本研究使用濺鍍機鍍製三種製成參數之氧化銦鉭薄膜,其三種製成分別為氧化鉭5奈米氧化銦7奈米疊層(5-7奈米)、氧化鉭10奈米氧化銦14奈米疊層(10-14奈米)以及雙鈀共鍍,鍍膜完後薄膜以不同溫度條件快速退火爐,希望藉由熱處理方式改善其微結構,讓薄膜可以發揮光觸媒效果。薄膜製程結束後,我們使用X光繞射儀(XRD)及能量散佈分析儀(EDS)發現在5-7奈米及10-14奈米製程之薄膜中出現氧化銦鉭之結晶相,然而共鍍製程之薄膜中並沒有出現其結晶相。文獻指出結晶氧化銦鉭可以在紫外光及可見光照射下發揮光觸媒效果,這裡我們著重於測試快速退火過後之薄膜在可見光照下其在水中分解亞甲基藍的光降解能力,其5-7奈米及10-14奈米製程之薄膜在六小時可見光照射下可以達到45%之光降解效率。使用分光光譜儀(UV-Vis-NIR)結果可以計算出薄膜之能隙大小,並且會根據計算結果討論其光觸媒效果機制,其與異質連接半導體之電子電洞分離機制相似。;Indium tantalum oxide thin film was deposited by sputtering using three different designs: 5-7 and 10-14 nm alternative layers of In2O3 and Ta2O5, and co-sputtering of In2O3 and Ta2O5. Then as-deposited films were rapid annealed at different temperatures to assess the thermal effects on microstructures and photocatalytic functions. Results from XRD and EDS indicates that crystalline InTaO4 emerges in 5-7 and 10-14 nm stacks of films but absent in the co-sputtered films. Since crystalline InTaO4 is capable of photocatalysis under both ultraviolet and visible light, we particularly tested the annealed films in water to degrade methylene blue under visible light. The photo-induced degradation on methylene blue by 5-7 and 10-14 nm stacks can reach 45% after 6-hour continuous exposure. Using UV-Visible-NIR spectroscopy, we can estimate the optical band gaps in these annealed films and from these estimations, a mechanism for the photocatalysis is discussed following. This mechanism is similar to other electron-hole separation and transfer across the heterogeneous junctions in semiconductors.