Patent ID: 6838703

Claim:
A nitride-based semiconductor laser device comprising: (A) a first contacting layer formed on a substrate; (B) a first electrode formed on the first contacting layer; (C) a first cladding layer formed on the first contacting layer; (D) an active layer formed on the first cladding layer; (E) a second cladding layer formed on the active layer; (F) a second contacting layer formed on the second cladding layer; (G) a second electrode formed on the second contacting layer, the second cladding layer comprising a lower layer and an upper layer, the first contacting layer, the first cladding layer, the active layer, the second cladding layer and the second contacting layer each being composed of a nitride-based compound semiconductor layer, the first cladding layer, the active layer and the lower layer of the second cladding layer forming a mesa structure, the upper layer of the second cladding layer and the second contacting layer having a ridge structure having a width smaller than a width of the mesa structure, the second electrode having a width substantially the same as a width of the second contacting layer at an interface of the second contacting layer and the electrode; an insulating layer formed on the portions of the lower layer of the second cladding layer which portions correspond to a top surface of the mesa structure, said insulating layer covering at least part of each of both side surfaces of the upper layer of the second cladding layer; and a metal layer formed on a top surface of the insulating layer and a top surface of the second electrode such that the metal layer continues from the top surface of the insulating layer to the top surface of the second electrode, said metal layer having a width substantially the same as the width of the mesa structure.