不鏽鋼基材矽薄膜太陽能電池研製

The Study and Processes of Silicon Thin Film Solar Cell on SS304 Stainless Steel Substrate

施丞鴻(Cheng-Hong Shih)

指導教授 ： 李碩仁

元智大學/工程學院/機械工程學系/碩士(2011年)

https://doi.org/10.6838/YZU.2011.00065

摘要

本研究在開發SS304不鏽鋼基板矽薄膜太陽能電池，以半導體模擬來作參數研究，製訂製程參數，並定義各層結構、參數變化的增益與損失。接下來，製作以Asahi (U type)玻璃製作baseline，作為參考基礎，透過各種金屬鍍層與TCO的搭配，調整兩者的製程參數，令矽膜電池能穩定的成長在不鏽鋼片上。在完成全製程開發後，本研究以MEMS技術，嘗試開發具光捕捉微結構基板，研究以light-tapping增加電池效率的方法，並研究具微結構基板用於太陽能電池上的可行性。
本文利用了TCAD的模擬，首先驗證了n入光與p入光的效能損失差異，就模擬實驗結果，p入光的結構較n入光的結構多了1.2%的效率。並利用模擬軟體定義出PECVD製程參數表，作為實驗基礎組。
在電池製作方面，實驗的結果顯示，Mo金屬膜層可以作為熱膨係數的緩衝層，修補介面缺陷，且SIMS的結果顯示，Mo層可以減少金屬離子的汙染，降低半導體內的載子複合中心數量，提升電池的Voc值。由於Fe和Mo的反射率不佳，因此製作Ag來增加背電極的反射率，來增加電池的Jsc。搭配Mo與Ag的製程，可以令不鏽鋼太陽電池得到：Voc = 0.78、Jsc = 9.54 mA/cm2、FF = 0.55和η = 4.12 %的結果。本研究也提出使用AZO膜層置於Ag與矽膜接面間，修補介面的接合缺陷。令電池的FF從55%提昇到62%。

關鍵字

不鏽鋼基板 ； 矽薄膜太陽能電池

並列摘要

Glass substrate is now mostly using in silicon thin film solar cell. However, there are some disadvantages such as expensive and low mechanical strength on it. For solving these problems, domestic and foreign research institutes have studied a replacement for the substrate and common using plastic and stainless steel foils. This study’s object is a development for silicon thin film solar cell on stainless steel substrates instead of glass.
This research used TCAD simulation to development PECVD parameter. we used thickness 600μm SS304BA as cell substrate and compared the cell performance to Asahi U type glass one. To made the stable process of stainless steel substrates solar cell, we fabricated metal and AZO layers on stainless steel substrates. At last, we use light trapping micro- structures fabricated on stainless steel substrates made by MEMS lift-off process and chemical etching, to increased solar cell efficiency.
According to TCAD simulation we investigate the efficiency of solar cell using p-layer as window layer is higher than n-layer by 1.2 %. And then, we used TCAD simulation to development stainless steel substrates solar cell process parameters.
The cell on SS304BA had poor conversion efficiency especially on open current voltage (Voc), and we made some hypothesis that the iron ions of substrate were the main reason what doped into silicon layers during processing. Therefore, we deposited molybdenum layer directly on substrate as barrier layer for preventing from ions diffusion. In order to upgrade the Jsc, we use the Ag layer to increase the reflection rate. This study investigate the best solar cell efficiency as follow: Voc = 0.78、Jsc = 9.54 mA/cm2、FF = 0.55 and η = 4.12 %.

並列關鍵字

Stainless Steel Substrate ； Silicon Thin Film Solar Cell

參考文獻

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