Patent ID: 9337294
Filing Date: 2016-05-10
CPC Classification: H01L,Y10S

Claim Text:
1. A semiconductor device comprising: a substrate; a first semiconductor region formed at a front surface of the substrate, the first semiconductor region including an active element that regulates current flowing in a thickness direction of the substrate; an implantation region in which phosphorus is implanted such that a peak portion of density per unit volume is disposed at a predetermined distance from a rear surface of the substrate; and a second semiconductor region between the implantation region and the rear surface of the substrate, in which impurities of a predetermined conduction type are implanted, that is formed with a predetermined thickness, and through which the current flows, wherein a density per unit volume of phosphorus in the second semiconductor region is at most 1/10 of a density per unit volume of the impurities of the predetermined conduction type in the second semiconductor region.