Patent ID: 7596160

Claim:
A nitride semiconductor laser comprising: an n-type cladding layer, an active layer, a guide layer, a p-type cladding layer, and a p-type contact layer which are all formed over a semiconductor substrate, wherein: the cross section of the p-type cladding layer partially includes an inverted trapezoidal portion, a semi-insulating AlGaN layer is buried on both lateral sides of the inverted trapezoidal portion of the p-type cladding layer, and the p-type cladding layer lies over the AlGaN layer continuously with the inverted trapezoidal portion of the p-type cladding layer, and the p-type contact layer lies over the p-type cladding layer, a mesa stripe as the inverted trapezoidal portion of the p-type cladding layer extends parallel to <1-100>, and a surface orientation of a tilted surface of the AlGaN layer in the inverted trapezoidal portion is (11-22), and the growth direction is in the semiconductor substrate <0001> direction, and GaN layers lie on the tilted surface, upper surface and lower surface of the AlGaN layer.