Influence of gate dielectric property on the capacitance dispersion in organic-metal-insulator-semiconductor capacitors

Abstract

The capacitance dispersion with frequency in an organic-metal–insulator-semiconductor capacitor (OMISCAP) is a vital phenomenon for predicting high-frequency applications. In this paper, the influence of the dielectric constant on the capacitance dispersion of OMISCAP is investigated by varying the dielectric constant of poly-4-vinyl-phenol using cross-linker concentration. The cut-off frequency of capacitance dispersion f c at which the capacitance drops by 10% of the plateau is introduced to measure the capacitance dispersion and the range of operating frequency. The variation of f c from 34 kHz to 50 kHz upon changing the dielectric constant of the insulator from 3.8 to 4.8 appears to be due to the combined effect of the capacitance variation in step with dielectric constant and the resistance variation due to field-induced charge accumulation in the semiconductor. The experimental results are validated using TCAD simulation and parameter extraction.