SPATIAL DISTRIBUTION OF WAFER SUBSURFACE DAMAGE INDUCED BY WIRE SAWING

摘要

The goal of this paper is to investigate the distribution of saw damage on the wafer after slurry based multi-wire sawing of silicon ingots. Roughness and crack depth distributions were determined at different positions on the wafer surface. From these parameters the size distribution of single chipping events by the abrasive SiC particles in the slurry can be estimated. Furthermore the influence of the sawing conditions on roughness and crack depth distributions were studied. From our results we conclude that both roughness and crack depth distributions correlate to the model of rolling and indenting abrasive particles. Additionally our experimental findings support the conception of successively flushing abrasive particles out of the cut zone under the wire. In particular the fraction of the biggest SiC particles in the particle size distribution leaves the cut zone from wire inlet to wire outlet.