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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Xiaojin,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'> After reading your note and relating it to past experiences with cryo pumps over the years you could be experiencing numerous problems. There are numerous things that could cause your issue you should inspect the arrays in the pump and numerous other things but the easiest check that you can do to start is to take a look at your helium pressure, you should have a send and return gauge on your compressor and they should be operating within limits that are required by the manufacturer. Check those gauges first and see if they are within the specified tolerance, you may be either low on helium or of the Delta P is to great you may have a dirty adsorber. If your helium pressure has dropped below what the manufacturer recommends you can simply recharge it and perform a regeneration and you should be fine (given you don’t have a helium leak somewhere), make sure to use 6.0 grade helium and the proper helium gas filling manifold and recharging procedure. I have pasted a troubleshooting guide for you from a CTI system but a lot of the principles will apply to your pump. If you still have problems feel free to give me a call at the numbers below.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-top:.05pt;line-height:8.5pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:8.5pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:1.45pt;margin-right:0in;margin-bottom:0in;margin-left:137.95pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><a name=bookmark0></a><b><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.25pt'>Table</span></b><b><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> 4-1:<span style='letter-spacing:.1pt'> </span><span style='letter-spacing:-.1pt'>Troubleshooting</span> <span style='letter-spacing:-.1pt'>Procedures</span></span></b><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p><p class=MsoNormal style='margin-top:.35pt;line-height:6.0pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:6.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 style='margin-left:5.75pt;border-collapse:collapse'><tr style='height:26.05pt;mso-height-rule:exactly'><td width=208 valign=top style='width:155.95pt;border:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:26.05pt;mso-height-rule:exactly'><p class=MsoNormal align=center style='mso-margin-top-alt:.05in;margin-right:.7pt;margin-bottom:0in;margin-left:0in;margin-bottom:.0001pt;text-align:center;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Problem<o:p></o:p></span></p></td><td width=203 valign=top style='width:152.3pt;border-top:solid black 2.25pt;border-left:none;border-bottom:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:26.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:.05in;margin-right:7.1pt;margin-bottom:0in;margin-left:39.65pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Possible</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> Cause<o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border:solid black 2.25pt;border-left:none;padding:0in 0in 0in 0in;height:26.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:.05in;margin-right:3.75pt;margin-bottom:0in;margin-left:33.75pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Corrective</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:.05pt'> </span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Action<o:p></o:p></span></p></td></tr><tr style='height:105.9pt;mso-height-rule:exactly'><td width=208 rowspan=6 valign=top style='width:155.95pt;border-top:none;border-left:solid black 2.25pt;border-bottom:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:105.9pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:1.55pt;margin-right:7.85pt;margin-bottom:0in;margin-left:4.85pt;margin-bottom:.0001pt;text-align:justify;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>High</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>base</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>pressure</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>of</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>vacuum</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:1.4pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>system, </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>and<span style='letter-spacing:-.05pt'> </span>a<span style='letter-spacing:-.05pt'> cryopump tem-</span><span style='letter-spacing:1.15pt'> </span><span style='letter-spacing:-.05pt'>perature <i>below</i></span><i><span style='letter-spacing:.05pt'> </span></i><span style='letter-spacing:-.05pt'>20K.</span><o:p></o:p></span></p><p class=MsoNormal style='line-height:12.0pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:7.85pt;margin-bottom:0in;margin-left:4.85pt;margin-bottom:.0001pt;text-align:justify;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>High</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>base</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>pressure</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>of</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.9pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>vacuum</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:1.4pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>system, </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>and<span style='letter-spacing:-.05pt'> </span>a<span style='letter-spacing:-.05pt'> cryopump tem-</span><span style='letter-spacing:1.15pt'> </span><span style='letter-spacing:-.05pt'>perature <i>above</i></span><i><span style='letter-spacing:.05pt'> </span></i><span style='letter-spacing:-.05pt'>20K.