Diffusion of Zinc and Tin in Indium Antimonide

Abstract

The diffusion of zinc and tin in single-crystal and polycrystalline InSb has been studied with the radio-tracer technique. The temperature dependence of the diffusion coefficients can be represented by: $D(\mathrm{Zn})=1.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}\mathrm{exp}(\ensuremath{-}\frac{0.86}{\mathrm{kT}})$ c${\mathrm{m}}^{2}$/sec and $D(\mathrm{Sn})=5.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}\mathrm{exp}(\ensuremath{-}\frac{0.75}{\mathrm{kT}})$ ${\mathrm{cm}}^{2}$/sec in single-crystal InSb; and $D(\mathrm{Zn})=1.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}\mathrm{exp}(\ensuremath{-}\frac{0.85}{\mathrm{kT}})$ ${\mathrm{cm}}^{2}$/sec in polycrystalline InSb, the activation energies being in electron volts. From the penetration curves, it appears that in polycrystalline InSb the zinc diffusion is a volume diffusion while the tin diffusion is mainly a grain boundary diffusion. The different behaviors of zinc and tin in InSb are discussed on the basis of one-type and two-type vacancy mechanisms.