Single Molecule Source Reagents for Chemical Vapor Deposition of B-Silicon Carbide.

摘要

Phase I conclusively showed the feasibility of rational design of single molecule-source reagents that could lead to improvements in the chemical vapor deposition of stoichiometric Beta silicon carbide. Four single molecule sources were synthesized, their decomposition pathways studied, and their utility in Beta-silicon carbide CVD investigated. Dramatic differences in the CVD process resulted from small changes in the reagent structure. A strained cyclic molecule, 1,3-disilacyclobutane, allowed growth of a Beta-silicon carbide film at a temperature >300 deg C lower than was possible with a similar straight chain reagent. Furthermore, the highest quality film was grown from the analogous chlorinated cyclic source reagent: 1,1,3,3 tetrachloro-1,3-disilacyclobutane. We propose that decomposition of the cyclic precursors directly produces intermediates that can lead to deposition of stoichiometric silicon carbide. The Phase I results clearly showed that Beta-silicon carbide CVD can be improved by molecular engineering of the source reagents. Cyclic precursors are promising for both the deposition of single crystal films at high temperature and for polycrystalline and single crystal films at low temperature. In Phase II we will optimize the precursor for low temperature deposition and the integration of silicon and silicon carbide HBT device structures.