Characterization of crystalline SiC films grown by pulsed laser deposition

Pulsed laser deposition (PLD) is well known as a reliable, economical techn ique for the growth of high-temperature superconducting oxide thin films. T here are a number of interesting characteristics, however, that distinguish this method from other thin film techniques. In particular, the vapor spec ies are typically characterized by average energies far above those encount ered in thermal evaporation and chemical vapor based approaches. As a resul t, PLD may have the potential to realize films with a smoother morphology a t low substrate temperatures if the surface species can retain some portion of the initial kinetic energy after adsorption. In this paper, we examine the PLD growth of SiC thin films on (100) silicon and (0001) sapphire subst rates over a substrate temperature range of 250-900 degrees C. In-situ char acterization using reflection high-energy electron diffraction indicates th at films deposited on sapphire above 700 degrees C, using low laser fluence , initially grow as single crystal material. X-Ray diffraction shows either 3C-SiC features or no features at all, independent of the type of substrat e. Atomic force microscopy shows very smooth films, with an average surface roughness of 3 Angstrom at a substrate temperature of 250 degrees C and 0. 7 Angstrom at 900 degrees C. (C) 2000 Published by Elsevier Science S.A. Al l rights reserved.