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Hi Nathan,<br>
<br>
Please see below for some thoughts.<br>
<br>
A diluted SiH4 cylinder is considered by some folks safer but other
folks disagree. Some things to consider are the number of cylinder
changes and that SiH4 mixtures can explode if allowed to accumulate
inside various enclosures.<br>
<br>
A diluted SiH4 will require higher gas flows, which are easier to
control via the MFC because you can operate closer to its mid range.<br>
<br>
An additional line for pure He can be used to control film stress.<br>
<br>
Cheers!<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>
<div class="moz-cite-prefix">On 4/7/2025 9:49 AM, Nathan Aultman
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:BL3PR11MB633795255E0EF3EEB1C2259989AA2@BL3PR11MB6337.namprd11.prod.outlook.com">
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<p class="MsoNormal"><span style="font-size:11.0pt">Hello
Labnetwork,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">We have a
PECVD system using dilute silane (2%)/N2. Some labs with
similar systems use dilute silane (5%)/helium. We are
nearing the end of our current cylinder and will need a
replacement soon. What are the advantages and disadvantages
when choosing the dilute gas? Does choosing a helium
mixture produce more desirable films and/or quality? In
other words, is it worth it to purchase a cylinder with
helium? Also, what would be the reason(s) for using helium
as an additional process gas? E.g., a separate MFC and gas
line.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thank you
all in advance.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Times New Roman",serif;mso-ligatures:none">Nathan
C. Aultman<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Times New Roman",serif;mso-ligatures:none">University
of Central Florida<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Times New Roman",serif;mso-ligatures:none">407-823-6852<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:11.0pt;font-family:"Times New Roman",serif;mso-ligatures:none"><a
href="mailto:naultman@creol.ucf.edu"
moz-do-not-send="true"><span style="color:#0563C1">naultman@creol.ucf.edu</span></a><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
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