可撓式不鏽鋼基板矽薄膜太陽能電池光捕捉研究

The research for light trapping of flexible amorphous silicon thin film solar cell deposited on stainless steel foil substrate

陳孝隆(Shiow-Long Chen)

指導教授 ： 李碩仁

元智大學/工程學院/機械工程學系/博士(2013年)

https://doi.org/10.6838/YZU.2013.00056

摘要

本研究主要開發可撓式不鏽鋼箔基板非晶矽薄膜太陽能電池整體製程技術，並分別應用電化學拋光（EP）及電化學機械拋光（ECMP）技術，於不鏽鋼箔基板製作奈米顯微結構，以提高可撓式矽薄膜太陽能電池效能，完成SS304/Mo/Ag/AZO/p-i-n/AZO電池製程技術開發。研究結果發現，SS304基板經EP與ECMP處理後表面粗糙度分別為Ra 0.052μm; Ra 0.022μm，可得到EP SS304電池開路電壓Voc＝0.64V、短路電流密度Jsc＝10.90mA/cm2、填充因子FF＝55%、轉換效率η＝3.84%，及ECMP SS304電池Voc＝0.77V, Jsc＝11.24mA/cm2, FF＝53%, η＝4.59%，顯示不鏽鋼箔基板經EP與ECMP處理均可有效增加光電流，且ECMP較EP處理之不鏽鋼基板能獲得更高之電池效能。於電池環境測試部份，經-40℃~85℃溫度循環一百次後，電池效率衰退0.33%；經一百次60°反覆撓度測試後，效率衰退0.08%；依ASTM D3359規範，薄膜附著力可達4B等級，百格內脫落率約3%。

關鍵字

非晶矽薄膜太陽能電池 ； 可撓式不鏽鋼箔基板 ； 光捕捉

並列摘要

This study presents a flexible stainless steel（SS） foil substrate for amorphous silicon（a-Si:H） n-i-p thin-film solar cells. The SS substrates are treated by electrochemical polishing（EP） and electrochemical mechanical polishing（ECMP） respectively to form a nano-scale surface morphology. The rough morphology of SS substrate could result in high diffusion reflection but also cause high density of micro-cracks in the deposited photoelectric layers. Therefore, to get a balance between the light trapping performance and the quality of the deposited photoelectric layers is the focus of this study. An a-Si:H thin-film solar cell with SS304/Mo/Ag/AZO/p-i-n/AZO structure using electrochemical treated flexible SS substrate is developed.
The results show that the center line average roughness（Ra） of 0.063 μm and 0.027 μm are achieved by EP and ECMP processes. Then, the PECVD is utilized to deposit the amorphous silicon p-i-n photoelectric layers on the treated SS304 substrate and the efficiency of solar cells is measured. Open circuit voltage（Voc）of 0.64 V, short-circuit current density （Jsc） of 10.90 mA/cm2, fill factor（FF） of 55%, and conversion efficiency（η） of 3.84% are measured on the cell with EP substrate. Voc of 0.77 V, Jsc of 11.24 mA/cm2, FF of 53%, and η of 4.59% are measured on the cell with ECMP substrate. It shows that the stainless steel foil substrates treated by both EP and ECMP processes can effectively increase the light current of the cells but the cell with ECMP substrate has better cell performance than the cell with EP substrate.
In order to understand the reliability of the cells, an environmental test, such as thermal-cycle test (-40℃ ~ 85℃) is carried for a hundred cycles. The efficiency of the thermal-cycle tested cell is decreased by 0.33%. A 60° bending test is carried for a hundred cycles on a cell. The efficiency of the bending tested cell is decreased by 0.08%. For adhesion test, the deposited film can achieve 4B grade of adhesion according to ASTM D3359 standard with a chipping rate about 3%.

並列關鍵字

Amorphous silicon thin film solar cell ； Flexible stainless steel foil substrate ； Light trapping

參考文獻

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