B35 レーザ照射による多結晶シリコンウエハの欠陥修復に関する研究(OS9 レーザ応用加工(1))

Abstract

Poly-crystalline silicon wafers sliced by a wire saw have surface damage such as saw marks and microcracks, and subsurface defects such as lateral cracks, amorphous layers, and residual stresses. In this study, a pulsed Nd:YAG laser was used to recover the surface and subsurface damages in the wire sawed poly-crystalline silicon wafers. Changes in the surface topography and subsurface integrity were investigated by laser probe surface profilometer, laser Raman spectroscopy and scanning electron microscopy. The possibility of crystalline structure reconstruction and surface smoothing by the proposed laser recovery method has been demonstrated. The findings from this study may be used to reduce production cost and improve product quality of silicon-based solar cells.