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

用原位反射高能电子衍射法研究了沿[001]或[0-11]附近沿[001]或[0-11]方向沿3、5或7度方向生长的ZnSe表面。衍射图表明，1个ML高的原子台阶具有由衬底周围角决定的均匀的阶梯宽度。将观察到的衍射图与模拟的衍射图进行了比较，讨论了原子阶跃结构的均匀性。在50 nm厚、相邻5°的ZnSe表面上，阶梯阵列的阶梯宽度波动小于3ml，阶梯边缘的线性度波动大于60ml。2ml厚的CdSe层的插入没有破坏阶梯状结构。通过原子尺度计算，计算了生长在附近衬底上的ZnSe/CdSe/ZnSe应变单量子阱的势能分布和量子能级。由于电子和重空穴的不均匀应变，在台阶边缘处的CdSe势垒中的势能增加。电导带和价带的电势调制幅度均为22 meV。在势垒层厚度为28ML的GaAs基衬底上生长了ZnSe/(CdSe，ZnSe)/ZnSe单量子阱结构。势垒层由CdSe/ZnSe横向超晶格组成。晶格图像的数字分析表明，CdSe势垒区以均匀的间隔和由衬底周围角度决定的取向嵌入到ZnSe势垒区中。光致发光在平行于台阶边缘的电场作用下呈线性偏振。

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.