光伏效率之快速提升技術

Abstract

在本論文中，提出三種方法來改善矽晶圓太陽能電池效率：金氧半結構太陽電池、利用浸沒式電漿離子佈值技術鈍化修補太陽電池表面缺陷和施加外應力於太陽電池以增加載子遷移率。 在結構上，製作了Al/SiO2/ p-type與ITO/SiO2/ n-type 兩種不同金氧半結構太陽電池元件，相較於鋁電極來說，因為ITO電極材料的介面特性，缺陷數較多，並無得到較鋁電極佳的光電轉換效率，亦透過ISE模擬軟體理論分析金氧半結構太陽電池。 製程上，利用浸沒式電漿離子佈值技術，對太陽能電池表面做氫鈍化層保護，降低表面複合速率，藉以增加光電流，太陽電池的光電效率可增強約16%。表面複合速率對太陽能電池參數影響透過模擬軟體研究。 最後，將現今廣泛應用於邏輯電路元件的應變矽技術，施加於矽晶圓太陽能電池上，藉由模擬軟體(ISE)來模擬與研究，模擬結果顯示此應力將會減少半導體能隙並增加光吸收，同時增強載子的遷移率，效率提升大約1.5%。

In the present document, three different initiatives taken on behalf of efficiency improvement of wafer based solar cells are presented. First, MIS Solar cells are theoretically analyzed and the outcome is verified by means of TCAD simulation software. Al/SiO2/ptype Si and ITO/SiO2/nType Si devices are constructed and tested obtaining negative results that discard the utilization of transparent conductive oxides as promising contact materials for MIS solar cells. The influence of front surface recombination on solar cell behavior is examined and an improvement methodology for this parameter by means of PIII technology is derived. PIII acts as a passivation method that tends to decrease the surface defects and hence decreases the surface recombination velocity. Experimental results reflect an efficiency increase of 16%. Finally the impact of mechanically induced strain on solar cells is studied and modeled by software means. Results reveal a reduction in the semiconductor bandgap and a modification of the carrier mobilities that are translated into a 1.5% efficiency augmentation.