Finite Element Simulation of Inkjet Printed Flexible Parallel Plate MIM Capacitors on Polyimide Film

Abstract

As the potential usage of flexible electronics inkjet printing (IJP) is rapidly growing in flexible electronics, we present a Finite Element Analysis (FEA) with electrostatic modeling of a Metal-Insulator-Metal (MIM) type parallel plate capacitor using COMSOL Multiphysics designed for application in flexible electronic circuits. In this study, silver was used as the conductive metal parallel plates and Poly(4-vinylphenol) (PVP) was used as the insulator material. We compared our simulated result with IJP parallel plate capacitors where the bottom and top plate was printed with JS B40 silver ink and dielectric layer was printed with PVP dielectric ink. We also compared our simulation results with ideal calculated capacitance values. Our simulated results are promising and matched closely with the calculated and experimental results from fabricated capacitances. We demonstrated the change of capacitance due to variance of design parameters, such as, the area of the capacitance. Our printed IJP capacitors provided us the capacitance in the range of 8.8 pF to 467 pF for capacitor area 1 to 36 mm, while the simulated capacitance range was recorded between 9 pF to 455 pF. For four coat PVP the minimum and maximum capacitance obtained from simulations were 13.3 pF and 455 pF for capacitor area 1 mm2 and 36 mm2 respectively. The simulated capacitances with six coat PVP were 9 pF and 310 pF for 1 mm2 and 36 mm2 capacitor area respectively. For flexible electronics devices like body-worn sensors, IJP electronic components will be significant in near future and this paper lays the key foundation for that endeavor.