Technische Physik, Physikalisches Institut and Wilhelm Conrad Röntgen Research Center for Complex Material Systems, Universität Würzburg, Würzburg, Germany.
Nanotechnology. 2012 Sep 21;23(37):375301. doi: 10.1088/0957-4484/23/37/375301. Epub 2012 Aug 24.
A technology platform for the epitaxial growth of site-controlled InP quantum dots (QDs) on GaAs substrates is presented. Nanoholes are patterned in a GaInP layer on a GaAs substrate by electron beam lithography and dry chemical etching, serving as QD nucleation centers. The effects of a thermal treatment on the structured surfaces for deoxidation are investigated in detail. By regrowth on these surfaces, accurate QD positioning is obtained for square array arrangements with lattice periods of 1.25 μm along with a high suppression of interstitial island formation. The optical properties of these red-emitting QDs (λ ~ 670 nm) are investigated by means of ensemble- and micro-photoluminescence spectroscopy at cryogenic temperatures.
介绍了一种在 GaAs 衬底上外延生长位控 InP 量子点 (QD) 的技术平台。通过电子束光刻和干法化学蚀刻在 GaAs 衬底上的 GaInP 层中形成纳米孔，作为 QD 的成核中心。详细研究了热退火处理对结构化表面脱氧的影响。通过在这些表面上再生长，可以获得晶格周期为 1.25 μm 的正方形阵列排列的精确 QD 定位，同时 interstitial island 的形成得到了很好的抑制。通过低温下的集总-微光致发光光谱研究了这些发红光的 QD（λ~670nm）的光学性质。
