Separation of vacancy and interstitial depth profiles in ion-implanted silicon: Experimental observation

An experimental concept of studying shifts between concentration-versus-depth profiles of vacancy and interstitial-type defects in ion-implanted silicon is demonstrated. This concept is based on deep level transient spectroscopy measurements where the filling pulse width is varied. The vacancy profile, represented by the vacancy-oxygen center, and the interstitial profile, represented by the substitutional carbon-interstitial carbon pair, are obtained at the same sample temperature and can be recorded with a high relative depth resolution. For 6 MeV ¹¹B ions, the peak of the interstitial profile is displaced by ∼0.5 μm towards larger depths compared to that of the vacancy profile, which is primarily attributed to the preferential forward momentum of recoiling Si atoms.