Nakashima Shin-ichi, Okumura Hazime, Yamamoto Taketsugu, Shimidzu Ryosuke
National Institute of Advanced Science and Industrial Technology, Central 2, Umezono 1-1-1, Tsukuba, Ibaraki 305-8568 Japan.
Appl Spectrosc. 2004 Feb;58(2):224-9. doi: 10.1366/000370204322842977.
We have developed a high-throughput deep-ultraviolet (DUV) Raman microspectrometer with excitation from a continuous wave (cw) laser operated at 244 nm that enables us to characterize thin surface layers of wide-gap semiconductors. This spectrometer system consists of a filter spectrometer for the rejection of stray light and a high-dispersion spectrograph combined with a liquid nitrogen cooled charge-coupled device (CCD) detector and extends the low-frequency limit of the observable spectral range down to 170 cm(-1). In the microscope we use a Cassegrain reflective objective for the collection of the scattered light and an off-axis mirror for introduction of the excitation laser light. DUV Raman spectroscopy has been applied for studying wide-gap semiconductors including SiC and AlGaN epitaxial films and shallow implanted layers of these materials. Raman spectra of various crystals have also been measured for examining the performance of this system. Resonance enhancement of Raman bands has been observed for several semiconductors, and the results are discussed.
我们开发了一种高通量深紫外（DUV）拉曼光谱仪，其激发源为波长244 nm的连续波（cw）激光器，该光谱仪能够对宽禁带半导体的薄表面层进行表征。该光谱仪系统由用于滤除杂散光的滤光光谱仪和与液氮冷却电荷耦合器件（CCD）探测器相结合的高色散光谱仪组成，可将可观测光谱范围的低频极限扩展至170 cm-1。在显微镜中，我们使用卡塞格伦反射物镜收集散射光，并使用离轴镜引入激发激光。DUV拉曼光谱已被用于研究包括SiC和AlGaN外延膜以及这些材料的浅注入层在内的宽禁带半导体。还测量了各种晶体的拉曼光谱以检验该系统的性能。已观察到几种半导体的拉曼谱带的共振增强，并对结果进行了讨论。
