Ge/ZnS 一维光子晶体的设计、制备及低红外发射率性能∗

摘要

Ge/ZnS one-dimensional photonic crystal (1DPC)with low infrared emissivity at the wavelength of 8-14 μm was designed according to the systematically theoretical analysis of the influencing factors of dielectric layer thickness,refractive index difference of different dielectric materials,and the number of periods.Then the 1DPC was successfully prepared by alternating thin films of Ge and ZnS on the quartz substrate by using the optical coating tech-nology.The microstructure and spectral emissivity of as-prepared 1DPC were characterized by using scanning electron microscope (SEM)and Fourier transform infrared spectrometer (FTIR),respectively.The results show that the as-prepared 1DPC has low infrared emissivity at the wavelength of 8 - 14 μm,the average emissivity can be as low as 0.1 95.Using inorganic semiconductor materials such as Ge and ZnS through rational design of 1DPC can also get the low infrared emissivity which is lower than 0.2.%通过从理论上分析介质层厚度、不同介质材料的折射率差及周期数对一维光子晶体红外发射率的影响规律，设计得到了可实现8~14μm 波段低红外发射率性能的 Ge/ZnS 一维光子晶体。随后采用光学镀膜技术在石英基片上通过交替沉积 Ge 层和 ZnS 层的方法制得所设计的一维光子晶体，并采用扫描电镜(SEM)及傅里叶变换红外光谱(FTIR)分别对其微结构及光谱发射率进行了系统研究。结果表明，所制备一维光子晶体在8~14μm 波段具有低红外发射率性能，其平均发射率可低至0.195。采用 Ge、ZnS 等无机半导体材料，通过合理的一维光子晶体设计同样可以获得低至0.2以下的红外发射率。