</span><o:p></o:p></span></p></td><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:105.9pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:1.55pt;margin-right:7.1pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.1pt'>Air-to-vacuum</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'> leak in vac-</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:1.5pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>uum <span style='letter-spacing:-.05pt'>system</span><span style='letter-spacing:-.1pt'> </span>or<span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>in</span> cryopump.<o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:105.9pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:1.55pt;margin-right:3.75pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Check cryopump relief</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:.05pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>valve</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:1.35pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>for<span style='letter-spacing:-.05pt'> proper</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>seating.</span><o:p></o:p></span></p><p class=MsoNormal style='margin-top:.95pt;line-height:13.0pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:13.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:3.75pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Check cryopump for</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:.05pt'> </span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>leaks.</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p><p class=MsoNormal style='margin-top:.3pt;line-height:14.0pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:14.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:3.75pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:100%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Check vacuum chamber and</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:1.0pt'> </span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:.05pt'>H</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.1pt'>i</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:.05pt'>-</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-1.35pt'>V</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>a</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif"'>c<span style='letter-spacing:-.05pt'> v</span><span style='letter-spacing:.05pt'>a</span>lve<span style='letter-spacing:-.05pt'> fo</span>r<span style='letter-spacing:-.05pt'> </span>l<span style='letter-spacing:.05pt'>e</span><span style='letter-spacing:-.05pt'>aks.</span><o:p></o:p></span></p></td></tr><tr style='height:92.05pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:92.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:7.1pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>High partial pressure of non-</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:1.3pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>condensables</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'> (helium,<span style='letter-spacing:1.1pt'> </span>hydrogen, or<span style='letter-spacing:.05pt'> </span>neon) within <span style='letter-spacing:-.05pt'>the cryopump because</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>the</span><span style='letter-spacing:1.4pt'> </span><span style='letter-spacing:-.05pt'>15K array </span>has<span style='letter-spacing:-.05pt'> reached full</span><span style='letter-spacing:1.05pt'> </span><span style='letter-spacing:-.15pt'>capacity.</span><o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:92.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:3.75pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Regenerate the cryopump </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>as<span style='letter-spacing:1.5pt'> </span>described in<span style='letter-spacing:-.2pt'> </span><b><span style='letter-spacing:-.05pt'>Section</span> 3<span style='letter-spacing:-.05pt'> </span>-<span style='letter-spacing:1.2pt'> </span><span style='letter-spacing:-.05pt'>Regeneration</span></b><span style='letter-spacing:-.05pt'>.</span><o:p></o:p></span></p></td></tr><tr style='height:63.95pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:63.95pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.4pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>One of</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:.05pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>the</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:.05pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>arrays is loose,</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:1.5pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>which is <span style='letter-spacing:-.05pt'>preventing</span> good<span style='letter-spacing:1.45pt'> </span><span style='letter-spacing:-.05pt'>thermal</span><span style='letter-spacing:-.5pt'> </span><span style='letter-spacing:-.05pt'>contact</span><span style='letter-spacing:-.6pt'> </span>with<span style='letter-spacing:-.6pt'> </span>the<span style='letter-spacing:-.55pt'> </span><span style='letter-spacing:-.05pt'>cold</span><span style='letter-spacing:1.35pt'> </span><span style='letter-spacing:-.05pt'>station.</span><o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:63.95pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.4pt;margin-right:5.8pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;text-align:justify;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.25pt'>Warm</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'> the cryopump <span style='letter-spacing:-.05pt'>to</span> <span style='letter-spacing:-.05pt'>ambi-</span><span style='letter-spacing:1.3pt'> </span>ent<span style='letter-spacing:-.4pt'> </span><span style='letter-spacing:-.05pt'>temperature</span><span style='letter-spacing:-.4pt'> </span><span style='letter-spacing:-.05pt'>and</span><span style='letter-spacing:-.3pt'> </span><span style='letter-spacing:-.05pt'>retighten</span><span style='letter-spacing:1.35pt'> </span>the <span style='letter-spacing:-.05pt'>array</span> <span style='letter-spacing:-.05pt'>mounting</span> <span style='letter-spacing:-.05pt'>screws</span> to<span style='letter-spacing:1.35pt'> </span>15 -<span style='letter-spacing:.05pt'> </span>20 <span style='letter-spacing:-.05pt'>in.