DESIGN AND FABRICATION OF METAL-POLYMER BASED CORE-SHELL ARTIFICIAL NANODIELECTRICS FOR CAPACITOR APPLICATIONS

The need for high storage capacitors led to the development of polymer based capacitors. The permittivity of the polymer as well as its dielectric strength can be tuned to desired characteristics by introducing either ceramic or metal nano fillers. Usage of ceramic fillers would need higher loading, leading to less flexibility and compatibility with printed circuit boards. Thus metal nano fillers can be used effectively to enhance the dielectric properties. My thesis work involves loading of Silver (Ag) and Ag@SiO2 nano particles by dispersing them in a Polyvinyl Pyrrolidone (PVP) matrix. This nano composite solution acts as a dielectric for a parallel plate polymer capacitor. The capacitance and the thickness of the film were measured in order to determine the K value of the dielectric. The capacitor parameters such as the dissipation factor and breakdown voltages were also determined. The dielectric constant of PVP increased from 7 to 40 at 0.08% loading of silver nano particles. Effective medium theories and percolation theories were implemented to analyze the theoretical value of effective dielectric constant. Finite Element Method based simulations were used to study the electric field and polarization patterns inside the dielectric.