Orientation Dependent p-type Conversion of Fe:InP in Hydride VPE Regrown EMBH Lasers.

We have studied semi-insulating Fe:InP regrowth of etched mesa buried heterostructure lasers by hydride vapor phase epitaxy. Type-sensitive staining and electron beam induced current photographs have shown that regions near the original etched mesa are p- type instead of semi-insulating in a number of our wafers. These regions begin and end on distinct crystal boundaries, indicating that the p-type conversion is not due to simple diffusion of Zn out of the laser base structure, but is associated with uncontrolled growth off {111} sub (In) crystal planes.