Structure and electrical properties of HfO2 high- k films prepared by pulsed laser deposition on Si (100)

Applied Physics A (Impact Factor: 1.69). 10/2008; 93(3):681-684. DOI: 10.1007/s00339-008-4695-8

ABSTRACT High-k gate dielectric hafnium dioxide films were grown on Si (100) substrate by pulsed laser deposition at room temperature. The
as-deposited films were amorphous and that were monoclinic and orthorhombic after annealed at 500°C in air and N2 atmosphere, respectively. After annealed, the accumulation capacitance values increase rapidly and the flat-band voltage
shifts from −1.34V to 0.449V due to the generation of negative charges via post-annealing. The dielectric constant is in
the range of 8–40 depending on the microstructure. The I–V curve indicates that the films possess of a promising low leakage
current density of 4.2×10−8A/cm2 at the applied voltage of −1.5V.

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