Dominance of surface recombination current in planar, Be-implanted GaAs p-n junctions prepared by rapid thermal annealing

Abstract

Rapid thermal annealing with incoherent light was used to fabricate planar, Be-implanted p-n junctions in GaAs. Diodes of varying diameter were used to determine if the residual implant damage would cause the space-charge recombination current to dominate the surface recombination current. Unpassivated diodes are dominated by surface recombination over the 20–150 μm range of diameters investigated. Passivation of diode structures with a surface layer of high-resistivity Al0.4Ga0.6As grown by metalorganic chemical vapor deposition resulted in a significant reduction of surface recombination current and permitted the measurement of the space-charge recombination current. The space-charge recombination current for these diodes was found to be similar in value to that previously reported for Zn-diffused GaAs junctions.