</span> lbs.<o:p></o:p></span></p></td></tr><tr style='height:105.95pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:105.95pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:100%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Decrease in cryopump cold</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:1.05pt'> </span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>head</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif"'> <span style='letter-spacing:-.05pt'>performance.</span><o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:105.95pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:3.75pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>If the<span style='letter-spacing:-.05pt'> helium</span> <span style='letter-spacing:-.05pt'>return</span> <span style='letter-spacing:-.05pt'>pressure</span><span style='letter-spacing:1.75pt'> </span><span style='letter-spacing:-.05pt'>gauge reads below the nor-</span><span style='letter-spacing:1.15pt'> </span><span style='letter-spacing:-.05pt'>mal-operating return pres-</span><span style='letter-spacing:1.45pt'> </span>sure<span style='letter-spacing:-.05pt'> </span>60-85 psig (415-590<span style='letter-spacing:1.05pt'> </span><span style='letter-spacing:-.05pt'>kPa), add gas as described in</span><span style='letter-spacing:1.45pt'> </span>the<span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>appropriate</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>Compressor</span><span style='letter-spacing:1.65pt'> </span><span style='letter-spacing:-.05pt'>manual.</span><o:p></o:p></span></p></td></tr><tr style='height:92.05pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:92.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:7.1pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>High partial pressure of non-</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:1.3pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>condensables</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'> (helium,<span style='letter-spacing:1.1pt'> </span>hydrogen, or<span style='letter-spacing:.05pt'> </span>neon) within <span style='letter-spacing:-.05pt'>the cryopump because</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>the</span><span style='letter-spacing:1.4pt'> </span><span style='letter-spacing:-.05pt'>15K array </span>has<span style='letter-spacing:-.05pt'> reached full</span><span style='letter-spacing:1.05pt'> </span><span style='letter-spacing:-.15pt'>capacity.</span><o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:92.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:3.75pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Regenerate the cryopump </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>as<span style='letter-spacing:1.5pt'> </span>described in<span style='letter-spacing:-.2pt'> </span><b><span style='letter-spacing:-.05pt'>Section</span> 3<span style='letter-spacing:-.05pt'> </span>-<span style='letter-spacing:1.2pt'> </span><span style='letter-spacing:-.05pt'>Regeneration</span></b><span style='letter-spacing:-.05pt'>.</span><o:p></o:p></span></p></td></tr><tr style='height:78.05pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:78.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:7.1pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:100%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Excessive</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif"'> <span style='letter-spacing:-.05pt'>thermal</span> <span style='letter-spacing:-.05pt'>load</span> on<span style='letter-spacing:1.35pt'> </span><span style='letter-spacing:-.05pt'>frontal</span><span style='letter-spacing:-.1pt'> </span><span style='letter-spacing:-.15pt'>array.</span><o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 2.25pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:78.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:8.45pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Reduce </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>the<span style='letter-spacing:-.05pt'> thermal</span> <span style='letter-spacing:-.05pt'>radiation</span><span style='letter-spacing:1.85pt'> </span>load<span style='letter-spacing:-.15pt'> </span>by 1)<span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>shielding</span> the cry-<span style='letter-spacing:1.35pt'> </span><span style='letter-spacing:-.05pt'>opump or 2)</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>lowering the</span><span style='letter-spacing:1.3pt'> </span><span style='letter-spacing:-.05pt'>temperature</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>of the radiating</span><span style='letter-spacing:1.4pt'> </span><span style='letter-spacing:-.05pt'>surface.</span><o:p></o:p></span></p></td></tr></table><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:.1in;margin-right:0in;margin-bottom:0in;margin-left:105.4pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><b><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.25pt'>Table</span></b><b><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> 4-1:<span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.1pt'>Troubleshooting</span> <span style='letter-spacing:-.1pt'>Procedures</span> <span style='letter-spacing:-.05pt'>(Continued)</span></span></b><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p><p class=MsoNormal style='margin-top:.35pt;line-height:6.0pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:6.