SEMICONDUCTOR DEVICES AND METHODS OF MANUFACTURE THEREOF

摘要

A method of manufacturing a semiconductor device comprising source and drain regions (13, 14, 14a) of a first conductivity type, and a channel­accommodating region (15) of a second, opposite conductivity type which separates the source and drain regions. The device comprises a gate (11, 42) which extends adjacent to the channel-accommodating region. The method includes the steps of etching a trench (27) into the semiconductor body of the device at a location laterally spaced from that of the gate (11, 42); and implanting a second conductivity type dopant into the body through the bottom (27b) of the trench to form a second conductivity type localised region (37) in the drain region. The dimensions and doping level of the localised level of the localised region (37) in the finished device is such that the localised region and adjacent portions of the drain region provide a voltage-sustaining space­charge zone when depleted. This serves to substantially improve the trade-off between on-resistance and breakdown voltage in the resulting device in a cost effective manner.