Single Grain Boundary Modeling and Design of Microcrystalline Si Solar Cells

Chu-Hsuan Lin; Wen-Tzu Hsu; Cheng-Hung Tai

doi:10.3390/ma6010291

Single Grain Boundary Modeling and Design of Microcrystalline Si Solar Cells

Materials (Basel). 2013 Jan 21;6(1):291-298. doi: 10.3390/ma6010291.

Authors

Chu-Hsuan Lin¹, Wen-Tzu Hsu², Cheng-Hung Tai³

Affiliations

¹ Department of Opto-Electronic Engineering, National Dong Hwa University, Shoufeng, Hualien 97401, Taiwan. chlin0109@mail.ndhu.edu.tw.
² Department of Opto-Electronic Engineering, National Dong Hwa University, Shoufeng, Hualien 97401, Taiwan. m9925003@ems.ndhu.edu.tw.
³ Department of Opto-Electronic Engineering, National Dong Hwa University, Shoufeng, Hualien 97401, Taiwan. m9724010@ems.ndhu.edu.tw.

Abstract

For photovoltaic applications, microcrystalline silicon has a lot of advantages, such as the ability to absorb the near-infrared part of the solar spectrum. However, there are many dangling bonds at the grain boundary in microcrystalline Si. These dangling bonds would lead to the recombination of photo-generated carriers and decrease the conversion efficiency. Therefore, we included the grain boundary in the numerical study in order to simulate a microcrystalline Si solar cell accurately, designing new three-terminal microcrystalline Si solar cells. The 3-μm-thick three-terminal cell achieved a conversion efficiency of 10.8%, while the efficiency of a typical two-terminal cell is 9.7%. The three-terminal structure increased the J_SC but decreased the V_OC, and such phenomena are discussed. High-efficiency and low-cost Si-based thin film solar cells can now be designed based on the information provided in this paper.

Keywords: grain boundary; microcrystalline silicon; three-terminal cell.