本研究以三甲基硼(TMB)為摻雜物，使用射頻電漿輔助化學氣相沉積系統(RF-PECVD)於玻璃基材上成長p型非晶碳化矽以及p型微晶矽薄膜，並分析其結構及光電性質，期望能製備出適用於薄膜太陽能電池的p型窗口層。實驗結果顯示，藉由通入甲烷能成功提升薄膜的光學品質，當甲烷對矽甲烷流量比為2時，非晶碳化矽薄膜的暗導電率為4.9 10-7 S/cm，且光學能隙達2 eV以上，其透光性明顯優於非晶矽薄膜。另一方面，隨著氫氣稀釋比的提高，薄膜由非晶矽轉變成微晶矽的結構，以氫氣對矽甲烷稀釋比100、基材溫度220oC所成長出厚度為85 nm的p型微晶矽薄膜，其結晶體積分率約52%，暗導電率達10-1 S/cm以上。我們進一步將沉積時間縮短，即使厚度縮小至35 nm，經由氬氣下的退火處理後，亦能獲得暗導電率為10-2 S/cm的微晶矽薄膜。

In this thesis, the p-type amorphous silicon carbide (a-SiC) and p-type hydrogenated microcrystalline silicon (μc-Si:H) films were deposited on glass by radio-frequency plasma enhanced chemical vapor deposition (RF-PECVD) using trimethylboron (TMB) as the doping source. For optimization of the window layer, the dependence of electrical and optical properties were investigated.
In the first part, we deposited p-type a-SiC with methane and silane. The dark conductivity and optical gap of the film deposited at [CH4]/[SiH4]=2 were 4.9 10-7 S/cm and 2 eV, respectively. The result showed that the films were more transparent than amorphous silicon.
In the second part, the crystalline volume fraction of μc-Si:H were enhanced with increasing hydrogen dilution. The crystalline volume fraction of 52% and dark conductivity of 1.31×10-1 S/cm can be achieved under the following condition: [H2]/[SiH4]=100 and Ts=220oC. This result showed that the film with thickness of 85 nm possessed a good electrical property. However, it’s too thick for the window layer in the thin film solar cell. Finally, a thinner film with thickness of 35 nm which we deposited had a high dark conductivity around 10-2 S/cm after the sample annealed under Ar atmosphere at 200oC for 1 hr, and it was suitable for thin film solar cell.

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