Application of controlling gas valves to reduce particles from CVD process

摘要

The present invention proposes an application of controlling gas valves to reduce particles from the CVD process. First, the actions of opening and closing a gas valve are added to let particles possibly adhering on the gas valve fall during the idle period between the CVD processes of a wafer and the next wafer. Next, an inert gas is led in to purge the gas valve and the reaction chamber. Finally, a gas-extracting means is used to extract the gas out. The actions of opening and closing the gas valve only take a few seconds so that the time of the next wafer entering the reaction chamber to perform the CVD process will not be influenced. The present invention has the advantage of increasing the yield of wafer while the production is not influenced and the original fabrication equipments need not be changed.