Misfit Dislocation Nucleation Study in p / p + Silicon

Abstract

Different edge treatments were used during the processing of 150 mm diameter highly boron-doped silicon substrate wafers to create a variation of crystallographic damage around the wafer edges. We studied the wafer edge as misfit dislocation generation sites in epitaxial silicon wafers. These strain-relaxing defects nucleate heterogeneously at the lattice-mismatched interface. We examined the effect of a variation of wafer edge treatments on misfit dislocation formation in silicon test wafers. We determined that a lower microroughness of the wafer edge results in a decrease in the misfit dislocation density and length. We were able to show that a careful combination of edge treatments including damage removal steps helps significantly reduce misfit dislocations in strained layer epitaxy. © 2001 The Electrochemical Society. All rights reserved.