Nickel and platinum ohmic contacts to polycrystalline 3C-silicon carbide

Nickel and platinum contacts to n-type doped polycrystalline 3C-SiC (poly-3C-SiC) were characterized by the circular transmission line method (CTLM) at room temperature and 300 deg. C. The poly-3C-SiC films were deposited at 800 deg. C using 1,3-disilabutane single precursor in a low-pressure chemical vapor deposition (LPCVD) reactor, and were in situ nitrogen doped using NH3. Nickel contacts to poly-3C-SiC showed ohmic characteristics at room temperature, with contact resistivity varying with the doping content of poly-3C-SiC films and reaching the minimum value of 1.6 x 10-6 Ω cm2. The contact resistivity increased to 1.3 x 10-5 Ω cm2 after the contact was annealed at 300 deg. C in air. Platinum contact to poly-3C-SiC was also ohmic with an as-deposited contact resistivity of 1.2 x 10-5 Ω cm2, but better thermal stability. A stable ohmic contact at 300 deg. C was achieved with a contact resistivity of about 3.6 x 10-5 Ω cm2 on Pt contacts to poly-3C-SiC films