论文部分内容阅读
GaAs/Ge/GaAs multilayer heterostructure material has been prepared in situ in chloride system with improved doublebubble bottle and double reaction chamber.In order to control the growth process,the effect of various parameters on the growthrate of heteroepitaxy of GaAs on Ge substrate(GaAs/Ge)and that of Ge on GaAs substrate(Ge/GaAs)has been studied andtheir growth mechanism discussed.It is found that the growth mechanism of GaAs/Ge is similar to that of GaAs/GaAs,bothare controlled by chemical reaction rate on the surface,but the growth rate of the former is much higher than that of latter due tothe catalytic effect of Ge.The growth mechanism of Ge/GaAs is temperature dependent.WhenT around 800～700℃,it is con-trolled by diffusion transport and when t<700℃,it is controlled by surface chemical reaction.On the basis of the growth mecha-nism study,a good quality GaAs/Ge/GaAs multilayer heterostructure material with smooth surface morphology and sharp in-terface was prepared under the optimum conditions.Such material is expected to be used in opto-electronic integrated devicesand double heterojunction transistor.
GaAs / Ge / GaAs multilayer heterostructure material has been prepared in situ in chloride system with improved doublebubble bottle and double reaction chamber. The effect of various parameters on the growth rate of heteroepitaxy of GaAs on Ge substrate (GaAs / Ge) and that of Ge on GaAs substrate (Ge / GaAs) has been studied and the growth mechanism discussed. It is found that the growth mechanism of GaAs / Ge is similar to that of GaAs / GaAs, bothare controlled by chemical reaction rate on the surface, but the growth rate of the former is much higher than that of a due due tothe catalytic effect of Ge. growth mechanism of Ge / GaAs is temperature dependent.When T around 800 ~ 700 ℃, it is con-trolled by diffusion transport and when t <700 ° C, it is controlled by surface chemical reaction. On the basis of the growth mecha-nism study, a good quality GaAs / Ge / GaAs multilayer heterostructure material with smooth surface morphology and sharp in-terface was prepared under t he optimum conditions. chu material is expected to be used in opto-electronic integrated devices and double heterojunction transistor.