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砷化镓中C_(As)在582cm~(-1)处的局域振动模(LVM)吸收带于低温下存在精细结构,利用其中同位素效应产生的分裂谱线很锐(25K时半高宽小于0.1cm~(-1))的特点,研究了吸收谱线的频率和半高宽以及整个吸收带的积分吸收随温度的变化关系.在GaAs中,C_(As)LVM与晶格带模振动之间的非简谐耦合虽然比离子性较强的晶体中要弱,但在温度变化引起谱线发生频移和半高宽变化时,非简谐效应起了重要的作用.在一些P型和高阻样品中,C_(As)LVM吸收带的积分吸收在低温下随温度降低而反常减小,可用带负电荷的C_(As)受主中心浓度随温度降低而减少来解释,由此获得C_(As)受主消电离情况的信息.
The local vibrational mode (LVM) absorption band of C_ (As) at 582 cm ~ (-1) in gallium arsenide has a fine structure at low temperature, and the splitting spectrum produced by the isotope effect is very sharp (FWHM at 25K Less than 0.1cm ~ (-1)), the frequency and FWHM of the absorption line and the integral absorption of the absorption band with temperature were studied. In GaAs, C_ (As) LVM and lattice mode Although the non-harmonic coupling between vibrations is weaker than the stronger ones, the non-harmonic effect plays an important role in the shift of frequency and the change of FWHM caused by the change of temperature. In some P Type and high-impedance samples, the integral absorption of the C_ (As) LVM absorption band decreases anomalously with the decrease of temperature at low temperature, which can be explained by the decrease of negatively charged C_ (As) acceptor center concentration as the temperature decreases This obtains information of C_ (As) acceptor deionization.