Mitigation of well proximity effect in integrated circuits

摘要

A hard implantation mask layer is formed on a semiconductor wafer. An etch mask layer is formed on the hard implantation mask layer and patterned. The hard implantation mask layer is etched to form a well implantation pattern and ions are implanted into the semiconductor wafer to form wells in the semiconductor wafer, in areas where the semiconductor wafer is not covered by the well implantation mask.