【摘要】 利用ＭＢＥ方法在（００１）衬底上成功地生长了密度大、尺寸小、发红光的ＩｎＡｌＡｓ／Ａｌ－ＧａＡｓ 量子点结构． 通过原子力显微镜观测表明， ＩｎＡｌＡｓ量子点的密度和大小都随覆盖厚度的增加而增大； 发现Ａｌ原子的表面迁移率决定ＩｎＡｌＡｓ 量子点的形貌． 光荧光谱证实了量子点的发光峰值在红光范围， 并结合形貌的统计得到了量子点的发光峰展宽主要是受量子点的横向尺寸影响．更多还原

【Abstract】 The effect of InAlAs deposition thickness on the areal density, size, uniformity and spatial distribution of self organized In 0.65 Al 0.35 As/Al 0 5 Ga 0 5 As quantum dots was studied, grown on (001) GaAs substrate by molecular beam epitaxy (MBE). The progression of surface morphology of In 0.65 Al 0.35 As quantum dots is investigated in detail by atomic force microscopy (AFM). A high density, small size, red emission self organized In 0.65 Al 0.35 As quantum dots have been obtained. The self organized In 0.65 Al 0.35 As quantum dots density and average size are found to increase with increasing the InAlAs deposition thickness. Moreover, the increase of dots density is slow, compared with the variance of InAs/GaAs quantum dots with InAs deposition thickness, this might be beneficial for the realization of low threshold quantum dot lasers since both quantum confinement and gain region are increased. It was found that the surface diffusion of Al atoms is an important factor in determining the structural properties of In 0.65 Al 0.35 As quantum dots. We believe that the Al atom of the smaller surface migration range plays a large role in determining In 0.65 Al 0.35 As quantum dots nucleation sites. The low temperature photoluminescence (PL) from the recombination of carriers in the buried In 0.65 Al 0.35 As/Al 0.5 Ga 0.5 As quantum dots is observed 1.701eV energy position, its linewidth is determined principally by the lateral size of dots through investigating the distribution of dots size.更多还原