Effect of pulse laser frequency on PLD growth of LuFeO3 explained by kinetic simulations of in-situ diffracted intensities
Abstrakt
Atomistic processes during pulsed-laser deposition (PLD) growth influence the physical properties of the resulting films. We investigated the PLD of epitaxial layers of hexagonal LuFeO3 by measuring the X-ray diffraction intensity in the quasiforbidden reflection 0003 in situ during deposition.
From measured X-ray diffraction intensities we determined coverages of each layer and studied their time evolution which is described by scaling exponent beta directly connected to the surface roughness. Subsequently we modelled the growth using kinetic Monte Carlo simulations.
While the experimentally obtained scaling exponent beta decreases with the laser frequency, the simulations provided the opposite behaviour. We demonstrate that the increase of the surface temperature caused by impinging ablated particles satisfactorily explains the recorded decrease in the scaling exponent with the laser frequency.
This phenomena is often overlooked during the PLD growth.