Microstructural and electrical properties of Pb(Zr0.52Ti0.48)O3 films grown on p-InSb (111) substrates at low temperature Original Research Article

Ferroelectric Pb(Zr0.52Ti0.48)O3 thin films were grown on p-InSb (111) substrates by using a radio-frequency magnetron sputtering method at low temperature (∼350°C). Atomic force microscopy (AFM) and X-ray diffraction (XRD) measurements showed that the Pb(Zr0.52Ti0.48)O3 film layers grown on InSb substrates were polycrystalline thin films with smooth surfaces, and Auger electron spectroscopy (AES) measurements indicated that the compositions of the as-grown films consisted of lead, zirconium, titanium and oxygen. Transmission electron microscopy (TEM) and selected-area electron diffraction measurements showed that the grown Pb(Zr0.52Ti0.48)O3 was a polycrystalline layer with small domains and that the Pb(Zr0.52Ti0.48)O3/InSb (111) heterointerface had no significant interface problems. Room-temperature current–voltage and capacitance–voltage (C–V) measurements clearly revealed a metal-insulator–semiconductor behavior for the Pb(Zr0.52Ti0.48)O3 insulator gates, and the interface state densities at the Pb(Zr0.52Ti0.48)O3/p-InSb interfaces, as determined from the C–V measurements, were approximately high 1011 eV−1 cm−2 at the middle of the InSb energy gap. The dielectric constant of the Pb(Zr0.52Ti0.48)O3 thin film, as determined from the C–V measurements, was as large as 803.2. These results indicate that the Pb(Zr0.52Ti0.48)O3 layers grown on p-InSb (111) substrates at low temperatures can be used both for high-density dynamic memories and high-speed varistors based on InSb substrates.