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利用二次离子质谱（ＳＩＭＳ）系统地研究了生长温度，Ａｌ组份ｘ值和Ａｓ＿４压强对Ｓｉδ掺杂Ａｌ＿ｘＧａ＿（１－ｘ）Ａｓ的ＳＩＭＳ深度剖面，Ｓｉ原子表面分凝和向衬底扩散的影响。实验发现，在外延生长Ｓｉδ掺杂Ａｌ＿ｘＧａ＿（１－ｘ）Ａｓ时，随着生长温度的提高或Ａｌ组份Ｘ值增加，Ｓｉ掺杂分布ＳＩＭＳ峰都非对称展宽，表面分凝作用加强，但不影响Ｓｉ原子的扩散，因此ＳＩＭＳ剖面的展宽与扩散无关。另外，我们还发现Ａｓ＿４压强高于１．５×１０￣（－５）ｍｂａｒ时，Ａｓ＿４压强对δ掺杂空间分布影响不大，而Ａｓ＿４压强低于此压强时，Ｓｉ掺杂分布峰宽度增加很快，这主要由杂质扩散作用引起。生长温度对掺杂分布峰影响最大，其次是Ａｌ组份影响，而较小Ａｓ＿４压强的影响不可忽视。这些研究结果对外延生长Ｓｉδ掺杂Ａｌ＿ｘＧａ＿（１－ｘ）Ａｓ材料是有价值的。
SIMS was used to systematically study the SIMS depth profiles of Si δ-doped Al x Ga 1-x As As, the segregation of Si atoms and the diffusion to the substrate influences. The experimental results show that SIMS peaks of Si doping distribution are broadened asymmetrically and surface segregation is strengthened with the increase of growth temperature or the increase of X value of Al composition during the epitaxial growth of Si 6 -doped Al x Ga 1-x As As Does not affect the diffusion of Si atoms, so the SIMS profile broadening and diffusion have nothing to do. In addition, we also found that when As_4 pressure is higher than 1.5 × 10 ~ (-5) mbar, As_4 pressure has little effect on δ doping spatial distribution, while As_4 pressure is lower than this pressure, the peak width of Si doping distribution increases Quickly, this is mainly caused by the diffusion of impurities. The growth temperature has the strongest influence on the doping peak, followed by the influence of Al composition, but the effect of smaller As_4 pressure can not be neglected. These findings are valuable for the epitaxial growth of Si 6 -doped Al x Ga 1-x As materials.