Specific Process Knowledge/Thin film deposition/Temescal: Difference between revisions
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If the material you are depositing requires a lot of heat to evaporate, the substrates may get warm during the deposition. | If the material you are depositing requires a lot of heat to evaporate, the substrates may get warm during the deposition. | ||
A temperature test of a 100 nm Al deposition at 10 Å/s showed that the back of the wafer stays below 37 <sup>o</sup>C. The same is true for 10 nm Ti plus 90 nm Au at 10 Å/s. In contrast, deposition of 100 nm Nb at 2 Å/s heated the substrate to above 104 <sup>o</sup>C (but the back of the wafer stayed at less than 110 <sup>o</sup>C). Deposition of 60 nm W at about 1 Å/s heated the substrate to more than | A temperature test of a 100 nm Al deposition at 10 Å/s showed that the back of the wafer stays below 37 <sup>o</sup>C. The same is true for 10 nm Ti plus 90 nm Au at 10 Å/s. In contrast, deposition of 100 nm Nb at 2 Å/s heated the substrate to above 104 <sup>o</sup>C (but the back of the wafer stayed at less than 110 <sup>o</sup>C). Deposition of 60 nm W at about 1 Å/s heated the substrate to more than 123 <sup>o</sup>C. | ||
You may get some idea of how much the substrate will be heated by looking at the temperature required to give a reasonable vapor pressure for the evaporation. You can find a collection of Honig's vapor pressure curves at the bottom of [https://old.mcallister.com/vacuum.html this page (external link)]. | You may get some idea of how much the substrate will be heated by looking at the temperature required to give a reasonable vapor pressure for the evaporation. You can find a collection of Honig's vapor pressure curves at the bottom of [https://old.mcallister.com/vacuum.html this page (external link)]. | ||