Step-Scanning WSR Section Topography for Indirect (Point Defect) Characterization of Dislocation-Free Si Wafers

Abstract

A (0.1%) variation in point defect concentration across dislocation‐free (100)‐Si‐wafers is indirectly detected from changes in (pendellösung) fringe profiles, recorded in white synchrotron radiation section topographs (WSRST's). By vertically step‐scanning each wafer across the beam more than fifty “(022)”‐images are stored on one film in a single scan, reducing both film‐development time, ‐costs, and simultaneously making more efficient use of the beam time. The method detects point defects more sensitively than those by Fourier transform IR‐ or photoluminescence‐spectroscopy.

X-ray topography studies of microdefects in silicon

“…Sample A (figure 6) is a good example in which individual images of microdefects are still recognizable. The Kato fringes are influenced by macroscopic deformations due to statistical distributions of small defects (Kato 1980;Stephenson 1990;Sugita et al . 1987;Iida et al .…”

“…, 1990Iida et al . , 1998Stephenson 1990Stephenson , 1992Li et al . 1994;Lefeld-Sosnowska 1985;Lefeld-Sosnowska et al .…”