Dissociation of iron-related centers in Si stimulated by hydrogen

The interaction of hydrogen with Fe-related centers in p-type Si was invest igated by deep level transient spectroscopy (DLTS). After wet chemical etch ing (WCE) of iron diffused Si samples the interstitial iron concentration e xceeds the equilibrium concentration close to the surface. The iron depth p rofiles exhibit an exponential dependence with a characteristic length iden tical to the hydrogen penetration depth, which is about ten times larger th an the iron diffusion length. On the other hand, after reverse: bias anneal ing (RBA) the iron profile deviates clearly from the exponential distributi on. Our results give evidence for a release of iron by a hydrogen-stimulate d dissociation of iron-related defects. (C) 2000 Elsevier Science S.A. All rights reserved.