Patent ID: 10720330

Abstract:
A semiconductor device includes: a first-conductivity-type drift layer including a first-conductivity-type impurity, vacancy-oxygen-hydrogen complex defects each caused by a vacancy, an oxygen atom, and a hydrogen atom, divacancy-and-vacancy-phosphorus complex defects, having a trap density level lower than a trap density level of the vacancy-oxygen-hydrogen complex defect, and third complex defects; a plurality of donor layers provided at different depths in a depth direction of the first-conductivity-type drift layer, wherein each of the plurality of donor layers includes donors caused by the vacancy-oxygen-hydrogen complex defects, and each of the plurality of donor layers has an impurity concentration distribution that includes a first portion with a maximum impurity concentration and a second portion with a concentration gradient in which the impurity concentration is reduced from the first portion to both main surfaces of the first-conductivity-type drift layer; and a second-conductivity-type semiconductor region provided on one main surface of the first-conductivity-type drift layer.