초고온 MEMS용 단결정 3C-SiC의 Ohmic Contact 형성

Abstract

This paper describes the ohmic contact formation of single crystalline 3C-SiC thin films heteroepitaxially grown on Si(001) wafers. In this work, a TiW (Titanium-tungsten) film as a contact matieral was deposited by RF magnetron sputter and annealed with the vacuum and RTA (rapid thermal anneal) process respectively. Contact resistivities between the TiW film and the n-type 3C-SiC substrate were measured by the C-TLM (circular transmission line model) method. The contact phases and interface the TiW/3C-SiC were evaulated with XRD (X-ray diffraction), SEM (scanning electron microscope) and AES (Auger electron spectroscopy) depth-profiles, respectively. The TiW film annealed at <TEX>$1000^{\circ}C$</TEX> for 45 sec with the RTA play am important role in formation of ohmic contact with the 3C-SiC substrate and the contact resistance is less than <TEX>$4.62{\times}10^{-4}{\Omega}{\cdot}cm^{2}$</TEX>. Moreover, the inter-diffusion at TiW/3C-SiC interface was not generated during before and after annealing, and kept stable state. Therefore, the ohmic contact formation technology of single crystalline 3C-SiC using the TiW film is very suitable for high temperature MEMS applications.