A novel technique to fabricate GaInAsP/InP buried heterostructure laser diodes

Abstract

A chemical etching process to obtain a double heterostructure of InP-GaInAsP-InP with a very narrow active layer width is proposed in which three layers are etched preferentially. The quaternary layer works as the inner etching mask; the cladding layers above and below the active layer show reversed-mesa and normal-mesa shapes, respectively. The method is used to fabricate a buried heterostructure laser which lases at 1.3 μm on the p-type InP substrate. The fundamental lateral mode operation with threshold current as low as 15 mA is achieved with 0.8-μm active layer width.