Aluminum fire-through with different types of the rear passivation layers in crystalline silicon solar cells

作者：Song Joo Yong; Park Sungeun; Kim Young Do; Kang Min Gu; Tark Sung Ju; Kwon Soonwoo; Yoon Sewang; Kim Donghwan^*

来源：Metals and Materials International, 2012, 18(4): 699-703.

DOI：10.1007/s12540-012-4020-0

• aluminum
• silicon nitride
• local contact
• rear passivation
• back surface field
• solar cell

Aluminum penetration during dielectric layer annealing on silicon was studied for solar cell application. The thickness and uniformity of the aluminum-doped region was examined in variously annealed dielectric layers. Three types of silicon wafers were used with (1) bare Si, (2) SiO2 layer (80 nm)/Si, and (3) SiNX layer (80 nm)/Si. Local metal contacts were made through laser-drilled holes, and annealing was tested at four different temperatures. Reactions between aluminum and silicon were observed by cross-sectional scanning electron microscopy. Reactions occurred at 660 A degrees C on bare Si and at ca. 690 A degrees C on the SiO2 layer. However, the SiO2 did not withstand annealing at higher temperatures. The SiNX layer showed no Al-BSF region in samples annealed at up to 760 A degrees C, making it a suitable material for rear passivation layers in local contact Si solar cells. A Si solar cell fabricated by laser drilling and screen printing showed an efficiency of 12.41% without optimization.

• 出版日期2012-8