Group iii nitride compound semiconductor laser

Abstract

A semiconductor laser comprises a sapphire substrate , an AlN buffer layer , Si-doped GaN n-layer , Si-doped Al Ga N n-cladding layer , Si-doped GaN n-guide layer , an active layer having multiple quantum well (MQW) structure in which about 35 Å in thickness of GaN barrier layer and about 35 Å in thickness of Ga In N well layer are laminated alternately, Mg-doped GaN p-guide layer , Mg-doped Al Ga N p-cladding layer , and Mg-doped GaN p-contact layer are formed successively thereon. A ridged hole injection part B which contacts to a ridged resonator part A is formed to have the same width as the width w of an Ni electrode . Holes transmitted from the Ni electrode are injected to the active layer with high current density, and electric current threshold for laser oscillation can be decreased. Electric current threshold can be improved more effectively by forming also the p-guide layer to have the same width as the width w of the Ni electrode