Spectroscopic study of beta-SiC prepared via PLD at 1064 nm

The physical properties of the wide band-gap beta-SiC make it a promising material for future applications in high-power, high-temperature and high-frequency devices. Up to now, SiC has been successfully employed in field effect transistors, bipolar storage capacitors and ultraviolet detectors. In this work, we present new attempts to prepare crystalline beta-SiC at 650 degrees C by means of Pulsed Laser Deposition (PLD). X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) have been used to determine the crystalline and morphological properties of the deposited beta-SiC thin films grown on different substrates: sapphire and silicon. The optical constants in the visible range and the band gap energy have been determined by Spectroscopic Ellipsometry (SE) which is a powerful non-destructive technique for high accuracy measurements. SiC thin films deposited on sapphire give rise to hetero-epitaxial growth resulting in an organized structure while the sample deposited on silicon grows polycrystalline. The correlation between the band-gap energy and the crystalline phases and growth conditions will be discussed.