Development of characterization system for strain distribution at semiconductor heterojunction interfaces

在这个研究项目中，我们研究了一些半导体异质结界面处的界面应力，并开发了一个新的异质界面应力二维分布的表征系统。本文主要研究了用液相外延法在GaAs衬底上生长的InGaAsP/GaAs异质结和用有机金属气相外延法在GaAs上生长的ZnSSe/GaAs异质结两种情况。特别是，我们介绍了一种新的表征半导体异质结界面应力的方法，该方法是我们几年前开发的。该方法利用了三维过渡金属杂质对周围应变场非常敏感的发光特性。利用这种方法，我们研制了一套在Ar离子或Kr离子激光激励下测量半导体异质界面附近的GaAs中与铬有关的发光的新系统，并表征了异质结构界面应力的二维分布。在该系统中，我们引入了一种新的发光测量光学系统。利用该系统，我们研究了InGaP/GaAs和ZnS_xSe_(1-x)Se_(1-x)/GaAs两种半导体异质结，得到了这两种异质结界面应力的分布情况和界面应力的来源。

In this research project, we have investigated the interface stress at some semiconductor heterojunction interfaces and developmed a new characterization sysytem for two-dimensional distribution of the heterointerface stress. Here we have studied mainly two cases of InGaAsP/GaAs heterostructure grown on GaAs substrate by liquid phase epitaxy and ZnSSe/GaAs heterostructure grown on GaAs by organometallic vapor hpase epitaxy. In particular, we have introduced a new characterization method for interface stress at semiconductor heterostructures which was developed by ourselves several years ago. This method utilizes the luminescence due to 3d transition-metal impurities in GaAs crystal which is very sensitive to strain field around the impurities. With the use of this method we have developed a new system shich measures Cr-related luminescence in GaAs near semiconductor heterointerfaces by excitation of Ar- or Kr-ion laser and characterizes two-dimensional distribution of the interface stress at heterostructures. In this system we have introduced a new optics system for the luminescence measurements. Using this system developed in this project, we have investigated two semiconductor heterostructures of InGasP/GaAs and ZnS_xSe_<1-x>/GaAs, and obtained information on the distribution of the interface stress at these heterostructures and the origin of such interface stress.