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 style='margin-left:5.75pt;border-collapse:collapse'><tr style='height:26.05pt;mso-height-rule:exactly'><td width=208 valign=top style='width:155.95pt;border:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:26.05pt;mso-height-rule:exactly'><p class=MsoNormal align=center style='mso-margin-top-alt:.05in;margin-right:.7pt;margin-bottom:0in;margin-left:0in;margin-bottom:.0001pt;text-align:center;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Problem<o:p></o:p></span></p></td><td width=203 valign=top style='width:152.3pt;border-top:solid black 2.25pt;border-left:none;border-bottom:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:26.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:.05in;margin-right:0in;margin-bottom:0in;margin-left:39.65pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Possible</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> Cause<o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border:solid black 2.25pt;border-left:none;padding:0in 0in 0in 0in;height:26.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:.05in;margin-right:0in;margin-bottom:0in;margin-left:33.75pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Corrective</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:.05pt'> </span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Action<o:p></o:p></span></p></td></tr><tr style='height:63.9pt;mso-height-rule:exactly'><td width=208 rowspan=4 valign=top style='width:155.95pt;border-top:none;border-left:solid black 2.25pt;border-bottom:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:63.9pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:1.55pt;margin-right:6.55pt;margin-bottom:0in;margin-left:4.85pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Cryopump</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'> <span style='letter-spacing:-.05pt'>fails</span> to cool down<span style='letter-spacing:1.4pt'> </span><span style='letter-spacing:-.05pt'>to</span> <span style='letter-spacing:-.05pt'>the</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>required operating tem-</span><span style='letter-spacing:1.35pt'> </span>perature<span style='letter-spacing:-.05pt'> </span>or <span style='letter-spacing:-.05pt'>takes</span> <span style='letter-spacing:-.05pt'>too</span> long to<span style='letter-spacing:1.2pt'> </span><span style='letter-spacing:-.05pt'>reach that</span> <span style='letter-spacing:-.05pt'>temperature (20K).</span><o:p></o:p></span></p></td><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:63.9pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:1.55pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Low helium <span style='letter-spacing:-.05pt'>supply</span> pressure.<o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:63.9pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:1.55pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;text-indent:.1pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>Add<span style='letter-spacing:-.15pt'> </span>gas as described in <span style='letter-spacing:-.05pt'>the</span><span style='letter-spacing:1.2pt'> </span>appropriate<span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>Compressor</span><span style='letter-spacing:1.35pt'> </span><span style='letter-spacing:-.05pt'>manual.</span><o:p></o:p></span></p></td></tr><tr style='height:50.05pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:50.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Compressor</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> problems.<o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:50.05pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>Refer<span style='letter-spacing:-.15pt'> </span><span style='letter-spacing:-.05pt'>to</span><span style='letter-spacing:-.15pt'> </span><span style='letter-spacing:-.05pt'>Troubleshooting</span><span style='letter-spacing:-.25pt'> </span>sec-<span style='letter-spacing:1.15pt'> </span>tion of the appropriate Com-<span style='letter-spacing:1.05pt'> </span><span style='letter-spacing:-.05pt'>pressor manual.</span><o:p></o:p></span></p></td></tr><tr style='height:105.95pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:105.95pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.4pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-1.35pt'>V</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>a</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:.05pt'>c</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>uum<span style='letter-spacing:-.1pt'> </span>l<span style='letter-spacing:.05pt'>e</span>ak in vacuum sys- <span style='letter-spacing:-.05pt'>tem or cryopump.</span><o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 1.0pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:105.95pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.4pt;margin-right:19.05pt;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>Check <span style='letter-spacing:-.05pt'>the</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>cryopump</span> relief<span style='letter-spacing:1.35pt'> </span><span style='letter-spacing:-.05pt'>valve</span><span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>for proper seating.</span><o:p></o:p></span></p><p class=MsoNormal style='margin-top:.95pt;line-height:13.0pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:13.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:5.7pt;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Check cryopump for</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:.05pt'> </span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>leaks.</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p><p class=MsoNormal style='margin-top:.3pt;line-height:14.0pt;mso-line-height-rule:exactly;punctuation-wrap:simple;text-autospace:none'><span style='font-size:14.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:5.7pt;line-height:100%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Check vacuum system for</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:1.25pt'> </span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>leaks.