Method for improved sputter etch processing

摘要

Method for processing a semiconductor substrate in a chamber comprising the steps of establishing preprocess conditions in the chamber, executing a two-step plasma ignition, processing the substrate, executing a two-step plasma power down and executing a two-step substrate dechuck. A "softer" ignition of a plasma in two steps reduces DC bias spikes on the substrate. Reducing DC bias spikes reduces processing anomalies such as excess charge retention in the wafer after removing the chucking voltage and wafer repulsion and plasma discontinuity during processing. Additionally, the plasma ramp down after processing allows adequate time for discharging of residual charges in the wafer which allows for more reliable removal of the substrate from the chamber (dechucking).