本研究旨為探討在本質非晶矽薄膜製程中，電漿特性對薄膜特性之影響，內容包含模擬與實驗。模擬利用二維流體模型模擬在電漿輔助化學氣相沉積(Plasma enhance chemical vapor deposition, PECVD)系統中的電漿行為，並透過分析模擬結果比較電漿特性與操作參數之關聯性，實驗則利用電漿光譜分析特徵譜線與非晶矽薄膜特性的關聯性，同時以實驗結果與模擬配合相互驗證。
模擬結果顯示，當降低功率時，可使往基板方向之Si4H9/SiH3減少，並可降低鞘層電位差，使離子轟擊效應減少；然而，H/SiH3通量密度比隨功率降低而減少。而當氫氣稀釋比提升時，到達表面之H/SiH3會提升；而Si4H9/SiH3為先上升後下降的趨勢變化。另一方面，當射頻頻率增加時，往基板方向之H/SiH3、Si4H9/SiH3粒子通量密度皆變多，而鞘層電位差降低，預估離子轟擊效應將會降低。
實驗結果顯示，使用頻率為27.12 MHz PECVD來沉積與模擬參數相同之非晶矽薄膜中，其中鈍化效果最好的參數為在功率密度為0.048 W/cm2、氫氣稀釋比為1.5的條件下沉積非晶矽薄膜，其少數載子壽命為5.061 ms。欲瞭解電漿與其放射光譜之關聯，利用穩態電漿光譜分析可觀察到H2 Fulcher與模擬中電子密度隨參數變化的趨勢相似。當分析薄膜鈍化效果與光譜間之關係，可發現少數載子壽命與電漿光譜積分強度比SiH/Hβ*(5 nm)趨勢相似。在模擬與薄膜特性間之關聯性中，發現H/SiH3與薄膜的結晶率以及微結構的趨勢相似；而Si4H9/SiH3則是與孔洞比率的趨勢符合。根據模擬與實驗的結果，若操作在較低功率、適當的氫氣稀釋比例、射頻頻率下，推測可獲得較好的薄膜品質。

The purpose of this study is to investigate the influence of the plasma property on the thin film property. This study includes both experimental and simulation analysis, the simulation part used a two-dimensional fluid model for PECVD (Plasma enhanced chemical vapor deposition) system with silane/hydrogen plasma for the process of the intrinsic amorphous silicon thin film layer through computer simulation, also we can understand the mechanisms of physical and chemical reactions, and comparing the properties of plasma with different process conditions through the simulation results. The experimental part used the plasma spectrum to analyze the correlation between the characteristic spectrums and the properties of the amorphous silicon film layer. At the same time, using the experiment result to match and prove the simulation.
In the simulation result, the flux density ratio of Si4H9/SiH3 decrease as power decrease, also it decreases the ion bombardment effect due to the lower potential gradient in the sheath. However, the flux density ratio of Si4H9/SiH3 decrease as power decrease. As the hydrogen dilution ratio increases, the H/SiH3 increases; and the Si4H9/SiH3 has a trend of rise first then fall. As radio frequency increases, the H/SiH3 and the Si4H9/SiH3 increase. The ion bombardment effect is proportional to frequency.
In the experimental results, depositing the amorphous silicon thin layer by PECVD under the same parameters from simulation at frequency 27.12 MHz. The best passivation quality was deposited under condition are power is 30 W, hydrogen dilution ratio is 1.5. The minority carrier lifetime is 5.061 ms..
To understand the correlation between the properties and the emission spectrum of the plasma more, using plasma spectrums, H2 Fulcher can observe the similar trend with electron number density at the steady-state plasma. To analyze the correlation between a-Si passivation quality and plasma spectrum, it could find the trends of the plasma spectrum SiH/Hβ*(5 nm) is proportional to the minority carrier lifetime.
Comparing the simulation result with properties of a-Si, it could find that the flux density ratio H/SiH3 is similar with the crystallinity and microstructure of the film. The trend of the flux density ratio Si4H9/SiH3 matches with the voids fraction. In conclusion, we could get the better film quality when operating with a lower power, moderate hydrogen dilution ratio and frequency.

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