Al free active region high power laser diode array on misoriented wafers

Nowadays, high power laser diodes are widely used in many applications due to their high wall plug efficiency, improved long-term reliability, and small size in addition to reductions in their cost. One of the main concerns in growth of InGaP/InGaAsP material systems using MOCVD is an indium carry over. It occurs when a relatively indium poor InGaAsP layer is grown on an InGaP layer. It is well known that the use of an intermediate layer such as GaP reduces the indium carry over. Also there has been a report that the use of an intermediate layer alone is not sufficient to suppress the indium carry over when a MOCVD system with large volume reactor is used. In this paper we present properties of 808 nm laser diodes grown on GaAs wafers having different misorientation angles. It is found that a reduction of indium carry over can be achieved by using misoriented GaAs wafers. This also leads to significantly improved L-I characteristics of lasers. The results are shown of room temperature photoluminescence measurements in InGaP/InGaAsP/InGaP single quantum well structures.