以HDP-CVD 製備之微晶矽鍺薄膜與其微結構光電特性之研究

Study of Microstructure and Photoelectrical Properties for Microcrystalline Silicon Germanium Thin Film Prepared by HDP-CVD

陳坤賢(Kun-Xian Chen)

指導教授 ： 廖慶聰

共同指導教授 ： 楊茹媛(Ru-Yuan Yang 楊茹媛)

崑山科技大學/工程學院/機械工程研究所/碩士(2009年)

摘要

本實驗主要是利用高密度電漿化學氣相沉積系統(High Density Plasma Chemical Vapor Deposition，HDP-CVD)製備之微晶矽鍺薄膜（μc-Si1-XGeX）薄膜，以作為薄膜太陽能電池之半導體材料。本實驗以改變基板溫度、射頻功率、鍺烷、矽甲烷及氫氣流量沈積出各種不同微晶矽鍺薄膜， 試片將以微拉曼光譜分析儀(micro Raman Spectrometer)；傅利葉轉換紅外線光譜儀(Fourier Transform Infrared Spectrometer, FTIR)；薄膜X 光繞射儀(X-Ray Thin Film Diffractometer, XRD)；場發射穿透式電子顯微鏡（Field Emission Transmission Electron Microscope,TEM）；霍爾量測（Hall Measuremnet）及紫外光/可見光吸收光譜儀(UV-visible spectroscopy)等設備的分析結果來瞭解微晶矽鍺之微結構、電特性及光學等其他特性。

由實驗結果可得知，提升基板溫度與射頻功率此二參數，均可改善微晶矽鍺薄膜之微結構、電特性及光學特性。在結構上可有效改善微晶矽鍺薄膜之結晶度，最高結晶度可達70% ；在電性上可增加其載子移動率至34 cm2/V-s，光學特性上也可增加光譜吸收範圍達可見光由500nm 至900nm 及紅外光1100nm 和1600nm。但改變鍺烷比例未有較顯著的影響到薄膜的各種特性之結果。

關鍵字

微晶矽鍺 ； 高密度電漿化學式氣相沈積 ； 薄膜太陽能電池

並列摘要

To improve the efficiency of the solar cell device, a microcrystalline silicon-germanium (μc-Si1-xGex) thin film fabricated by a high density plasma chemical vapor depo-sition is studied. Several process parameters, such as the gas flows of GeH4、SiH4 and hydrogen(H2), the substrate
temperature, and the radio frequency (RF) power, are selected to deposit μc-Si1-xGex thin films, and then to investigate the effects of these parameters on the perfor-mance of μc-Si1-xGex thin films. The structural, optical, and electrical properties of μc-Si1-xGex thin films are
quantitatively measured by Raman spectrum, FTIR, X-Ray, TEM, Hall measurement, UV-visible, and etc..
From the results, it can be observed that the relative crystall-inity, the mobility, and the range of optical absorption spectrum of μc-Si1-xGex thin films are increased as the substrate temperature and RF power increase.
Moreover, the crystallinity factor of μc-Si1-xGex films deposited at higher substrate temperature for each dilu-tion ratio is about 80%. In addition, the best value of mobility is almost reached to 34 cm2/V-s, and the range of absorption spectrum is either from 500nm to 900nm at visi-ble spectrum or from 1100nm to 1600nm at infrared spectrum.
Nevertheless, results also reveal that changing the dilu-tion ratio of GeH4 won’t improve the performance of μc-Si1-xGex thin films.

並列關鍵字

Microcrystalline Silicon-Germanium ； High density plasma chemical vapor deposition ； Thin film solar cell

參考文獻

＂，崑山科技大學機械工程系碩士論文，(2008) 。

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