<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Dear micro/nano cleanroom colleagues:<div><br></div><div>Please critique the following thought process and give your insight which approach is best in planning the process gas piping for a new installation. </div><div><br></div><div>Which do you use (VMP/distributed) in your new facility or new tool installations and are you happy?</div><div><br></div><div>If VMP's, what is the threshold number of tools for which you consider it justifiable to use VMP's?</div><div><br></div><div><b>valve manifold panels:</b></div><div>pro's: </div><div>• clean, organized installation, flexible to any future installation, populated when needed</div><div>• system contamination attained by ability to purge regulators with venturi</div><div>• leaks or failures within isolated runs do not contaminate other processes or cause downtime on other tools</div><div>• prevent cross-talk between process MFC's, using the same gases</div><div>• does not cause system downtime when installing new processes</div><div><br></div><div>Con's</div><div>• up front cost is greater, though not sure how much</div><div><br></div><div><b>Process gases distributed through shared supply line, and laterals / drops:</b></div><div>pro's:</div><div>• Up front cost is lower (not sure how much-- it depends...)</div><div>• cross-talk can be minimized by a regulator at each tool</div><div><br></div><div>Con's:</div><div>• system downtime for all tools sharing the gases during</div><div>• cost may be comparable depending upon number of valved drops, and how good the planning is for predicting future installation points</div><div>• see pro's above in VMP</div><div><br></div><div>Thank you all!</div><div><br></div><div>--Ian</div><br><br><div apple-content-edited="true">
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="orphans: 2; text-indent: 0px; widows: 2; -webkit-text-decorations-in-effect: none; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="orphans: 2; text-indent: 0px; widows: 2; -webkit-text-decorations-in-effect: none; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; ">********************************************<br>Ian R. Harvey, Ph.D.<br>Research Associate Professor<br>Department of Mechanical Engineering</div><div style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; ">Adjunct Associate Professor</div><div style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; ">Department of Electrical & Computer Engineering<br>2511 SMBB (USTAR)<br><br>Associate Director,</div><div style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; ">Utah Nanofab & </div><div>Micron Microscopy Core</div><div><br></div><div>801/585-6162 (voicemail)<br>801/581-5676 (lab main number)<br><a href="http://www.nanofab.utah.edu">www.nanofab.utah.edu</a><br><br><b>mail to:</b></div><div style="font-weight: normal; ">Utah Nanofab / University of Utah</div><div style="font-weight: normal; ">36 South Wasatch Drive</div><div style="font-weight: normal; ">Suite 2500<br>Salt Lake City, Utah 84112-9011<br></div></div></span></div></span></div></span></div></span></span><span></span></div></body></html>