Pipeline defects in CMOS MOSFET devices caused by SWAMI isolation

Abstract

A pipeline defect which became a leakage path between source and drain in an n-channel MOSFET was identified. It was found that a 20-second Wright-etch will clearly delineate the pipe. The cause of the pipeline was the improper SWAMI (side wall masked isolation) etch which generated stress at the island corners. This stress generated high density dislocation lines which made vacancies readily available for enhanced phosphorus diffusion.<>