Method for fabricating a planar buried heterostructure laser diode

Abstract

Disclosed is a method for fabricating a planar buried heterostructure laser diode, comprising the steps of sequentially forming a first clad layer, an undoped active layer and a second clad layer on a substrate so as to complete a first crystal growth; forming a patterned mask layer on the second clad layer; non-selectively etching the second clad layer, the active layer, the first clad layer and the substrate using the mask layer as an etching mask; selectively etching the substrate and the first and second layers; sequentially forming a first and second current blocking layers on a structure formed by the selective etching step so as to complete a second crystal growth; sequentially forming a third clad layer and an ohmic contact layer thereon after removal of the mask layer so as to complete a third crystal growth; and forming a first electrode on a rear surface of the substrate and forming a second electrode on a surface of the third clad layer. By the method, a leakage current induced in an interface between the active layer and the first current blocking layer provided therein can be reduced in proportion to a distance between the active layer and the second current blocking layer formed on the first current blocking layer, and therefore performance of the laser diode can be enhanced.