A comprehensive study on the interface states in the ECR-PECVD SiO2/p-Si MOS structures analyzed by different method

Abstract The electrical properties of SiO 2 /p-Si films deposited by ECR-PECVD s were studied at different frequencies (100-1 MHz) and gate voltages (−6–3 V). Results showed a frequency dispersion of C-V g and G/ω-V g . With increasing frequency, the capacitance and conductance are strongly decreased. An apparent peak in the depletion regime of the G/ω-Vg plots can be attributed to the existence of density N ss at Si/SiO 2 . The (N ss )value vary from 1.5 × 10 12 to 0.5 × 10 11  eV −1  cm −2 , it has been determined by High-Low frequency capacitance technic. The N ss - V g curve presents a peak at about −3 V, suggesting the presence N ss between the (Si)/SiO 2 interface. Hill and Coleman method shows that the N ss decreases with increasing frequency which explains the high value of capacitance at low frequency. The N ss and their relaxation time τ by the conductance method ranged from 1.8 × 10 13 to 1.37 × 10 11  eV −1  cm −2 and 5.17 10 −7 to 8 × 10 −6  s, in the range (0.189-E v ) and (0.57- E v ) eV, respectively. The N ss was responsible for the non-ideal behavior of C-V g and G-V g leading to the breakdown of such device. Comparing the three method results show that parallel conductance is very precise and accurate.