초고온 MEMS용 다결정 3C-SiC의 Ohmic Contact 특성

Abstract

This paper describes the ohmic contact formation of polycrystalline 3C-SiC films deposited on thermally grown Si wafers. In this work, a TiW (titanium tungsten) film as a contact material was deposited by RF magnetron sputter and annealed with the vacuum process. The specific contact resistance (<TEX>${\rho}_{c}$</TEX>) of the TiW contact was measured by using the C-TLM (circular transmission line method). The contact phase and interfacial reaction between TiW and 3C-SiC at high-temperature as also analyzed by XRD (X-ray diffraction) and SEM (scanning electron microscope). All of the samples didn't show cracks of the TiW film and any interfacial reaction after annealing. Especially, when the sample was annealed at <TEX>$800^{\circ}$</TEX> for 30 min., the lowest contact resistivity of <TEX>$2.90{\times}10{\Omega}cm^{2}$</TEX> was obtained due to the improved interfacial adhesion. Therefore, the good ohmic contact of polycrystalline 3C-SiC films using the TiW film is very suitable for high-temperature MEMS applications.