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<span style="font-size: 11pt; color: black;">Dear Labnetwork community,</span><o:p class="ContentPasted0" style="font-family: inherit; font-size: 11pt; font-style: inherit; font-variant-ligatures: inherit; font-variant-caps: inherit; font-weight: inherit;"> </o:p><br>
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<span style="font-size: 11pt; color: black;" class="ContentPasted0">I am having an issue with magnetron-sputtering of tantalum with DC power. After a few minutes of sputtering Ta glow spots appear on the surface of the target that eventually cause the plasma
to distinguish. <span style="border: 1pt none windowtext; padding: 0cm; background: white;" class="ContentPasted0"> I have loaded two fresh 0.31”-thick Ta targets, but both times the same problem occurred, and both times it generated enough particles in a
short amount of time ( about 2 hours of sputtering, accumulatively) that led to shorting of the source.<o:p class="ContentPasted0"> </o:p></span></span></p>
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<span class="ContentPasted0" style="background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial; font-family: Calibri, sans-serif; font-size: 11pt; border-width: 1pt; border-style: none; border-color: windowtext; padding: 0cm; color: black;">I
suspected that this might be a cooling issue, but there is enough flow rate at the sputtering source,
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and I use indium thin foil for thermal contact between the cathode and the target </span></span><span class="ContentPasted0 ContentPasted2" style="border-width: 1pt; border-style: none; border-color: windowtext; font-size: 11pt; padding: 0cm; color: black;">(recommended
by the company- MeiVac).</span><span style="font-size: 11pt; color: black;"><o:p class="ContentPasted0 ContentPasted2"> </o:p></span></p>
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<span style="font-size: 11pt; border: 1pt none windowtext; padding: 0cm; background: white; color: black;" class="ContentPasted0">Have you experienced such a problem? I am wondering if this could be an issue with the sputtering source or could somehow the two
Ta targets I loaded have been compromised? <o:p class="ContentPasted0"> </o:p></span></p>
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<span style="font-size: 11pt; border: 1pt none windowtext; padding: 0cm; background: white; color: black;" class="ContentPasted0">Thank you very much.<o:p class="ContentPasted0"> </o:p></span></p>
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<span style="font-size: 11pt; border: 1pt none windowtext; padding: 0cm; background: white; color: black;" class="ContentPasted0">Best regards,<o:p class="ContentPasted0"> </o:p></span></p>
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<span style="font-size: 11pt; border: 1pt none windowtext; padding: 0cm; background: white; color: black;" class="ContentPasted0">Saba Sadeghi<o:p class="ContentPasted0"> </o:p></span></p>
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<span style="font-size: 11pt; border: 1pt none windowtext; padding: 0cm; background: white; color: black;" class="ContentPasted0">IQC, University of Waterloo<o:p class="ContentPasted0"> </o:p></span></p>
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<span style="font-size: 11pt; color: black;"><o:p class="ContentPasted0"> </o:p></span></p>
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