大面積紅外線光感測器元件須具有高操作速度、高光增益且低溫製程可製作大面積Array型式者。以往文獻報導，有以非晶矽/非晶矽鍺(Si1-xGex)材料製作不但可在玻璃基板上進行大面積成長，且光吸收特性佳，並可獲得較高的光增益。但由於非晶矽/矽鍺(Si1-xGex)材料之載子移動率(mobility)低，限制其操作速度而無法製作高速之紅外光感測元件。也有採用具有高移動率及導電性佳之複晶矽/矽鍺材料者，但其製程溫度又太高，只能在矽晶片基板上成長，無法製成大面積 array 式。至於低溫複晶矽雖可成長在大面積之玻璃上但製作時不易均勻，且具較高成本。本文使用改良式PECVD疊層技術，利用氬原子電漿處理技術來成長奈米矽鍺薄膜，藉由較重的Ar原子，能更快更有效率的打斷通入SiH4及GeH4的Si、Ge的鍵結，進而更有效結合成 nc-SiGe薄膜

本論文發展出成長奈米複晶矽鍺之最佳製程參數，可長出載子遷移率高達為99.1 cm2/v*s的nc-SiGe薄膜，且成長率較一般傳統疊層技術增加30%左右，並利用FeSEM、AFM觀察薄膜的表面， Hall measurement量測載子移動率作為電性分析依據，以及使用Raman spectra、FTIR等儀器分析薄膜的結晶品質，使用PL及Spectra Pro500來量測其吸收光譜及吸收係數，再用最佳成長I-type奈米複晶矽鍺參數及通入磷及硼來摻雜製作P-type和N-type奈米複晶矽鍺。最後以所得到之最佳參數在玻璃基板上製作PIN結構的奈米複晶矽鍺薄膜光二極體元件，並量測其I-V curve及響應速度，據此探討其使用於紅外光感測器之可行性及優缺點。

A large-area IR detector must have high operation speed, high photo-gain, and could be prepared in large-area array type. Materials, such as a-Si or a-SiGe grown on the glass substrates has high absorption coefficient, and high photo-gain. However, their mobility are too low to work in high speed. While the materials, poly Si or poly SiGe has high mobility and conductivity, but their processing temperatures are too high to grow on large-area glass substrate for forming a large- area array. Even the LTPS (Low Temperature Poly Silicon) can be deposited on large-area, but its uniformity is bad, and cost is high. In this work, we use improved layer-by-layer method (ILBL), which takes the advantage of argon plasma annealing to break the bonds within Si and Ge compound fast and effectively, thus enhances the growth rate.

In this thesis, firstly, we developed the nc-SiGe thin films with the ILBL technology to grow the higher mobility (about 99.1 cm2/v*s) nc-SiGe films. The growth rate is about 60nm/cycle, which is 30% larger than traditional layer by layer technology. Additionally, we optimized the best growing parameters to prepare PIN photodiodes and studied their performance for IR photodetecting application. We investigated physical, optical and electrical characteristics of the films by Fe-SEM, AFM, Hall measurement, Raman spectrum, Photoluminescence, Spectra Pro500 respectively. The IR detecting characteristics were examined by photo and dark current ratio, responsitivity, and response speed measurement.

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