Capacitance-voltage (C-V) measurements of the as-deposited (AD) and the annealed (ann) samples under different frequencies. Frequencies: 100 Hz, 1 kHz, 10 kHz, 100 kHz, and 1 MHz. Remarkable frequency dispersions on C-V curves are observed for both the as-deposited (a) and the annealed samples (b). Compared to the as-deposited samples, the annealed samples show pronounced accumulation capacitance reduction. The most important effect of annealing is related to weakened accumulation capacitance and hence reduced k-value.
Zhao et al. Nanoscale Research Letters 2013 8:172 doi:10.1186/1556-276X-8-172