Gamma irradiation effects on Al/n-Si Schottky junction properties

In this paper the gamma irradiation effects on the structural and electrical properties of n-Si and Al/n-Si Schottky junctions are presented up to a cumulative radiation dose of 1500 kGy. The structural studies using XRD and Raman spectroscopic techniques showed no greater degradation in the crystallinity of the n-Si crystals due to the irradiation effects. However, considerable variations in the I-V characteristics of Al/n-Si Schottky junctions and its junction parameters such as Schottky barrier height (Phi(B)), ideality factor (n) and series resistance (R-s) indicates the presence of gamma induced defect states in the interface as well as bulk of the crystal. The surface and interface analysis of the irradiated Al/n-Si Schottky junction revealed modification in the effective work function of Al and presence of different chemical states (AlOx-SiOx) in the interface. The contribution of these interface trap states on the band bending properties and I-V characteristics are explained in detail by realizing the power law characteristics and energy band diagram of the Al/n-Si Schottky junction.