Growth and Characterization of High-Quality, Relaxed InyGa1−yN Templates for Optoelectronic Applications
Growth and Characterization of High-Quality, Relaxed InyGa1−yN Templates for Optoelectronic Applications
复制标题
用于光电应用的高质量、宽松的 InyGa1−yN 模板的生长和表征
DOI：
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发表时间：
2015
影响因子：
2.1
通讯作者：
S. Bedair
中科院分区：
文献类型：
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作者：
D. Van Den Broeck;D. Bharrat;Z. Liu;N. El;S. Bedair
厚的高质量InGaN层可用作发光二极管中量子阱应变减小的模板以及太阳能电池结构中的光吸收层。然而，目前的InGaN生长技术主要受限于V-坑形成和不均匀的铟组成。我们报告了厚的应变弛豫InyGa 1 −yN层的生长和表征，其中0.08 ≤ y ≤ 0.11，通过金属有机化学气相沉积使用半体方法，包括周期性地将2 nm GaN夹层插入体InyGa 1 −yN结构中;然后在1000°C下进行尖峰退火。光致发光、X射线衍射、扫描电子和原子力显微镜显示，半块体InyGa 1-yN的光学和电学性能优于相同温度下生长的传统块体InyGa 1-yN的光学和电学性能，上级。半块体InyGa 1 −yN薄膜的铟含量均匀，V型坑密度显著降低，即使在临界层厚度以上生长也是如此。双晶X射线衍射摇摆曲线也揭示了半块体InyGa 1 −yN薄膜中的螺位错密度与块体InyGa 1 − yN薄膜相比降低了一个数量级。
Thick, high-quality InGaN layers can be used as templates for quantum well strain reduction in light-emitting diodes and as optical absorption layers in solar cell structures. Current InGaN growth technology, however, is primarily limited by V-pit formation and non-uniform indium composition. We report the growth and characterization of thick, strain-relaxed InyGa1−yN layers, with 0.08 ≤ y ≤ 0.11, by metal organic chemical vapor deposition using the semibulk approach, which consists in periodic insertion of 2-nm GaN interlayers into the bulk InyGa1−yN structure; these are then spike-annealed at 1000°C. Photoluminescence, x-ray diffraction, and scanning electron and atomic force microscopy revealed that the semibulk InyGa1−yN had optical and electrical properties superior to those of conventional bulk InyGa1−yN grown at the same temperature. Homogeneous indium content and substantial reduction of V-pit density were observed for the semibulk InyGa1−yN films, even when grown above the critical layer thickness. Double-crystal x-ray diffraction rocking curves also revealed a one order of magnitude reduction of screw dislocation density in the semibulk InyGa1−yN film compared with the bulk InyGa1−yN film.