Effect of low fluence laser annealing on ultrathin Lu2O3 high-k dielectric

Abstract

The effect of low fluence single pulse laser annealing on a pulsed laser deposited high-k dielectric, Lu2O3 is reported. With low fluence laser irradiation, high “k” of 45 is achieved with an equivalent oxide thickness of 0.39nm, without taking into account the quantum mechanical tunneling effect. High-resolution transmission electron microscopy micrograph revealed well-ordered epitaxial-like interfacial layer. High-resolution Rutherford backscattering confirmed the presence of Lu-based silicate layer at the interface. It was proposed that the high dielectric constant was caused by the increased ionic polarizability in the film, thereby increasing the ionic contribution of the dielectric constant.