Environmentally harmonized plasma etching processes of amorphous silicon and tungsten

A novel etching process of a-Si and W for cleaning the CVD chamber employing ECR O/sub 2/ plasma with injecting fluorocarbon radicals generated from a fluorocarbon radical source was developed for replacing green house gases such as SF/sub 6/ gas and PFC gases. We proposed a new radical control method where the generated high order fluorocarbon radicals introduced into the plasma reactor are controlled through the radical filter heated by ceramic heater. As a result, high etching rates of 104 nm/min (a-Si) and 141 nm/min (W) were obtained by controlling heater temperature in the radical filter. These results indicated that this technique has a great potential to be applicable to a novel chamber cleaning process for replacing the conventional process with green house gases.