Zinc diffusion in InAsP/InGaAs heterostructures

A systematic study of the sealed ampoule diffusion of zinc into epitaxially grown InP, In(0.53)Gs(0.47)As, In0.70Ga0.30As, In0.82Ga0.18As, and through the InAsP/InGaAs interface is presented. Diffusion depths were measured us ing cleave-and-stain techniques, electrochemical profiling, and secondary i on mass spectroscopy. The diffusion coefficients, D = D(o)e(-Ea/kT), were d erived. For InP, D-0 = 4.82 x 10(-2)cm(2)/sec and E-a = 1.63 eV and for In0 .53Ga0.47As, D-0 = 2.02 x 10(4)cm(2)/sec and E-a = 2.63 eV. Diffusion into the heteroepitaxial structures used in the fabrication of planar PIN photod iodes is dominated by the effects of the InP/InGaAs interface.