文献类型：期刊文献

英文题名：Ohimc Contact Formation Mechanism of Silver-Aluminum Paste Metallization on the p+ Emitter of n-Type Crystalline Silicon Solar Cells

作者：Sun, Xinjie[1];Xing, Juanjuan[2];Yang, Yunxia[1];Yuan, Xiao[1];Li, Hongbo[1];Tong, Hua[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Minist Educ, Key Lab Ultrafine Mat, Shanghai 200237, Peoples R China;[2]Shanghai Univ, Sch Mat Sci & Engn, Shanghai 200444, Peoples R China

年份：2022

卷号：51

期号：10

起止页码：5717

外文期刊名：JOURNAL OF ELECTRONIC MATERIALS

收录：;EI(收录号：20223012397862);WOS:【SCI-EXPANDED(收录号:WOS:000827334200001)】；

基金：This work is supported by the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Crystalline silicon solar cells; Ag-Al paste; ohmic contact; metallization

摘要：The development of high-efficiency n-type crystalline silicon (c-Si) solar cells primarily depends on the application of silver-aluminum (Ag-Al) paste metallization. To deeply reveal and clarify the formation mechanism of the ohmic contact between Ag-Al paste and the p(+)-Si emitter, the microstructure of the Ag/Si contact interface and the migration of Al to the interface during sintering were investigated. The results showed that the sintered Ag/Si interface contained a glass phase layer with a thickness less than 500 nm, in which a large number of Ag colloids were embedded. This is the same as the Ag/Si contact interface formed by Ag paste metallization on p-type c-Si cells. Compared with Ag paste, Ag-Al paste provides a considerably lower contact resistance with the p(+) emitter. Electrical tests revealed a smaller Ag/Si contact resistance and higher Ag electrode resistance with increasing Al concentrations in the Ag-Al paste. In the study of the action mechanism of Al, scanning electron microscopy images illustrated that during sintering, Al powder dissolves in the glass melt at similar to 600 degrees C and reaches the contact interface with the flowing glass melt. As the temperature exceeded 700 degrees C, the mutual diffusion of Al-Si across the Ag/Si contact interface enables Al to enter the Si substrate. The electrochemical capacitance-voltage test results confirmed that the p-type doping concentration of Al in the Si surface significantly increased, leading to a reduction in the shunt resistance. Consequently, the formation of Ag/Si ohmic contact with significantly low contact resistance was completed.