摘要：采用太赫兹时域光谱装置测试SiC和Si₃N₄粉体在0.4～2.4 THz的透射光谱,研究SiC和Si₃N₄粉体对太赫兹波的吸收性能与其电导率的关系,分析SiC和Si₃N₄粉体对太赫兹波的散射特性。结果表明,SiC是一种半导体材料,其内部含有较多可以自由移动的载流子,对太赫兹波的吸收较强;Si₃N₄是绝缘性很好的材料,对太赫兹波的吸收很小;SiC和Si₃N₄粉体对太赫兹波的散射作用属于瑞利散射,但是测试波长比粉体粒径大得多,散射效果不明显。

关键词：太赫兹波；太赫兹时域光谱；吸收；电导率；散射

Abstract：Transmission spectra of SiC and Si₃N₄powders in 0.42.4 THz were measured using terahertz time-domain spectroscopy.The relationship between the terahertz waves absorption performance and the conductivity of SiC and Si₃N₄ powders was studied.The terahertz waves scattering characteristics of SiC and Si₃N₄ powders were analyzed.The results indicate that the terahertz waves absorption performance of SiC powders is higher than that of Si₃N₄powders,because SiC is a kind of semiconductor materials in which there are much more free carriers than Si₃N₄.The terahertz waves scattering of SiC and Si₃N₄ powders belongs to Rayleigh scattering.But the scattering effect is not obvious because of the big gap between the wavelength of terahertz waves and the particle sizes of SiC and Si₃N₄powders.

Keywords：terahertz wave;terahertz time-domain spectroscopy;absorption;conductivity;scattering