Fabrication of Thin Silicon Sheets for Solar Cells Using the Spin Casting Method

Abstract

Fabrication of thin silicon sheets via spin casting is investigated for its potential use in a kerf-free wafer production process. To reduce silicon usage and understand the melt spreading process, numerical simulation of spin casting was performed. The simulation showed a specific initial droplet velocity is required to spread small amounts of liquid, and subsequent experiments confirmed this prediction. The increase in initial droplet velocity enabled the reduction in the spreading time and allowed the liquid melt to be spread fully before solidification began. Using a rotating graphite mold, silicon sheets of 100 mu m thickness can be produced under optimized experimental conditions.