Alpha-Sic-Beta-Sic Heteropolytype Structures On Si (111)

Nanoscale alpha-SiC(0001) on beta-SiC(111) heterostructures on Si (111) substrates fabricated by ultralow-pressure chemical vapor deposition are demonstrated. The intentional formation of the alpha-beta structure was achieved by adjusting the SiH4 to C2H4 flux ratios to carbon rich conditions and by controlling the diffusion length. The developed method allows the formation of heteropolytypic structures with a controlled thickness of the intermediate cubic beta-SiC layer. (C) 2005 American Institute of Physics.