Analysis of the interdigitated back contact solar cells:The n-type substrate lifetime and wafer thickness

作     者：张巍 陈晨 贾锐 孙昀 邢钊 金智 刘新宇 刘晓文 Zhang Wei;Chen Chen;Jia Rui;Sun Yun;Xing Zhao;Jin Zhi;Liu Xin-Yu;Liu Xiao-Wen

作者机构：Institute of MicroelectronicsChinese Academy of Sciences Xinjiang Vocation & Technical College of Construction 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2015年第24卷第10期

页      面：638-643页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Project supported by the Chinese Ministry of Science and Technology Projects(Grant Nos.2012AA050304 and Y0GZ124S01) the National Natural Science Foundation of China(Grant Nos.11104319,11274346,51202285,51402347,and 51172268) the Fund of the Solar Energy Action Plan from the Chinese Academy of Sciences(Grant Nos.Y3ZR044001 and Y2YF014001) 

主　　题：lifetime wafer thickness interdigitated back contact solar cells technology computer-aided de- sign 

摘      要：The n-type silicon integrated-back contact（IBC） solar cell has attracted much attention due to its high efficiency,whereas its performance is very sensitive to the wafer of low quality or the contamination during high temperature fabrication processing, which leads to low bulk lifetime τbulk. In order to clarify the influence of bulk lifetime on cell characteristics, two-dimensional（2D） TCAD simulation, combined with our experimental data, is used to simulate the cell performances, with the wafer thickness scaled down under various τbulk conditions. The modeling results show that for the IBC solar cell with high τbulk,（such as 1 ms-2 ms）, its open-circuit voltage V oc almost remains unchanged, and the short-circuit current density J sc monotonically decreases as the wafer thickness scales down. In comparison, for the solar cell with low τbulk（for instance, 〈 500 μs） wafer or the wafer contaminated during device processing, the V oc increases monotonically but the J sc first increases to a maximum value and then drops off as the wafer＇s thickness decreases. A model combing the light absorption and the minority carrier diffusion is used to explain this phenomenon. The research results show that for the wafer with thinner thickness and high bulk lifetime, the good light trapping technology must be developed to offset the decrease in J sc.