</span><span style='font-size:12.0pt;line-height:100%;font-family:"Times New Roman","serif"'><o:p></o:p></span></p></td></tr><tr style='height:92.1pt;mso-height-rule:exactly'><td width=203 valign=top style='width:152.3pt;border-top:none;border-left:none;border-bottom:solid black 2.25pt;border-right:solid black 1.0pt;padding:0in 0in 0in 0in;height:92.1pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Incomplete</span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-1.15pt'> </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>regeneration<span style='letter-spacing:-1.1pt'> </span><span style='letter-spacing:-.05pt'>may</span><span style='letter-spacing:1.2pt'> </span>not have <span style='letter-spacing:-.05pt'>fully</span> <span style='letter-spacing:-.05pt'>cleaned</span> the<span style='letter-spacing:1.0pt'> </span><span style='letter-spacing:-.05pt'>adsorbing </span><span style='letter-spacing:-.15pt'>array.</span> <span style='letter-spacing:-.05pt'>Partial pres-</span><span style='letter-spacing:1.2pt'> </span>sures of<span style='letter-spacing:.05pt'> </span><span style='letter-spacing:-.05pt'>non-condensables</span><span style='letter-spacing:1.35pt'> </span><span style='letter-spacing:-.05pt'>(hydrogen, neon or helium)</span><span style='letter-spacing:1.35pt'> </span><span style='letter-spacing:-.05pt'>may</span> <span style='letter-spacing:-.05pt'>remain.</span><o:p></o:p></span></p></td><td width=206 valign=top style='width:154.5pt;border-top:none;border-left:none;border-bottom:solid black 2.25pt;border-right:solid black 2.25pt;padding:0in 0in 0in 0in;height:92.1pt;mso-height-rule:exactly'><p class=MsoNormal style='mso-margin-top-alt:2.55pt;margin-right:0in;margin-bottom:0in;margin-left:5.7pt;margin-bottom:.0001pt;line-height:101%;punctuation-wrap:simple;text-autospace:none'><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif";letter-spacing:-.05pt'>Regenerate the cryopump </span><span style='font-size:12.0pt;line-height:101%;font-family:"Times New Roman","serif"'>as<span style='letter-spacing:1.5pt'> </span>described in<span style='letter-spacing:-.2pt'> </span><b><span style='letter-spacing:-.05pt'>Section</span> 3<span style='letter-spacing:-.05pt'> </span>-<span style='letter-spacing:1.2pt'> </span><span style='letter-spacing:-.05pt'>Regeneration</span></b><span style='letter-spacing:-.05pt'>.</span><o:p></o:p></span></p></td></tr></table><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Thank you,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:navy'>Craig Cheney<o:p></o:p></span></b></p><p class=MsoNormal><span style='color:navy'><img width=239 height=79 id="Picture_x0020_1" src="cid:image001.jpg@01CEFCC0.3EC82EB0" alt="Description: cid:image001.jpg@01C7E19F.47FFBAE0"></span><span style='font-size:12.0pt;font-family:"Times New Roman","serif";color:navy'><o:p></o:p></span></p><p class=MsoNormal><span style='color:navy'> <o:p></o:p></span></p><p class=MsoNormal><span style='color:navy'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:navy'>Desk: (608)834-4200<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:navy'>Fax: (608)834-4299<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:navy'>Cell: (608)438-8714<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Arial","sans-serif";color:navy'><o:p> </o:p></span></b></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>This e-mail transmission and any attachments to it are intended solely for the use of the individual or entity to whom it is addressed and may contain confidential and privileged information. If you are not the intended recipient, your use, forwarding, printing, storing, disseminating, distribution, or copying of this communication is prohibited. If you received this communication in error, please notify the sender immediately by replying to this message and delete it from your computer.<o:p></o:p></span></b></p></div><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> labnetwork-bounces@mtl.mit.edu [mailto:labnetwork-bounces@mtl.mit.edu] <b>On Behalf Of </b>Wang,Xiaojin<br><b>Sent:</b> Thursday, December 19, 2013 10:05 AM<br><b>To:</b> labnetwork@mtl.mit.edu<br><b>Subject:</b> [labnetwork] cryopump maintenance<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Dear colleagues:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We have a cryo-torr 8F pump on our sputtering system PVD75 manufactured by Kurt J.Lesker. It has experienced a very strange incidence lately. During the weekend, the gate valve between process chamber and cropump shut off itself and the pressure in the chamber went up to several torrs while the gate valve is supposed to open and let cropump pump the system to 10^-7 torr. The temperature of cropump went up to 215K and it was still pumping. After we regenerated the cryopump the cooling time for it to be below 20K has been doubled and the lowest temperature it can reach is 18K while it used to be 13K. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Did anyone run into this kind of incidence before and what could possibly cause it?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>What do we need to do to prevent it from happening again?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is there anyway to bring the good performance back to the pump again? <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We also have a cryopump on e-beam system. Generally, what kind of maintenance need to be done on these cryopumps so that we can maximize their lifetime?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Your valuable suggestions are very appreciated.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best wishes<o:p></o:p></p><p class=MsoNormal>Xiaojin Wang<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Senior process engineer<o:p></o:p></p><p class=MsoNormal>Micro/nano technology center<o:p></o:p></p><p class=MsoNormal>University of Louisville<o:p></o:p></p></div></body></html>