A stripe heater was used to diffuse Zn into semi-insulating, or n-type, (001) samples from a thin spun-on silica film. The diffusion profiles were determined by means of secondary ion mass spectrometry and capacitance-voltage measurements. The diffusion depth and activation energy of the effective diffusion coefficient were compared with published data on Zn ampoule diffusion. An activation energy of 1.35eV was found for the diffusion of Zn in semi-insulating InP. An expression for the effective diffusion coefficient of Zn in InP was derived and was compared with the results of a Boltzmann-Matano analysis of diffusion profiles. It was concluded that the Zn diffusion could be explained by an interstitial-substitutional model, in which Zn diffused as a singly positively charged interstitial and acted as an acceptor by filling an In vacancy.

Rapid Thermal Processing of Zinc Diffusion in Indium Phosphide. U.Schade, P.Enders: Semiconductor Science and Technology, 1992, 7[6], 752-7