Department of Electrical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, 790-784, Republic of Korea.
Small. 2014 Sep 24;10(18):3795-802. doi: 10.1002/smll.201400373. Epub 2014 May 15.
The photoresponse characteristics of In2Se3 nanowire photodetectors with the κ-phase and α-phase structures are investigated. The as-grown κ-phase In2Se3 nanowires by the vapor-liquid-solid technique are phase-transformed to the α-phase nanowires by thermal annealing. The photoresponse performances of the κ-phase and α-phase In2Se3 nanowire photodetectors are characterized over a wide range of wavelengths (300-900 nm). The phase of the nanowires is analyzed using a high-resolution transmission microscopy equipped with energy dispersive X-ray spectroscopy and X-ray diffraction. The electrical conductivity and photoresponse characteristics are significantly enhanced in the α-phase due to smaller bandgap structure compared to the κ-phase nanowires. The spectral responsivities of the α-phase devices are 200 times larger than those of the κ-phase devices. The superior performance of the thermally phase-transformed In2Se3 nanowire devices offers an avenue to develop highly sensitive photodetector applications.
研究了具有κ相和α相结构的 In2Se3 纳米线光电探测器的光电响应特性。通过汽-液-固技术生长的未处理κ相 In2Se3 纳米线通过热退火转变为α相纳米线。在较宽的波长范围内（300-900nm），对κ相和α相 In2Se3 纳米线光电探测器的光电响应性能进行了表征。使用配备有能量色散 X 射线光谱仪和 X 射线衍射仪的高分辨率透射显微镜分析了纳米线的相。与κ相纳米线相比，由于较小的能带结构，α相的电导率和光电响应特性得到了显著提高。α相器件的光谱响应率比κ相器件高 200 倍。热相变 In2Se3 纳米线器件的优异性能为开发高灵敏度光电探测器应用提供了途径。
