A DEEP-LEVEL TRANSIENT SPECTROSCOPY CHARACTERIZATION OF DEFECTS INDUCED IN EPITAXIALLY GROWN N-SI BY LOW-ENERGY HE-ION BOMBARDMENT

Epitaxially grown n-Si was bombarded with low-energy (1 keV) He ions. Deep level transient spectroscopy revealed that this introduced four p rominent defects with energy levels at 0.14, 0.20, 0.30, and 0.55 eV, respectively, below the conduction band. The electronic properties and annealing behavior of these defects are different to those of the mai n defects, namely, divacancies (V-2) and vacancy-phosphorous centers, observed after 5.4 MeV He-ion bombardment of the same material. We pro pose that, except for the defect with an energy level at E-c-0.14 eV, the defects introduced by 1 keV He-ion bombardment of n-Si may be rela ted to: (1) vacancy clusters larger than divacancies, or (2) incorpora tion of He and H into V-2 or higher-order vacancy clusters. (C) 1998 A merican Institute of Physics.