Department of Electrical Engineering and Computer Sciences, University of California at Berkeley , Berkeley, California 94720, United States.
ACS Nano. 2014 Jul 22;8(7):6833-9. doi: 10.1021/nn501481u. Epub 2014 Jun 5.
Single-crystalline wurtzite InGaAs/InGaP nanopillars directly grown on a lattice-mismatched silicon substrate are demonstrated. The nanopillar growth is in a core-shell manner and gives a sharp, defect-free heterostructure interface. The InGaP shell provides excellent surface passivation effect for InGaAs nanopillars, as attested by 50-times stronger photoluminescence intensities and 5-times greater enhancements in the carrier recombination lifetimes, compared to the unpassivated ones. A record value of 16.8% internal quantum efficiency for InGaAs-based nanopillars was attained with a 50-nm-thick InGaP passivation layer. A room-temperature optically pumped laser was achieved from single, as-grown InGaAs nanopillars on silicon with a record-low threshold. Superior material qualities of these InGaP-passivated InGaAs nanopillars indicate the possibility of realizing high-performance optoelectronic devices for photovoltaics, optical communication, semiconductor nanophotonics, and heterogeneous integration of III-V materials on silicon.
本文展示了在晶格失配的硅衬底上直接生长的单晶纤锌矿结构 InGaAs/InGaP 纳米柱。纳米柱的生长采用核壳方式，形成了无缺陷的异质结构界面。InGaP 壳层为 InGaAs 纳米柱提供了极好的表面钝化效果，与未钝化的纳米柱相比，其光致发光强度增强了 50 倍，载流子复合寿命提高了 5 倍。在 50nm 厚的 InGaP 钝化层的作用下，基于 InGaAs 的纳米柱的内量子效率达到了 16.8%的记录值。通过在硅衬底上生长的单个未掺杂 InGaAs 纳米柱实现了室温光泵浦激光器，其阈值达到了创纪录的低水平。这些经过 InGaP 钝化的 InGaAs 纳米柱具有优异的材料质量，这表明在硅上实现高性能光电设备、光学通信、半导体纳米光子学以及 III-V 材料的异质集成是有可能的。
