POWER SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To reduce the number of manufacturing processes of a power semiconductor device with a super junction structure.SOLUTION: A method of manufacturing a power semiconductor device includes: a step of forming a plurality of first second-conductivity-type impurity injection layers; a step of forming a first trench; a step of forming an epitaxial layer of a first conductivity type; a step of forming a plurality of second second-conductivity-type impurity injection layers; a step of forming a second trench; a step of forming a third semiconductor layer of the first conductivity type; a step of diffusion; and a step of forming a fourth semiconductor layer of a second conductivity type. The first trench 5 is formed in a second semiconductor layer 2 from a surface of the second semiconductor layer 2 between a first non-injection region 7a and the first second-conductivity-type impurity injection layers 4a. The second trench 5 is formed in the epitaxial layer 2a from a surface of the epitaxial layer 2a directly above the first trench 5 between a second non-injection region 7a and the second second-conductivity-type impurity injection layers 4a.