Patent ID: 9171977
Filing Date: 2015-10-27
Classification: H01L

Abstract:
1. A thyristor, comprising: a semiconductor layer having a first conductivity type and a first doping concentration; a carrier injection layer on the semiconductor layer, the carrier injection layer having the first conductivity type and a second doping concentration that is lower than the first doping concentration, wherein the carrier injection layer has a thickness greater than 1 micron; a drift layer on the carrier injection layer, the drift layer having the second conductivity type; a buffer layer having the second conductivity type between the carrier injection layer and the drift layer, wherein the carrier injection layer and the buffer layer form a p-n junction; a base layer having the first conductivity type on the drift layer; and an anode region having the second conductivity type on the base layer, wherein the carrier injection layer is thicker than the buffer layer.