Quantitative evolution of vacancy-type defects in high-energy ion-implanted Si: Au labeling and the vacancy implanter

In ion implantation related research in Si, the role of interstitial cluste rs in dopant diffusion is fairly well understood. But there is relatively p oor understanding of vacancy clusters, mainly due to the inadequacy of pres ent techniques to profile and especially to count vacancy defects. Recently , two important steps have been taken in the direction of understanding the vacancy-type defects. The first is the demonstration that high-energy ion implantation (HEI) can be used as a vacancy implanter to introduce vacancie s (V) in Si that are separated from the interstitials (I) by relying on spa tial separation of the Frenkel pairs due to the average forward momentum of the recoils. The second is the development of two techniques, Au labeling and cross-section X-ray microbeam diffuse scattering which permit quantitat ive measurements of the vacancy-type defect clusters and their depth distri bution. In this work we highlight the Au labeling technique and use the vac ancy implanter in conjunction with Au labeling to study the evolution of ex cess vacancy defects (V-ex) created by HEI of Si+ in Si(1 0 0) as a functio n of fluence and temperature. We show that a precise injection of V-ex is p ossible by controlling implanted fluence. We also show that the V-ex cluste rs formed by the HEI are extremely stable and their annihilation is governe d by interstitial injection rather than vacancy emission in the temperature range of 800-900 degreesC. (C) 2001 Elsevier Science B.V. All rights reser ved.