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<p class="MsoNormal">For our RCA process at Purdue/BNC, we have a small (6ft.) dedicated Kinetics RCA cleaning hood with heated below deck level baths for SC1/SC2 and a smaller unheated bath for HF. I have installed a separate cabinet for the HF and HCl adjacent
to the hood. This is marked as for RCA only to a) separate the RCA supplies from the main supply and b) to shorten the distance between the cabinet and hood.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The HF is in a smaller semi-opaque white bottle that is easy to determine the level. The HCl bottles are double the size and glass. Each has their own shelf to visually separate them as well. H2O2 goes into a small fridge on the other side
of the hood, again to separate the supply and provide quick access.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Access to this hood is restricted by requiring a 2 hour training session in which the user sets up, uses, and cleans up the process from start to finish. Prior HF procedures that are outlined originally in the cleanroom access training
are reinforced here and the nearest HF exposure kit (6ft behind the user) is pointed out.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Basically the strategy is a sort of defense-in-depth of individual mistake-proofing features. To my knowledge we haven’t had any exposure incidents stemming from this hood in the ~4 years it’s been operational.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My catchphrase when working with RCA and Piranha is as follows: “If you ever stop being scared and respectful of these chemicals, you need to stop working with them.”<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Rich Hosler<o:p></o:p></p>
<p class="MsoNormal">Research Engineer (Thermal/PECVD)<o:p></o:p></p>
<p class="MsoNormal">Purdue University – Birck Nanotechnology Center<o:p></o:p></p>
<p class="MsoNormal">hosler0@purdue.edu<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b>From:</b> labnetwork <labnetwork-bounces@mtl.mit.edu> <b>
On Behalf Of </b>Savitha P<br>
<b>Sent:</b> Wednesday, February 15, 2023 7:19 AM<br>
<b>To:</b> labnetwork@mtl.mit.edu<br>
<b>Subject:</b> Re: [labnetwork] HF storage<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana",sans-serif;color:black">----
<b>External Email</b>: Use caution with attachments, links, or sharing data ----<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black">Hi!<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black">We recently had a couple of occasions where users had mistakenly used Hydrofluoric acid in place of Hydrochloric acid during RCA cleaning. To avoid this, one of the suggestions
we have received from our OLSEH is to store HF in a different coloured bottle (currently all acids are stored in white translucent polypropylene bottles which are properly labelled). Accordingly, we had considered storing HF in opaque, brown colour HDPE bottles.
However, that was not deemed acceptable by a section of users saying bottles should be translucent so that acid level inside can be judged.<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black">Could you please let me know how small quantities of HF are stored in your respective fabs. Is there any regulation governing storage of HF, so that we could implement
the same.<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black">Thanks and regards,<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black">Savitha<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Dr. Savitha P<br>
Chief Operating Officer<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">National Nanofabrication Centre<br>
Centre for Nanoscience and Engineering<br>
Indian Institute of Science<br>
Bangalore - 560012<br>
India.<br>
Ph. +91 80 2293 3319<br>
<a href="http://www.cense.iisc.ac.in">www.cense.iisc.ac.in</a><o:p></o:p></span></p>
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