Structural, Optical and Electrical Properties of Thin Films of Lanthanum Aluminum Oxide Synthesized by Spray Pyrolysis

Abstract

The structural, optical and electrical properties of spray pyrolysis deposited lanthanum aluminum oxide are reported. The films were deposited from a spraying solutions of lanthanum nitrate and aluminum acetylacetonate in N, N- dimethylformamide using an ultrasonic generator on (100) Si substrates. The substrate temperature was in the 550-650°C range. The thickness was in below 300 Aå. The optical band gap was 5.3 eV, and the refractive index at 630 nm was up to 1.62 depending of the relation lanthanum-aluminum. The electrical characteristics of the films were determined from the capacitance and current versus voltage measurements of metal-oxide-semiconductor (MOS) structures incorporating them. A dielectric constant in the 6-12 range, interface states density of the order of 1012 X 1/eV cm2 as well as breakdown fields higher than 3 MV/cm were determine in this way.

Characterization of Lanthanum-Aluminum Oxide Thin Films Deposited by Spray Pyrolysis

“…It should be pointed out that to the best authors knowledge there are scarce reports on LA films deposited by ultrasonic spray pyrolysis in the literature. 12…”