Exploring the limits of low cost, organics-compatible high-k ceramic thin films for embedded decoupling applications

This paper presents four organic-compatible thin film processing techniques for embedding capacitors into organic PWBs. Hydrothermal synthesis allows integration of pure nano-grained barium titanate films with capacitance density of about 1 μF/cm². Sol-gel and RF-sputtering in conjunction with a foil transfer process can be used to integrate a variety of perovskite thin films with the capacitance in the range of 200-400 nF/cm². Thermal oxidation of titanium foil also emerges as a viable process for integrating capacitance of 100s of nF using a foil transfer process. The dielectric properties of the films synthesized by these techniques as a function of various process parameters are presented. Observed dielectric properties like dielectric constant, leakage current and breakdown strengths have been correlated to structural defects and stoichiometry of the films.