Simulation Analysis and Experimental Research on the Fracture Strength of Photovoltaic Monocrystalline Silicon Slicing Wafers

Abstract

Abstract: Monocrystalline silicon is widely used in the photovoltaic industry. As the thickness of wafer processing gradually decreases and the wire saw diameter becomes smaller, phenomena such as adhesion during the slicing process lead to bending or even breaking of the photovoltaic monocrystalline silicon slices, which in turn increases the breakage rate and significantly impacts the cost of photovoltaic solar cells. This study focuses on the cutting process of photovoltaic monocrystalline silicon wafers, using a three-axis bending experiment to measure and analyze the fracture strength and corresponding breakage rate of the silicon wafers. A three-dimensional simulation analysis model for the fracture strength of the silicon slicing wafers was established by finite element method. The research results show that the fracture strength of the silicon slicing wafers has a large dispersion, the average fracture strength is 97.7 MPa. The bending stiffness of the silicon slicing wafers decreases as the thickness decreases, with an average bending stiffness of 441.2 N/m. When the thickness is 60 μm, the bending stiffness is the lowest at 103.5 N/m. The range of wafer breakage rate increases with the decrease of thickness, and the range of wafer breakage rate of 60 μm thickness is the largest, ranging from 0.6% to 99.9%. Simulation and experimental results are basically consistent, indicating that the simulation model and method are suitable for the simulation and analysis of the fracture strength and breakage rate of photovoltaic monocrystalline silicon slices.

Key words: photovoltaic monocrystalline silicon, slicing process, fracture strength, finite element analysis, thickness, breakage rate

CLC Number:

O786
TG58

TAN Huiying, XING Xu, GE Peiqi, BI Wenbo. Simulation Analysis and Experimental Research on the Fracture Strength of Photovoltaic Monocrystalline Silicon Slicing Wafers[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(8): 1369-1377.

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