Patent ID: 6642577
Filing Date: 2003-11-04
Classification: H01L

Abstract:
A semiconductor device comprising:a semiconductor substrate of a first conductivity type having a main surface that includes a power MOSFET formation region having a first trench for forming a power MOSFET thereon and a peripheral device formation region having a second trench for forming a peripheral device thereon, the semiconductor substrate surrounding the first trench being as a drain of the power MOSFET; a well layer of a second conductivity type disposed in the second trench of the peripheral device formation region; wherein the MOSFET includes: a drift region of a first conductivity type disposed in the first trench and having an impurity concentration lower than that of the semiconductor substrate; a base region of the second conductivity type formed in the drift region and extending from the main surface in a perpendicular direction with respect to the main surface; and a source of the first conductivity type formed in the base region and extending from the main surface in the perpendicular direction.