High-resolution X-ray diffraction analysis on HVPE-grown thick GaN layers
High-resolution X-ray diffraction analysis on HVPE-grown thick GaN layers
复制标题
HVPE 生长的厚 GaN 层的高分辨率 X 射线衍射分析
DOI：
10.1016/j.jcrysgro.2009.01.050
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发表时间：
2009-05-01
影响因子：
1.8
通讯作者：
Yang, H.
中科院分区：
文献类型：
--
作者：
Liu, J. Q.;Wang, J. F.;Yang, H.
采用高分辨X射线衍射（HR-XRD）方法测量了氢化物气相外延（HVPE）生长的GaN厚层的穿透位错密度。比较了镶嵌模型、Kaganer模型和改进的Kaganer模型。记录（0 0 0 2）、（1 0（1）在棒5上）、（1 0（1）在棒4上）、（1 0（1）在棒3上）、（1 0（1）在棒2上）、（1 0（1）在棒1上）和（1 0（1）在棒0上）平面的X射线摇摆曲线（XRC）用于定量分析。螺旋，刃，和混合型螺纹位错密度进行了模拟，从XRD线轮廓，通过使用三个模型。用原子力显微镜（AFM）、湿化学腐蚀和阴极发光（CL）等方法测量了位错密度。结果表明，与镶嵌模型相比，Kaganer模型具有更高的物理精度，能够很好地解释HVPE生长的高质量GaN的摇摆曲线展宽现象。假设一个随机分布的螺纹位错配置，我们修改了Kaganer模型。基于修正的Kaganer模型，分析了HVPE生长GaN厚膜中刃型和螺型位错密度的变化规律，厚度范围从20 μ m到700 μ m。结果表明，随着膜厚的增加，螺旋型位错密度比刃型位错密度下降得更快。(C)2009 Elsevier B. V.保留所有权利。
The threading dislocation density of hydride vapor phase epitaxy (HVPE)-grown thick GaN layers was measured by high-resolution X-ray diffraction (HR-XRD). Three models were compared, namely mosaic model, Kaganer model and modified Kaganer model. X-ray rocking curves (XRC) of (0 0 0 2), (1 0 (1) over bar 5), (1 0 (1) over bar 4), (1 0 (1) over bar 3),(1 0 (1) over bar 2), (1 0 (1) over bar 1) and (1 0 (1) over bar 0) planes were recorded for quantitative analysis. The screw-, edge-, and mixed-type threading dislocation densities were simulated from the XRD line profile by using the three models. The dislocation density was also measured by atomic force microscopy (AFM), wet chemical etching and cathodoluminescence (CL). The results showed that the Kaganer model was more physically precise and well explained the rocking curve broadening for HVPE-grown high-quality GaN compared with the mosaic model. Assuming a randomly distributed threading dislocation configuration, we modified the Kaganer model. Based on the modified Kaganer model, the edge and screw threading dislocation densities in HVPE-grown GaN thick films ranging from 20 Pm up to 700 mu m were analyzed. It was shown that screw-type dislocation density decreased more rapidly than edge-type dislocation with increase in film thickness. (C) 2009 Elsevier B.V. All rights reserved.