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<div>Greetings Errol,</div>
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<div>Here at OU one of our main wet bench uses in the CR is wafer preparation for IV/VI MBE growth. Shiraki Clean is the method of choice. Its really just a fancy RCA clean with solvent metal cleaning in the beginning of the process. </div>
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<div>As our other colleagues stated… DI rinse is highly recommended post HF or any other type of acid dip. </div>
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<div>And to take it a bit further, the way the rinse is performed is very important. One must stride to employ a steady stream of decent research grade DI. A small trickle of low resistivity DI into a beaker just wont cut it. If you can provide ~18Mohm
with a high volume of flow- you will be set! You really need to have the samples placed vertical in the boat or holder. That way the DI rinse can do its thing in a uniform fashion. I've seen folks submerge the samples horizontally which proved to be
a poor way of rinse. Bubbles propagate and get stuck in between the samples/wafers. </div>
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<div>I have seen a weak flow of say ~2000ml / 4min @10Mohm DI barely cut it when your looking for a nice sheeting action of the sample. After boosting our DI system to provide an actual 17.86Mohm at gallons of flow per minute we now have excellent results
in wafer preparation.</div>
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<div>A QDR (quick dump rinse) is ideal, but that system requires some serious infrastructure. Simply stated. A good strong rinse with the highest grade (18 Mohm) DI water is the best for results and safety.</div>
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<div>I hope this helps! Don’t forget your PPE!</div>
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<div style="font-family: Calibri, sans-serif; font-size: 14px; ">-Len</div>
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<div style="font-size: 14px; "><font class="Apple-style-span" face="Helvetica"><b>Leonard E. Olona</b></font></div>
<div style="font-size: 14px; "><font class="Apple-style-span" face="Helvetica" size="2"><i>University Cleanroom Manager</i></font></div>
<div style="font-size: 14px; "><font class="Apple-style-span" face="Helvetica" size="2">University of Oklahoma</font></div>
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<div style="font-size: 14px; font-family: Calibri, sans-serif; "><font class="Apple-style-span" size="2">F: +1- 405 325-7066</font></div>
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<span style="font-weight:bold">From: </span>"Errol V. Porter" <<a href="mailto:evporte@uark.edu">evporte@uark.edu</a>><br>
<span style="font-weight:bold">Date: </span>Wednesday, February 26, 2014 4:43 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] Piranha & HF no rinse protocols<br>
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<p class="MsoNormal">Greetings,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am trying to get a consensus and feedback from the group on a wet etch process using 1<sup>st</sup> H2SO4:H2O2 (1:1) and 2<sup>nd</sup> HF:H2O (10:1) where the water rinse is omitted. If this is an acceptable practice in some special
circumstances, what safeguards to you put in place to protect the users.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Errol Porter<o:p></o:p></p>
<p class="MsoNormal">University of Arkansas / HiDEC<o:p></o:p></p>
<p class="MsoNormal">700 W. Research Center Blvd<o:p></o:p></p>
<p class="MsoNormal">Fayetteville, AR 72701<o:p></o:p></p>
<p class="MsoNormal">Tel. (479) 575-2519<o:p></o:p></p>
<p class="MsoNormal">Mobile: (479) 236-0693<o:p></o:p></p>
<p class="MsoNormal">Fax (479) 575-2719<o:p></o:p></p>
<p class="MsoNormal">email:<span style="color:#1F497D"> <a href="mailto:evporte@uark.edu">
<span style="color:blue">evporte@uark.edu</span></a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><a href="http://www.hidec.uark.edu/"><span style="color:blue">http://www.hidec.uark.edu</span></a><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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