraph" style="margin-left:0in">Do you have equipment dedicated to CdTe processing as well as separate equipment where CdTe substrates are prohibited? If your deposition equipment is not separated between CdTe vs non CdTe, what limitations
do you set on those processes to ensure cross-contamination of Cadmium or CdTe is negligible from run to run?</li></ul>
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<p class="x_MsoNormal">Regards,</p>
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<p class="x_MsoNormal">Kathy Anderson</p>
<p class="x_MsoNormal">Cleanroom Process Engineer and Safety Officer</p>
<p class="x_MsoNormal">801-213-6555</p>
<p class="x_MsoNormal">801-440-1465</p>
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