GROWTH OF HIGH-DENSITY ARRAY AND FLUX OF QUQNTUM WIRES B,Y UTILIZING ATOMIC STEPS AND LATTICE STRAIN AND ELECTRON RELAXATION IN THE WIRES

利用原位反射高能电子衍射研究了ZnSe表面在GaAs（100）衬底上向[001]或[0-11]方向生长3,5或7度的情况。衍射图显示原子台阶高度为1 ml，台阶宽度均匀，由衬底邻角决定。将观察到的衍射图与模拟的衍射图进行了比较，讨论了原子阶梯结构的均匀性。台阶阵列在50nm厚的ZnSe 5°表面上，台阶宽度波动小于3ML，台阶边缘线性波动大于60ML。插入2ml厚的CdSe层并没有破坏阶梯-阶地结构。通过原子尺度计算，计算了生长在GaAs邻近衬底上的ZnSe/CdSe/ZnSe应变单量子阱的势分布和量子能级。由于电子和重空穴的应变不均匀，使得台阶边缘的CdSe阱势能增加。导价带电位调制幅值均为22meV。ZnSe/(CdSe,ZnSe)/ZnSe单量子阱结构生长在GaAs邻近衬底上，井层厚度为28 ML，井层由CdSe/ZnSe横向超晶格组成。点阵图像的数字分析表明，CdSe井区以均匀的间隔嵌入在ZnSe势垒区中，其方向由衬底邻角决定。发现电场平行于台阶边缘时，光致发光呈线偏振。

ZnSe surface growing on GaAs(100) substrates vicinal toward [001] or [0-11] by 3, 5 or 7 degree was investigated with in-situ reflection high-energy electron diffraction. Diffraction patterns indicated 1 ML-height atomic steps with uniform terrace widths determined by the substrate vicinal angle. The observed diffraction patterns were compared with simulated patterns to discuss the uniformity of the atomic step structure. The step array on 50nm-thick ZnSe surface with 5° vicinal had a fluctuation less than 3ML in terrace width and a fluctuation longer than 60ML in linearity of step edges. The insertion of a 2ML-thick CdSe layer did not destroy the step-and-terrace structure.The potential profile and quantum energy levels were calculated for ZnSe/CdSe/ZnSe strained single quantum wells grown GaAs vicinal substrates by an atomic scale calculation. Potential energies in the CdSe well at the step edges increased due to inhomogeneous strain for both electron and heavy hole. The amplitude of the potential modulation was 22meV for both conduction and valence bands.ZnSe/(CdSe,ZnSe)/ZnSe single quantum well structures were grown on GaAs vicinal substrates with well-layer thicknesses of 28 ML. The well layer consisted of CdSe/ZnSe lateral superlattices. Digital analysis of lattice image revealed that CdSe well regions were embedded in ZnSe barrier region with a uniform interval and in an orientation determined by the substrate vicinal angle. Photoluminescence was found to be linearly-polarized with electric field parallel to the step edge.