Chen, WM;McNally, PJ;Shvydko, YV;Tuomi, T;Lerche, M;Danilewsky, AN;Kanatharana, J;Lowney, D;O'Hare, M;Knuuttila, L;Riikonen, J;Rantamaki, R

2001

August

Physica Status Solidi (A) Applied Research

Quality assessment of sapphire wafers for X-ray crystal optics using white beam Synchrotron X-Ray Topography

Published

18 ()

BASAL SLIP ALPHA-AL2O3 BACKSCATTERING DEFECTS DEVICES GROWTH GAN

186

365

371

The white beam Synchrotron X-Ray Topography (SXRT) technique was used to assess the quality of sapphire wafers grown by the Heat-Exchanger Method (HEM) and the Modified Czochralski Method (MCM). Sapphire is a potential new material for X-ray crystal optics, especially for use as Bragg backscattering mirrors for X-rays and Mossbauer radiation. The dislocation distribution, dislocation density and Burgers vector of selected dislocations and stacking faults in the sapphire wafers were studied. A correlation between the sapphire quality and its performance as an X-ray backscattering mirror was established in this paper. The results reveal the high quality of the inspected HEM sapphire wafers and their subsequently improved performance as Bragg backscattering mirrors.

BERLIN

0031-8965