Deep-level distributions near p-n junctions in LPE GaAs

Deep-level concentrations near p-n junctions in LPE GaAs have been studied by the capacitance spectroscopy method. Two deep levels which are characteristic of LPE growth were measured within a few μm of the junction in both p+n and n+p diodes. The results indicate a uniform concentration of (6–9) ×1014 cm−3 for these levels in n-type GaAs, but an extremely large variation from 3×1013 to 1015 cm−3 within 1 μm of the junction in p-type GaAs. In addition some samples show Cu and Fe contamination in the low 1014-cm−3 range due to diffusion from the LPE-substrate interface.