高效率薄膜太陽能電池之元件製作與分析

Abstract

目前低溫矽薄膜太陽能電池的轉換效率仍然低於單晶矽太陽能電池。大部分的轉換效率損失來自於各層塊材缺陷、介面缺陷與光致劣化現象。近幾年來，許多研究發展高能隙的透光層(Window layer)與導電微晶矽薄膜來改善膜薄太陽能電池的轉換效率，但是不同薄膜的不連續能隙會增加介面缺陷的影響而降低太陽能電池的效率。在此論文裡，我們分別製作非晶矽元件與微晶矽元件，各別探討其薄膜型太陽能電池的特性分析與薄膜缺陷狀態對於效率的影響。 對於非晶矽元件,我們希望能獲得較佳的透光層來提升非晶矽元件的效率。因此本論文中，探討不同透光層的特性並且藉由製程來改善其元件特性。 對於微晶矽元件，我們希望能提高沉積速率並且同時保持高效率元件特性。此外，近幾年來有相關研究指出高壓沉積方式可以達到上述目標。本論文中我們將探討不同壓力沉積下得元件特性，並且利用不同分析方式來探討元件特性，如利用DLCP、QE、活化能。

The efficiency of low temperature silicon thin film solar cell is still lower than single crystallization solar cell. The most losses of efficiency come from the bulk trap、interface trap and light induced degradation. In recent year, most researches developed the window layer of higher energy band gap and conductive micro-Silicon to improve the efficiency of thin film. But discontinues energy gaps of different layer will increase the influence of interface trap and decrease the efficiency of solar cell. In this thesis, we fabricate respectively amorphous silicon and microcrystalline silicon thin film solar cell, and the characteristic analysis and efficiency influenced by the thin film trap state applied on thin film solar cell will be discussed. For amorphous silicon thin film solar cell, we hope obtain greater window layer to enhance the efficiency of amorphous silicon thin film solar cell. In this thesis, we study different window layer characteristics and we also change the process parameter to improve. We hope use high deposition rate and maintain higher cell efficiency for microcrystalline silicon thin film solar cells. Otherwise, researches indicate that high-pressure way to achieve these goals in recent year. In this thesis, we will study device characteristics by different deposition pressure and use different analysis method such as drive level capacitance profiling (DLCP) 、QE、and activation energy to analyze solar cells.