Growth kinetics in the MOVPE of ZnSe on GaAs using zinc and selenium alkyls
Abstract
For the MOVPE growth of ZnSe on GaAs using zinc and selenium alkyls, the dependence of growth rate on growth temperature (Tg) and transport rate of source materials have been investigated. There have been observed two characteristic temperature ranges; i.e., a higher temperature range (500 < T < 600°C) where the growth rate is independent of Tg, and a lower temperature range (400 < Tg < 500°C) where the growth rate changes exponentially with temperature. The dependence of growth rate on the transport rate of various kinds of source materials including diethylzinc, dimethylzinc, diethyl selenide and dimethyl selenide clearly indicates that the growth at higher temperatures is characterized by the mass transport of Zn and Se sources and that at lower temperatures by a kinetic process occurring on the growth surface.
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