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本文首次报道了在腐蚀图形的（３１１）Ａ衬底上，一种新型三角形点结构的ＭＢＥ生长及其量子阱限制能量的横向变化研究．原子力显微镜三维图象清晰地显示出在原腐蚀凹面图形之间的平面区域，ＭＢＥ选择性生长形成了均匀的三角形收缩结构，其尖角沿［２３３］方向，收缩面由对称的｛１１１｝Ａ面构成．低温阴极荧光谱和图象测试研究结果表明：这种点状外延结构存在三个分离的荧光发射区域，分别对应于三个不同的激发光波长．说明这种点结构中量子阱层厚度的变化引入了量子阱限制能量的横向变化．低温微区光致发光谱测试得到高度可分辨的三个发光峰，结果说明在围绕点状结构顶部区域形成了１３ｍｅＶ横向势垒，且具有较高的辐射复合发光效率．
This paper reports for the first time the MBE growth of a new triangular point structure and the lateral variation of its quantum well confinement energy on a (311) A substrate with an etched pattern. The three-dimensional image of the AFM clearly shows that in the plane area between the original etched concave patterns, the MBE selectively grows to form a uniform triangular contracted structure with the sharp corners along the [233] direction and the contracted surface by the symmetrical {111} A surface constitute. The results of cryogenic cathodic fluorescence spectroscopy and image test show that there are three separate fluorescence emission regions in this dotted epitaxial structure, which correspond to three different excitation light wavelengths respectively. It shows that the variation of the quantum well layer thickness in this point structure introduces the quantum well to limit the lateral variation of energy. Low temperature micro-photoluminescence (PLGA) spectroscopy results in three highly resolved luminescence peaks. The results show that a 13meV lateral barrier is formed around the top of the punctiform structure and has high radiative recombination efficiency.