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Hi Alex,<br>
<br>
Here at UDel the RH is (45+/-2)%. Controlling to +/- 2% is not easy
but it is doable. We fall out of spec sometimes during the shoulder
seasons (Spring and late Fall).<br>
<br>
A better way to approach humidity control is to use the dewpoint,
which is a physical quantity. Relative humidity is a calculated
quantity, i.e. it is temperature dependent. As an example, for the
same amount of moisture in the air, a higher temperature leads to a
lower relative humidity.<br>
<br>
The previous responses did a good job at explaining why humidity
control is important. To what degree you control depends on how
critical your processes are. My guess is that +/- 5% is adequate for
most labs.<br>
<br>
Cheers!<br>
<br>
<pre class="moz-signature" cols="72">iulian Codreanu, Ph.D.
Director, Nanofabrication Facility
University of Delaware
Harker ISE Lab, Room 163
221 Academy Street
Newark, DE 19716
302-831-2784
<a class="moz-txt-link-freetext" href="https://udnf.udel.edu">https://udnf.udel.edu</a></pre>
<br>
<div class="moz-cite-prefix">On 12/17/2025 12:12 PM, Alex Dixon
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:BY3PR17MB539405937CA433B1FFF1A6A3AEABA@BY3PR17MB5394.namprd17.prod.outlook.com">
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For those of you with climate controls in your cleanrooms, what
relative humidity do your keep your cleanroom at, and how
tightly do you control the fluccuations? How significant an
effect have you seen on device performance? </div>
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<br>
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Our campus facilities is doing a climate control audit and
asking any lab with special requirements to justify them. Any
info you could share would be appreceated.</div>
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<br>
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Thanks!</div>
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-Alex</div>
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<br>
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<span style="background-color: rgb(255, 255, 255);">__________________________________________________________</span></div>
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<span style="background-color: rgb(255, 255, 255);"><br>
</span></div>
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<span style="background-color: rgb(255, 255, 255);"><br>
</span></div>
<div
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class="elementToProof">
<span style="background-color: rgb(255, 255, 255);">Alex
Dixon, Ph.D. (He/Him)</span></div>
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Lab Manager</div>
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Nanofabrication and Thin Film Deposition</div>
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<span style="background-color: rgb(255, 255, 255);">Shared
Instrument Facility </span></div>
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Colorado School of Mines</div>
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<br>
</div>
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<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
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