A method of manufacturing a semiconductor device capable of providing a metal oxide semiconductor field effect transistor (MOSFET) having an improved threshold voltage

摘要

In a method of manufacturing a semiconductor device using a semiconductor substrate 1, boron ions 4 are implanted into a semiconductor substrate from a trench 3 formed in the semiconductor substrate. The trench is defined by a plurality of side surfaces and a base surface extending between the side surfaces. Boron ions are implanted through the side surfaces and the base surface. It is preferable to fill the trench with a separation material to provide trench isolation extending over the p-well 7 and the n-well 8.