臺灣博碩士論文加值系統

背接式太陽能電池效率比傳統矽晶太陽能電池高上不少，但其製造成本複雜又昂貴，使其無法成為市場主流。在本研究中，我們使用目前市場上技術成熟且大量使用成本又較低廉的絲網印刷及Cz-P型矽晶片，進行指叉背接型太陽能電池（IBC）的製造和特性分析。此實驗製造出來的太陽能電池為10平方公分，轉換效率為20.08％，其中，開路電壓為645mV，短路電流密度40.15 mA / cm2，填充因子77.51％。此外，電池性能也通過基於所測量的電學性質的分析計算而得到驗證。從我們的分析計算的結果看來，採用適當的射極設計，絲網印刷的p-Si指叉背接型太陽能電池能達到680mV的開路電壓和22％的轉換效率。在本實驗中，背面接觸鈍化（PERC）電池可以獲得與絲網印刷的IBC電池相當的效率，IBC電池可以藉由改善背面的射極的飽和電流來提升效率，PERC電池也可以有相同的效果只要前表面射極的改進不影響電池的光吸收。

In this study, we report on the fabrication and analytical characterization of the screen-printed p-Si interdigitated back contact (IBC) cells with the conversion efficiency of 20.08%, with open-circuit voltage of 645 mV, short-circuit current density of 40.15 mA/cm2, and fill factor of 77.51%. The cell performance has also been confirmed with the analytical calculation based on the electrical properties measured. It also shows that, with the proper emitter design, the open-circuit voltage of 680 mV and conversion efficiency of 22% is possibly attainable for the screen-printed p-Si IBC cell. Compared with the screen-printed IBC cells, the passivated emitter and rear “contact” (PERC) cell may perform equivalently well, provided that any improvement on Seff of the front surface does not compromise the light absorption and emitter resistance of the cell.

Table of Contents iv
List of Figures vi
List of Tables ix
Chapter 1 Introduction 1
1.1 Motivation 1
1.2 Outlines 3
Chapter 2 Literature reviews 5
2.1 Generation and recombination 5
2.1.1 Generation 5
2.1.2 Recombination mechanisms and lifetime 6
2.1.3 Effective lifetime 14
2.2 Silicon solar cells 14
2.2.1 Working principle 14
2.2.2 IV curve and efficiency 17
2.2.3 Short-circuit current 18
2.2.4 Open-circuit voltage 20
2.2.5 Fill factor 22
2.3 Review of back contact solar cells 23
2.3.1 Metallization wrap through solar cells (MWT) 24
2.3.2 Emitter wrap through solar cells (EWT) 24
2.3.3 Interdigitated back contact solar cells (IBC) 25
Chapter 3 Measurements 30
3.1 Minority carrier lifetime measurement from photoconductance decay 30
3.2 Quasi-steady state photoconductance decay 32
3.3 Saturation current from WCT-120 34
3.4 Lifetime measurement of ALD Al2O3 on BSF surface 35
Chapter 4 Experiments 38
4.1 Cell design and test 38
4.2 Cell fabrication and structure 41
4.3 Cell performance and effective surface recombination 45
Chapter 5 Analysis 50
5.1 Analysis of Voc 50
5.2 Analysis of Jsc 52
5.2.1 Non-uniform generation rate and absorption 57
5.3 Analysis of FF 60
Chapter 6 Conclusions 68
References 70

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