ZN DIFFUSION OF IN0.5GA0.5P INVESTIGATED BY PHOTOLUMINESCENCE MEASUREMENTS

Zn diffusion of an In0.5Ga0.5P layer grown on semi-insulating GaAs sub strate by the liquid phase epitaxy technique has been investigated usi ng photoluminescence (PL) measurements. The PL spectrum shows a charac teristic emission peak of In0.5Ga0.5P at 1.934 eV after diffusion. Fro m temperature-dependent studies of this peak and depth profiling of th is luminescence, it was found that this peak behaves like D-A (donor-a cceptor) pair recombination and is associated with the interstitial Zn donor to substitutional Zn acceptor band transition. Also it was foun d that recombination due to interstitial Zn donor is dominant near the surface and decreases with increasing depth. The calculated activatio n energy of substitutional acceptor was found to be 47 meV. (C) 1997 E lsevier Science S.A.