由於非晶矽薄膜太陽能電池在長期照光後，非晶矽吸收層的能隙較大，所以無法有效吸收長波長的光，並且非晶矽薄膜隨使用時間增長而有光劣化的現象產生，導致非晶矽薄膜太陽能電池的轉換效率變低。為了改善上述非晶矽單一吸收層缺點，本論文結合非晶矽及微晶矽的各別互補優點，採用雙層本質非晶矽/本質微晶矽吸收層製作薄膜太陽能電池。因非晶矽的吸收係數較微晶矽大，故可以設計厚度較薄的吸收層，而微晶矽的能隙比非晶矽低，對於較長波段的光吸收能力較好，且較不容易有光劣化的現象。
本論文利用二氧化碳雷射輔助電漿增強式化學氣相沉積系統沉積本質微晶矽薄膜，並將其應用於製作p-非晶碳化矽/i-非晶矽/i-微晶矽/n-非晶矽薄膜太陽能電池，其太陽能電池的光電效率從非晶矽為單一吸收層之4.59 %提升至5.69 %。
除此之外，由於 p層與i層之間存在能隙差，因此在接面間會因能隙不連續而產生一能位障，增加光生載子在此處產生的復合機率，使載子無法順利被萃取到外部電路，並產生許多漏電路徑，導致整體太陽能電池元件效率下降。本部分研究在於改善p/i接面間的復合現象，在p/i接面間成長一漸變能隙本質非晶碳化矽緩衝層，藉由摻入不同流量比之甲烷，而產生不同本質非晶碳化矽緩衝層能隙值，使p/i接面能位障得以減緩，增加能隙間的連續，藉此改善接面間的缺陷，減少光生載子復合的機率，最終具非晶漸變能隙本質緩衝層之非晶/微晶矽薄膜太陽能電池效率提升至6.62 %。

The weak bonding in amorphous silicon (a-Si) would be broken after the prelonged light illumination. It is the main reason to cause the low conversion efficiency of a-Si solar cells. The effect of light-induced degradation also named Staebler-Wronski effect. Although microcrystalline silicon (μc-Si) could absorb more light with stronger bonding, it exist leakage path at grain boundary and cause higher dark current. In this study, the a-Si/μc-Si solar cells with both type silicon in absorption layer would combine both advantage to applicate the follow-up research. Apart from this, the p/i interface in Si thin film solar cells exist the discontinuity energy band-gap and energy barrier height. It would restrict the charge carrier through the band offset and cause carrier recombination which decrease the conversion efficiency of solar cells. The i-a-SiC buffer layers with graded energy band-gap were inserted at p/i interface of the solar cells in order to improve the band offset. Finally, the advantage of slowing down the discontinuity energy band-gap with the i-a-SiC buffer layers inserted was applied to a-Si/μc-Si solar cells. The conversion efficiency achieved from 5.39 % to 6.62 % for an i-a-SiC buffer layer of thickness 10 nm.

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