Material and electrical characterizations of high-k Ta₂O₅ dielectric material deposited on polycrystalline silicon and single crystalline substrate

Samples of high-k Ta₂O₅ film as a high-k gate dielectric sputtered on both a single crystalline substrate and a polycrystalline silicon substrate and annealed at different temperatures were fabricated and compared. Samples were examined using various material and electrical analyses, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force spectroscopy (AFM), equivalent oxide thickness (EOT), JE characteristics, charge-to-breakdown Weibull plots, and gate voltage shift versus stress time. The research concludes that a Ta₂O₅ dielectric on a single crystalline substrate had fewer structural defects than a high-k/polysilicon interface, forming a dielectric with better material properties and electrical reliability.