| In this work, effects of strain and stress in heterostructures consisting of a few nanometers thin 3C-SiC films have been studied. Advances in epitaxial growth technology have enabled the development of high-quality thin film materials. Thin 3C-SiC films exhibit significantly different electrical behavior than the bulk material or the substrate itself, giving rise to a potential use of nano-thin films as surface sensors. In order to investigate the properties of thin film structures, nano-thin 3C-SiC layers were grown on n-type silicon substrates by Gas Source Molecular Beam Epitaxy (GSMBE). Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) characterizations were performed to analyze the crystalline quality and the surface of the growth films. Reflection High-Energy Electron Diffraction (RHEED) patterns obtained from several 3C-SiC films grown using dimethyl silane show that these films are about 3% strained relative to the SiC lattice constant. Al, Cr and Pt contacts to a nano-thin film 3C-SiC were deposited and characterized. Experimental I/V measurements on the strained nano-thin films demonstrate Metal-Semiconductor-Metal (MSM) characteristics. Band offsets due to biaxial tensile strain introduced within the 3C-SiC films were calculated and band diagram applying strain effects have been simulated. Eventually, based on the experimental measurements and simulation results, an empirical model for the current transport in the heterostructures designed based on strained nano-thin films has been proposed. |
