Characterization of the Descum Process for Various Silicon Substrates Doping

Abstract

The descum process is temperature-sensitive process. It has been demonstrated that the process is very sensitive to silicon substrate doping, which impacts wafer heating. A higher doping level caused much higher resist removal when the descum process was ran in a reactor that also ran dry strip processes. The higher level of resist removal was the result of higher wafer surface temperature. The likely causes for higher wafer surface temperature are lower thermal conductivity and higher emissivity of the highly doped wafer substrate.