Networks of vertically c-oriented prism shaped InN nanowalls, are grown on c-GaN/sapphire templates using a CVD technique, where pure indium and ammonia are used as metal and nitrogen precursors. A systematic study of the growth, structural and electronic properties of these samples shows a preferential growth of the islands along [11-20] and [0001] directions leading to the formation of such a network structure, where the vertically [0001] oriented tapered walls are laterally align along one of the three [11-20] directions. Inclined facets of these walls are identified as r-planes [(1-102)-planes] of wurtzite InN. Onset of absorption for these samples is observed to be higher than the band gap of InN suggesting a high background carrier concentration in this material. Study of the valence band edge through XPS indicates the formation of positive depletion regions below the r-plane side facets of the walls. This is in contrast with the observation for c-plane InN epilayers, where electron accumulation is often reported below the top surface.

中文翻译：

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通过化学气相沉积技术在 c-GaN/蓝宝石模板上生长的垂直 c 取向棱柱 InN 纳米壁网络

使用 CVD 技术在 c-GaN/蓝宝石模板上生长垂直 c 取向棱柱形 InN 纳米壁网络，其中纯铟和氨用作金属和氮前体。对这些样品的生长、结构和电子特性的系统研究表明，岛沿 [11-20] 和 [0001] 方向优先生长，导致形成这种网络结构，其中垂直 [0001] 方向逐渐变细壁沿三个 [11-20] 方向之一横向对齐。这些壁的倾斜面被识别为纤锌矿 InN 的 r 面 [(1-102) 面]。观察到这些样品的吸收开始高于 InN 的带隙，表明该材料中具有高背景载流子浓度。通过 XPS 对价带边缘的研究表明在壁的 r 平面侧面下方形成了正耗尽区。这与 c 面 InN 外延层的观察结果形成对比，其中电子积累通常报告在顶面下方。