隨著平面顯示器產業的快速發展，薄膜電晶體的設計及改良頓成為重要課題。目前廣為應用的非晶矽薄膜電晶體雖然可以大面積且低溫均勻成長，但驅動電流較低是其最大的缺點。近來積極研究的高溫複晶矽薄膜電晶體雖擁有大驅動電流，但其需高溫製程不利於玻璃基板上成長。至於低溫複晶矽則於大面積製作時不易均勻，且具較高成本。於是吾人利用PECVD疊層氫原子電漿處理技術(Hydrogen plasma treatment)來成長奈米矽鍺薄膜電晶體，不但保有目前非晶矽薄膜技術的優點可以低溫(250℃)下大面積成長，而且可以大幅提升其載子遷移率進而提升驅動電流，增加開關電流比。

本論文發展出p、i、n三種type之奈米複晶矽鍺薄膜的最佳製程參數，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、XRD等儀器分析薄膜的結晶品質。最後吾人以奈米複晶矽鍺取代非晶矽應用於在薄膜電晶體之通道層，分別在矽基板以及玻璃基板上製作奈米複晶矽鍺薄膜電晶體，並量測其Transfer characteristic和I-V curve，據此探討其使用於液晶顯示器之優缺點。

Thin film transistors (TFTs) have been employed extensively to drive and address each pixel in the flat panel displays. Amorphous TFTs have the advantages of low temperature and simple deposition, but also possess the drawback of poor current driving ability. Instead, poly-silicon TFTs are widely studied for their high mobility. However, the high fabrication temperature prevents it from using glass substrate. On the other hand, the low temperature poly-silicon (LTPS) that usually annealed with excimer laser annealing (ELA) on amorphous silicon still have the non-uniformity issue for production in large area and the extra annealing also cost a lot.

In this thesis, we developed the nc-SiGe thin films with a novel method of layer-by-layer hydrogen plasma treatment. This method is not only effective but also compatible to the convention amorphous silicon TFTs technology. The nc-SiGe films have higher mobility than amorphous silicon films and can be uniformly deposited at low temperature (250℃). Additionlly, we optimized the best growth parameters to fabricate the p-type, n-type and intrinsic type nc-SiGe, respectively. Furthermore, we also investigated physical and electrical characteristics of the films by Fe-SEM, AFM, Hall measurement, Raman spectrum and XRD, correspondingly. Finally, we apply the developed nc-SiGe thin films to prepare TFT and studied their performance for flat panel display applications.

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