干涉-吸收型太阳光谱选择性吸收表面

Solar Spectrally Selective Absorbing Surfaces by Interference and Absorption

基于等效媒质理论，用透反法确定了单靶溅射沉积的铝－氮复合膜的填充因子，并研究了不同填充因子复合膜以及由两层不同填充因子复合膜构成的干涉－吸收型选择性吸收涂层的热处理性能。结果表明，合理地选取复合膜的填充因子及厚度，可使刚沉积及经在真空中400℃，500℃保温1h热处理后的膜系的太阳吸收比α（AM2）＞0．94。80℃的法向发射比εn约0．04．α／εn＞20。

Al-AlN composite films were deposited by magnetron sputtering tectnology with single Al target. The metal volume fractions of the composites were determined by comparing the measured reflectance and transmittance spectra with the calculations on the basis of effective medium theory. Heat treatments of the selective surfaces were studied in vacuum for graded composites with various metal voLume fractions,and the surface was made up of two layers of composited associated with two metal volume fractions. The selective surface incorporating the two composite layers on Al base layer exhibits the interference peaks in the reflectance spectrum. The selective surface with AlN and Al2O3, antirefection layers has solar absorptance a(AM2) about 0.94 for heat-treated 1 hr at 400℃ in vacuum and normal emittance εn(80℃) about 0.04,the ratio of α/εn is more than 20.