Mattila M, Hakkarainen T, Mulot M, Lipsanen H
Optoelectronics Laboratory, Helsinki University of Technology, PO BOX 3500, FIN-02015 HUT, Finland.
Nanotechnology. 2006 Mar 28;17(6):1580-3. doi: 10.1088/0957-4484/17/6/008. Epub 2006 Feb 21.
The formation and photoluminescence (PL) of InP nanowires grown by metal organic vapour phase epitaxy on InP(111)B substrates, using colloidal gold nanoparticles as catalysts, are investigated. The dependence of the orientation and dimensions of the nanowires on the growth temperature is studied using scanning electron microscopy. Vertically aligned [Formula: see text] oriented nanowires with a mean base diameter in the range 50-150 nm, and a tip diameter of 50 nm, show a PL blue-shift of about 80 meV compared to the substrate. Blue-shift due to quantum confinement is ruled out because of the large diameter of the nanowires. A clear correlation between the orientation of the nanowires on the substrate and the PL peak position is observed. Based on x-ray diffraction and transmission electron microscopy measurements, it is proposed that the as-grown vertically oriented nanowires have crystallized in the wurtzite lattice instead of in the zinc-blende structure, which results in a blue-shifted PL.
研究了以胶体金纳米颗粒为催化剂，通过金属有机气相外延在InP(111)B衬底上生长的InP纳米线的形成及其光致发光(PL)特性。利用扫描电子显微镜研究了纳米线的取向和尺寸对生长温度的依赖性。垂直排列的[化学式：见原文]取向纳米线，平均基部直径在50 - 150纳米范围内，尖端直径为50纳米，与衬底相比，其PL蓝移约80毫电子伏特。由于纳米线直径较大，排除了量子限制导致蓝移的可能性。观察到纳米线在衬底上的取向与PL峰位置之间存在明显的相关性。基于X射线衍射和透射电子显微镜测量结果，提出生长的垂直取向纳米线结晶为纤锌矿晶格而非闪锌矿结构，这导致了PL蓝移。
