GROWTH AND CHARACTERIZATION OF THIN SI80C20 FILMS BASED UPON SI4C BUILDING-BLOCKS

The growth of thin Si80C20 diamond-structured material on (100)Si has been achieved using the novel C-H free, carbon source tetrasilyl metha ne, C(SiH3)(4). The precursor decomposes at temperatures in the range 600-700 degrees C to give thin amorphous layers with a composition of Si0.80C0.20, which corresponds to the same relative concentrations of Si and C as in the precursor. The amorphous material is crystallized v ia solid-phase epitaxy by annealing at 825 degrees C to yield a potent ially ordered structure in which Si4C tetrahedra are linked together i n a three-dimensional diamond-cubic framework. Measured lattice parame ters are larger than expected from Vegards' Law, a discrepancy which i s attributed to steric repulsions causing bond elongation. (C) 1998 Am erican Institute of Physics.