An experimental investigation of Zn diffusion into InP and InGaAs

In this report, we investigate the profiles of zinc (Zn) in n-type InP <100> single crystal wafers and InGaAs epitaxial film prepared by semi-closed ampoule Zn diffusion. The different annealing effect on junction depth and concentration for InP and InGaAs is studied, and the difference is tentatively ascribed to solubility for each material. The maximum net acceptor concentration in InP changes from 3.3 x 10(17) cm(-3) to 3.3 x 10(11) cm(-1) before and after annealing, and the later value is close to the solubility limit for closed-ampoule Zn diffusion InP. Annealing does not make the maximum net acceptor concentration and depth in InGaAs change much. Our experiments show that Zn diffusion InGaAs can be used as a good ohmic contact material for photoelectric devices due to its high acceptor concentration.