Coulomb blockade effects in silicon nanoparticles embedded in thin silicon-rich oxide films

Silicon nanoparticles (Si-nps) embedded in silicon oxide matrix were created using silicon-rich oxide (SRO) films deposited by low pressure chemical vapour deposition (LPCVD) followed by a thermal annealing at 1100°C. The electrical properties were studied using metal-oxide-semiconductor (MOS) structures with the SRO films as the active layers. Capacitance versus voltage (C-V) exhibited downward and upward peaks in the accumulation region related to charge trapping and de-trapping effects of Si-nps, respectively. Current versus voltage (I-V) measurements showed fluctuations in the form of spike-like peaks and a clear staircase at room temperature. These effects have been related to the Coulomb blockade (CB) effect in the silicon nanoparticles embedded in SRO films. The observed quantum effects are due to 1 nm nanoparticles.