Nickel Interaction with Vacancy‐Type Radiation Defects in Silicon

Abstract

The deep‐level spectrum of silicon irradiated with high‐energy electrons is modified by room‐temperature nickel in‐diffusion. Two types of Si samples are compared: The oxygen‐lean floating‐zone (FZ) and the oxygen‐rich Czochralski‐grown (Cz) crystals where the dominant vacancy‐type radiation defects are the vacancy–phosphorus (VP) and the vacancy–oxygen (VO) pairs, respectively. Both types of Ni‐diffused samples exhibit similar deep‐level spectra: The DLTS signatures of the VP and VO centers are totally converted into a novel peak at ≈180 K. Detailed Laplace‐DLTS studies show that the complexes formed in the FZ‐ and Cz‐Si are however different: The electron emission rates from the nickel‐related centers exhibit unequal activation energies (0.35 eV for NiVP in FZ‐Si and 0.37 eV for NiVO in Cz‐Si) and demonstrate quantitatively differing responses to the electric field. The origin for the similarity of the NiVP and NiVO complexes is discussed.