本研究選用了三氧化二鋁以及鎢材料做為半透明介電質與金屬干涉疊層型之主要研究，利用多層膜的結構來增加對太陽能譜的選擇性吸收，並且能在高溫時有低的放射率。首先利用套裝軟體COMSOL Multiphysics 建構數學模式，使用有限元素法(FEM)來模擬太陽能吸收層的傳播特性並求得其吸收、反射及穿透曲線，透過參數分析取得最佳平均吸收率之薄膜結構尺度，以便做為實驗參考依據。接著使用拋光過的SUS 304不鏽鋼基板，並以鎢材料做為金屬反射層，使用磁控濺鍍機將試片完整製作出而得到良好的選擇性吸收膜，並與模擬結果作比對。

The present research is aimed to develop a high-temperature solar selective absorber based on multi-layer structure. This multi-layer selective solar absorber consists of dielectric and metallic layers serving as the absorbing layer as well as an IR reflector layer coated on SUS 304 substrate. Aluminium oxide is chosen to be the dielectric layer, and tungsten is chosen to be the metallic layer. By having this multi-layer structure, both solar absorptance and emittance can be improved significantly especially under high temperature. In parallel, numerical simulation is also performed by using a commercial software, COMSOL Multiphysics, in which a FEM analysis of the absorptance, reflectivity and transmittance of the coating is carried out. Based on the simulation results, theoretical values of surface properties under a variety of combinations of the thicknesses of the layers can be obtained. The aluminium oxide and tungsten are then fabricated on the stainless steel substrate by using sputtering process in accordance with the optimal thicknesses predicted by the simulation. The real values of solar absorptance and thermal emittance are measured and compared with the simulation results.

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