SURFACE RECOMBINATION VELOCITIES ON PROCESSED INGAP P-N-JUNCTIONS

InGaP p-n junction mesa diodes were fabricated. by wet or dry etching, and the surface recombination velocities (S(v) measured from the size dependence of the current density-voltage characteristics. Within exp erimental error, the dry etching does not increase the S values, which are in the range 4.4-5.2 X 10(4) cm s-1. Subsequent low temperature a nnealing or plasma exposure did not degrade the surface properties of the mesa diodes, and some improvement was observed with (NH4)2Sx treat ment. While the InGaP diodes are relatively insensitive to typical pro cessing steps, comparable AlGaAs p-n junction show much larger changes in surface recombination velocities.