利用时域有限差分法对不同材料和厚度衬底上矩形孔金属结构太赫兹（THz）波的透射特性进行了数值分析。研究表明：矩形孔金属阵列对THz光谱具有频率选择特性，这为太赫兹滤波功能器件的开发提供了基础。在实际应用中，这种金属微结构常常需要制备在某种衬底上，而衬底材料及厚度无疑会对其太赫兹透射特性带来影响。研究了不同衬底材料和衬底厚度的矩形孔金属结构太赫兹透射性质，通过数值模拟研究发现，对于同一种衬底材料，随着衬底厚度的增加，矩形孔金属结构的透射峰峰位向低频移动。比较高阻硅和聚四氟乙烯两种衬底材料发现，高介电常数的硅衬底引起的透射峰移动更为明显。

The terahertz transmission characteristics of the rectangular-hole metal structure on different materials and thicknesses of substrates are studied based on the finite difference time domain method. The results show that there exists the frequency selectivity in THz transmission spectrum of the rectangular-hole metallic structure. The frequency selectivity provides the basis of the terahertz filter. In practical applications, these metallic microstructures often need to be deposited on the substrates. Obviously, the substrate material and its thicknesses have influence on the terahertz transmission characteristics of metallic microstructures. We investigate how the different substrate materials and its thicknesses affect the terahertz transmission of entire structure. By numerical simulation, it is found that the transmission peak shifts into the lower frequency with increasing of the substrate thicknesses. Comparing Si and polytetrafluoroethylene (PTFE) as the substrate materials, it is shown that peak shift of Si substrates with high dielectric constant is more obvious.