Structural and electrical properties of Pb(Zr,Ti)O3 thin films on GaN/Sapphire, Ru/Sapphire and Ru/GaN/Sapphire substrates

Lead zirconate titanate or Pb(Zr0.3Ti0.7)O-3 thin films were deposited on GaN, Ru/Sapphire and Ru/GaN/Sapphire substrates by the sol-gel technique. The Ru films, with a (002) preferred orientation, were deposited by metalorganic chemical vapor deposition (MOCVD) on Sapphire (0001) and GaN/Sapphire substrates. The properties of PZT on Ru films, rapid thermal annealed under different conditions, are investigated. The P-E hysteresis curves and C-V data for PZT films on Ru/GaN and Ru/Sapphire substrates were measured as a function of voltage and frequency. The Metal-Ferroelectric-Semiconductor (MFS or Pt/PZT/GaN) structures, prepared by depositing PZT thin films on n-type (Si doping similar to1 x 10 18 cm(-3)) and (0001)-GaN/Sapphire, were characterized for their dielectric properties. The PZT films on as-deposited Ru, as opposed to annealed Ru, exhibit improved properties; remnant polarization of 37 muC/cm(2) , dielectric permittivity of 425 at 100 KHz, and leakage current density similar to1 x 10(-7) A/cm(2) at 1.5 V.