Channeled substrate buried heterostructure InGaAsP/InP laser employing a buried Fe ion implant for current confinement

Abstract
A channeled substrate buried heterostructure InGaAsP/InP laser is demonstrated using a hybrid technique of Fe ion implantation followed by liquid phase epitaxy. A high resistivity region is formed by the implantation and subsequent anneal of Fe into an n-type InP substrate, and this is used to provide a self-aligned current confinement barrier layer. The use of an in situ anneal prior to liquid phase epitaxy minimizes the number of processing steps. Pulsed threshold currents as low as 22 mA have been achieved on devices utilizing broad area metal contacts.