Epitaxial growth of TiC on (0001) 4H-SiC substrate by reactive sputtering

Abstract

Heteroepitaxial TiC films were grown on semi-insulating (0001) 4H-SiC substrates at high temperature by using direct current (DC) magnetron reactive sputtering. The effect of the CH4 flux ratio in Ar on the crystalline quality of the films was investigated. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that the deposited TiC films are heteroepitaxially grown on 4H-SiC substrates with the heteroepitaxial relationship between TiC and 4H-SiC in (111)TiC // (0001)4H-SiC and [11¯0]TiC // [112¯0]4H-SiC. The full width at half-maximum (FWHM) of X-ray rocking curve (XRC) of (111)TiC reflection can reach a minimum value of 0.039° and the resistivity of TiC film can be ∼ 80 μΩ⋅cm for deposition at 700 °C with 4% CH4 flow ratio. X-ray photoelectron spectroscopy (XPS) shows that the composition of TiC film is nearly in stoichiometry for 4% CH4 flow ratio. From the TEM results, it is observed that the TiC film is divided into a strained layer and a relaxed layer when the film thickness reaches a critical value over about 70 nm.