Defect identification using the core-electron contribution in Doppler-broadening spectroscopy of positron-annihilation radiation

Reduction of background using a coincidence-detection system in Doppler-broadening spectroscopy of positron-annihilation radiation allows us to examine the contribution of high-momentum core electrons. The contribution is used as a fingerprint to identify chemical variations at a defect site. The technique is applied to study a variety of open volume defects in Si, including decorated vacancies associated with doping. {copyright} {ital 1996 The American Physical Society.}