New intrinsic gettering process in silicon based on interactions of silicon interstitials

Abstract
A new intrinsic gettering process was found in silicon crystals subjected to a three-step annealing sequence. The process involves native point defects (silicon interstitials) rather than residual oxygen impurity, and thus it can be realized in crystals with low or virtually zero oxygen concentration. The key characteristics of the process (i.e., denuding and gettering efficiency and the role of annealing ambient) are discussed in conjunction with a kinetic model involving diffusion of silicon interstitials. The identity of the intrinsic gettering centers was pursued by transmission electron microscopy.