Infrared characterization of GaN and GaN/AlGaN molecular beam epitaxial layers
Infrared characterization of GaN and GaN/AlGaN molecular beam epitaxial layers
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DOI：
10.1116/1.582241
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发表时间：
2000-03
期刊：
影响因子：
--
通讯作者：
J. Bardwell;M. Dharma-wardana;H. Tang;J. Webb
中科院分区：
文献类型：
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作者：
J. Bardwell;M. Dharma-wardana;H. Tang;J. Webb
发展了一种用于GaN和GaN/AlGaN外延层和多层膜表征的红外反射技术。红外光通过KRS-5内反射晶体被带到III族氮化物表面。该技术是互补的拉曼测量，并提供信息的纵向和横向光学（LO）模式的GaN和AlN。对于薄的GaN层，薄的，22 nm厚的AlN成核层的模式可以清楚地观察到的光谱。GaN的自由载流子浓度可以通过分析掺杂样品中存在的LO声子-等离子体激元耦合模式来表征。由于光在GaN层中被多次反射，因此该技术可以潜在地检测GaN中的杂质（例如H或C）。应用此技术来表征高品质的分子束外延层进行了讨论。
An infrared reflection technique has been developed for the characterization of GaN and GaN/AlGaN epitaxial layers and multilayers. The infrared light is brought to the III-nitride surface with a KRS-5 internal reflection crystal. The technique is complimentary to Raman measurements and provides information on the longitudinal and transverse optical (LO) modes of GaN and AlN. For thin GaN layers, the modes of the thin, 22-nm-thick AlN nucleation layer can be clearly observed in the spectra. The free carrier concentration of the GaN can be characterized by analyzing the LO phonon-plasmon coupled mode present in doped samples. Because the light is multiply reflected in the GaN layer, the technique can potentially detect impurities (such as H or C) in the GaN. The application of this technique to characterize high quality molecular beam epitaxial layers is discussed.