本研究利用二氧化碳雷射輔助電漿增強式化學氣相沉積系統進行本質微晶矽薄膜之鍍製，並將其應用於p-非晶矽化碳/i-微晶矽/n-非晶矽薄膜太陽能電池中。一般非晶矽薄膜太陽能電池在長期照光下，於非晶矽吸收層中會有光劣化現象的產生，進而導致太陽能電池的轉換效率下降。為改善此現象，本研究利用微晶矽薄膜取代非晶矽薄膜作為矽基薄膜太陽能電池的吸收層，因微晶矽薄膜與非晶矽薄膜相比，具有較高的載子遷移率，且其具有較低的能隙，所以可以增加太陽能電池對長波長的光之吸收能力。因此以微晶矽薄膜作為矽基薄膜太陽能電池的吸收層，其可改善太陽能電池的轉換效率，使元件效率由以非晶矽為吸收層的4.67 %提升至5.50 %。另一方面，以雷射輔助電漿增強式化學氣相沉積系統所製備之微晶矽薄膜與非晶矽薄膜相比，其具有較低的能隙值，此時p/i接面因能隙值差異，而導致能隙不連續及接面間的能位障，並產生能帶偏移，因而在接面間會有較多的復合中心存在，其會造成光生載子被復合的機率增加，所以部分的光生載子無法有效地被順利萃取出來，並產生漏電路徑，限制了整體太陽能電池元件效率。本研究為改善在p/i接面的復合現象，因此於p/i接面成長漸變能隙本質微晶矽化碳緩衝層，藉由摻入不同流量比之甲烷，調變本質微晶矽化碳緩衝層能隙值，使p/i接面能位障得以減緩，能隙可以連續，藉此改善接面間的缺陷，減少光生載子被復合的機率，最終具微晶漸變能隙本質緩衝層之矽基薄膜太陽能電池效率提升至6.31 %。

In this thesis, the intrinsic microcrystalline silicon (μc-Si) films was deposited using laser assisted plasma enhanced chemical vapor deposition (LAPECVD) system and applied to p-i-n thin film solar cells. After the prolonged light illumination, the efficiency of amorphous silicon (α-Si) thin film solar cells was decreased because of the light-induced degradation in the absorption layer. To improve the above mention, the μc-Si films were utilized to replace the α-Si films as the absorption layer for Si-based thin film solar cells. Compared with the α-Si films, the μc-Si films had higher carrier mobility and lower energy bandgap, which could increase the absorption ability at long wavelength of light. Consequently, the conversion efficiency of Si-based thin film solar cells used μc-Si thin film as the absorption layer was improved from 4.67 % to 5.50 %. In addition, the lower energy band-gap of μc-Si films using LAPECVD system caused the energy band-gap discontinuity and energy barrier height at the p/i interfaces, which generated band offset, critical carrier recombination, and numerous leakage current during the photocurrent extraction. Therefore, the conversion efficiency of solar cells was restricted. In this thesis, the i-c-SiC buffer layer with graded energy bandgap was inserted to p/i interface by varying the flow ratios of silane to methane to improve the energy bandgap discontinuity and the defect at p/i interface, which could reduce the carrier recombination probability within p/i interface. Finally, the conversion efficiency of Si-based thin film solar cells with microcrystal graded-bandgap intrinsic buffer layer was further enhanced to 6.31 %.

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