Reduction of the dislocation density in HVPE-grown GaN epi-layers by an in situ SiNx treatment
Reduction of the dislocation density in HVPE-grown GaN epi-layers by an in situ SiNx treatment
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DOI：
10.1016/j.jcrysgro.2009.11.043
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发表时间：
2010-02-01
影响因子：
1.8
通讯作者：
Hageman, P. R.
中科院分区：
文献类型：
--
作者：
Ashraf, H.;Rao, D. V. Sridhara;Hageman, P. R.
一种新方法可以降低氢化物气相外延 (HVPE) 生长的 GaN 外延层中的位错密度。通过这种最先进的质量方法，在 HVPE 工艺中对 SiNx 进行原位处理，在蓝宝石衬底上生长 GaN 层。结果发现，在沉积成核层（NL）之后引入原位处理最有效。通过扫描电子显微镜 (SEM) 分析证实，非晶 SiNx 用作掩模，仅允许选择性生长 GaN 种子，因此位错密度降低（低至 106 cm(-2)），与标准样品（未经 SiNx 处理生长）相比，降低了一个数量级。透射电子显微镜 (TEM) 研究表明，具有混合（螺旋和边缘分量）特征的位错大多穿入 GaN 层。低温光致发光表明，在 SiN 的最佳位置生长的层具有良好的光学质量。治疗。 (C) 2009 Elsevier B.V. 保留所有权利。
A new method has been approached to reduce the dislocation density in hydride vapor phase epitaxy (HVPE)-grown GaN epi-layers. By this method, state of the art quality, GaN layers were grown on sapphire substrates with an in situ treatment of SiNx in HVPE process. It was found out that the in situ treatment worked most effectively when introduced after the deposition of the nucleation layer (NL). Amorphous SiNx, served as a mask allowing only selective growth of GaN seeds as confirmed by scanning electron microscopy (SEM) analysis and thus a reduction of the dislocation density (down to 106 cm(-2)) With one order of magnitude lower compared to the standard samples (grown without the SiNx treatment) was obtained. Transmission electron microscopy (TEM) studies revealed that dislocations with a mixed (both screw and edge component) character mostly thread into the GaN layer. Low-temperature photoluminescence showed good optical quality of the layers grown with optimal position of SiN. treatment. (C) 2009 Elsevier B.V. All rights reserved.