New experimental observations of single electron trapping properties of Si nanoclusters in SRO obtained by LPCVD

Abstract It has been proposed that silicon nanoclusters embedded in silicon-rich oxide (SRO) can trap one electron, or one hole. Also, it has been suggested that embedded nanoclusters can be classified into interface and bulk nanoclusters. The possibility of using the characteristic of one electron trapping property in new devices is now under intensive research. In this paper, the charging and discharging properties of silicon-rich oxide layer were studied using an Al/SRO/Si MOS-like structure. The SRO layer was deposited by low pressure chemical vapor deposition, and half of the samples were thermally annealed at 1100°C in N2 ambient. The measured I–V characteristics show clear current peaks and valleys in low voltage regime. This extraordinary behavior is ascribed to the charge exchange between the embedded nanoclusters in SRO layer and the Si substrate. The valence band of the nanoclusters is supposed to play an important role during the charging and discharging process. C–V measurements were also performed in order to clarify the results. The effect of thermal annealing was explored.