Abstract
In the present study, the interfacial nanostructure and electrical properties of Ti3SiC2 formed by depositing a Ti–Si–C ternary film with a composition stoichiometrically equivalent to Ti3SiC2 on p-type GaN and subsequent annealing at 1073 K were analyzed by X-ray diffraction, transmission electron microscopy and direct current conduction test. The results reveal that structural changes occur by the annealing. Polycrystalline Ti3SiC2 is formed at most of the contact interface area and single crystal Ti3SiC2 at small area of the contact interface. Furthermore, other than Ti3SiC2 phase, polycrystalline Ti5Si3 and TiSi2 with different grain sizes are also formed, resulting in a formation of three-layered film after the annealing. By all these structural change, the electric conduction profiles show that the Schottky barrier height (SBH) is reduced. The estimated SBH of the Ti3SiC2 contact on p-type GaN is 0.70 eV, which is 1.73 eV lower than the theoretically predicted value.
