隨著製程技術的提昇積體電路(IC)之元件密度亦大幅度的增加，而與元件效能及可靠度(Reliability)息息相關的散熱問題則成為一極重要的課題。近年來熱電冷凍(Thermoelectric refrigeration)具有易微型化與高可靠度之優點，因此逐漸受到學界與產業界的矚目，而熱電冷凍之效能與熱電材料之熱電優質(ZT值)有極密切之關係，Bi2Te3化合物半導體是目前室溫下所知最佳之熱電材料。本研究係利用磁控濺鍍法(Sputtering)來製備Bi2Te3化合物半導體薄膜，將Bi/Te雙層複合薄膜依序鍍在長有氧化層之矽基材上，並利用高溫熱處理的方法，藉由固態擴散反應生成Bi-Te化合物薄膜，探討Bi及Te薄膜厚度比對於Bi-Te化合物之成份比、電性及熱電性質之影響。研究結果顯示Bi-Te複合薄膜經熱處理(200℃，24小時)後，Seebeck係數由-38.3 μV/K增加至-201.3 μV/K，電阻率由2.02□10-3 μΩ-cm微幅增加到2.33□10-3 μΩ-cm，而熱導係數則由2.56 W/m□K降至0.71 W/m□K，可得到室溫下(T=300K)最大熱電優值ZT值為0.735。此外利用XRD分析薄膜微結構及其成份，並透過SEM來觀察薄膜表面微結構與兩層薄膜間互相擴散之情形。

With the evolution of VLSI process technology, component density of Integrated circuit(IC) increased significantly and heat dissipation is becoming a very important issue for device performance and IC reliability consideration. Due to the advantages of miniaturization and reliability, the thermoelectric refrigeration is attracting increasing attention recently. The performance of the thermoelectric refrigeration depends closely on the figure of merit(ZT) of the material. The Bi2Te3 compound semi- conductors are best known bulk thermoelectric materials near room temperature regime. In this study, thin film forms of the Bi2Te3 compound semiconductors were prepared by sputter deposition method. The Bi/Te bilayer thin films were deposited on SiO2 substrate in sequence, then transformed into Bi-Te compound by thermal treatment through solid state reation. The thickness ratio of Bi/Te bilayer structures and thermal annealing condition on the composite and the thermoelectric properties of the Bi-Te composite thin films was investigated. The results show that the Seebeck coefficient changed from -38.3μV/K to -201.3μV/K, the resistivity increased slightly from 2.02□10-3μΩ-cm to 2.33□10-3μΩ-cm, and the thermal conductivity decreased from 2.56 W/ m□K to 0.71 W/m□K when the Bi-Te composite thin films was annealed at 200℃ for 24 hours. The maximum ZT were 0.735 in this condition near room temperature. The compound phase was identified by x-ray diffraction technique, the morphology and the interdiffusion at the interface of Bi/Te bilayer thin films were examined by Scanning Electron Microscope(SEM).

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