Nanotechnology. 2008 Jun 18;19(24):245304. doi: 10.1088/0957-4484/19/24/245304. Epub 2008 May 9.
The transformation of InAs islands to quantum rings (QRs) by metalorganic vapor phase epitaxy is investigated. After covering the InAs islands with a thin GaAs partial capping layer and annealing under tertiarybutylarsine (TBAs) flow, ring-shaped nanostructures with a density of 10(7)-10(9) cm(-2) are obtained at 500-600 °C. The effects of the growth temperature, annealing process and thickness of the partial capping layer are studied. Optimum values for the annealing time and the partial capping layer thickness were found to be 60-120 s and 0.5-2.0 nm, respectively. Low temperature photoluminescence (PL) emission peaks from islands and QRs grown at 500 °C are observed at 1.04 eV and 1.22 eV, respectively. The annealing temperature affected the QR evolution and the PL emission from the QRs due to the temperature dependence of the diffusion rate of indium atoms.
采用金属有机气相外延法将 InAs 岛转化为量子环 (QR)。在将 InAs 岛覆盖一层薄的 GaAs 部分覆盖层并在三丁基砷 (TBAs) 流下退火之后，在 500-600°C 下获得了密度为 10(7)-10(9)cm(-2)的环形纳米结构。研究了生长温度、退火过程和部分覆盖层厚度的影响。发现退火时间和部分覆盖层厚度的最佳值分别为 60-120 s 和 0.5-2.0 nm。在 500°C 下生长的岛和 QR 的低温光致发光 (PL) 发射峰分别在 1.04 eV 和 1.22 eV 处观察到。由于铟原子扩散率随温度的变化，退火温度会影响 QR 的演化和 QR 的 PL 发射。
