Capapitance-voltage characteristics of Al/SiO2/Si structures with embedded Si nanocrystals

Here we present our investigations on Al/SiO₂/Si structures with Si nanocrystals embedded into the oxide layer. Nanocrystals were formed by implantation of Si ions with following high temperature annealing in N₂ ambient. Capacitance-voltage characteristics (C-V) were measured at frequencies varied from 1 to 145 kHz at room temperature. Maximum in capacitance characteristics was observed at voltages corresponding accumulation condition at near surface area of semiconductor. Such features are usually explained by discrete level of surface states. The maximum capacitance amount and its correlation with capacitance value at accumulation conditions were found to depend on frequency.