摘要 |
One or more of three different measures are taken to preheat a wafer before it is loaded into direct contact with a wafer holder, in order to provide optimal throughput while reducing the risk of thermal shock to the wafer. The first measure is to move the wafer holder to a raised position prior to inserting the wafer into the reaction chamber and holding the wafer above the wafer holder. The second measure is to provide an increased flow rate of a heat-conductive gas (such as Hs purge gas) through the chamber prior to inserting the wafer therein. The third measure is to provide a power bias to radiative heat elements (e.g., heat lamps) above the reaction chamber.
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