Abstract We performed an intermittent growth of InAs quantum dots (QD) on GaAs(001) at 500 °C. The transition of surface structures during the growth was investigated by using reflection high energy electron diffraction observation. We also performed in situ observation of QD nucleation by using STMBE system in which a scanning tunneling microscope equipped within a molecular beam epitaxy chamber. We have found that the initial QDs formation occurred from 1.15 to 1.38 ML with the intermittent InAs supply. This InAs supply amount was much smaller than that of ordinary continuous deposition ( ∼ 1.66 ML). Moreover, the QDs mainly appeared on the terrace while they mainly appear on step edges by continuous growth at 500 °C. This indicates that the annealing parts of the intermittent growth affected the surface atomic structures of InGaAs wetting layer, uniforming the In fluctuation and stabilized the surface morphology. By the preparation of large ( n × 3 ) and ( 2 × 4 ) area, the QD nucleation occurs with a smaller InAs supply on the surface.

中文翻译：

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GaAs(001) 上 InAs 量子点的间歇生长

摘要 我们在 500 °C 下在 GaAs(001) 上进行了 InAs 量子点 (QD) 的间歇生长。通过反射高能电子衍射观察研究了生长过程中表面结构的转变。我们还通过使用 STMBE 系统对 QD 成核进行了原位观察，其中扫描隧道显微镜配备在分子束外延室中。我们发现初始 QD 形成发生在 1.15 到 1.38 ML 之间，间歇性 InAs 供应。这种 InAs 供应量远小于普通连续沉积的供应量（~1.66 ML）。此外，量子点主要出现在平台上，而它们主要出现在台阶边缘，在 500°C 下连续生长。这表明间歇生长的退火部分影响了 InGaAs 润湿层的表面原子结构，均匀In波动并稳定表面形貌。通过准备大 ( n × 3 ) 和 ( 2 × 4 ) 区域，QD 成核发生在表面上较小的 InAs 供应。