Electrical characterization of n-type polycrystalline 3C-silicon carbide thin films deposited by 1,3-disilabutane

X-ray diffraction, Hall effect probe, and four-point probe were used to characterize the n-type doping of polycrystalline 3C - SiC (poly-SiC) thin films. The films were deposited at 800 degrees C on SiO2-isolated Si(100) substrates by low-pressure chemical vapor deposition using 1,3-disilabutane single precursor and ammonia. Resistivity values as low as 30 m Omega cm were achieved. A shrinkage in the SiC lattice constant from 4.360 to 4.345 angstrom was observed upon doping. The carrier concentration increased with doping from 9.2 x 10(15) to 6.8 x 10(17) cm(-3), while mobility decreased from 2063 to 400 cm(2)/V s. The temperature coefficient of resistivity was characterized in the range of 304 - 638 K and decreased in magnitude with temperature from - 2.4 to - 1.3% K-1 for undoped and - 0.17 to - 0.10% K-1 for the most conductive samples. The crystalline quality, carrier concentration and mobility, and energy barrier height at grain boundaries are discussed and correlated to the observed resistivity variation with doping. (C) 2006 The Electrochemical Society.