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

用反射式高能电子衍射原位研究了GaAs（100）衬底上ZnSe表面向[001]或[0-11]方向3 °、5 °和7 °邻位的生长。衍射图案表明1 ML高度的原子台阶，具有由衬底邻位角确定的均匀平台宽度。将观察到的衍射图样与模拟图样进行了比较，讨论了原子台阶结构的均匀性。在50 nm厚的ZnSe表面上，5°邻位的台阶阵列的台阶宽度的波动小于3 ML，台阶边缘的线性波动大于60 ML。用原子尺度计算方法计算了ZnSe/CdSe/ZnSe应变单量子威尔斯阱GaAs邻位衬底的电势分布和量子能级。由于电子和重空穴的不均匀应变，台阶边缘处的CdSe阱中的势能增加。在GaAs邻位衬底上生长了ZnSe/（CdSe，ZnSe）/ZnSe单量子阱结构，阱层厚度为28 ML。阱层由CdSe/ZnSe横向超晶格组成。晶格图像的数字分析表明，CdSe阱区嵌入在ZnSe势垒区的均匀间隔和在由衬底的邻位角确定的方向。光致发光被发现是线性偏振与电场平行的台阶边缘。

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.