Growth of SiC films via C{sub 60} precursors and a model for the profile development of the silicon underlayer
- Department of Chemical Engineering, Stanford University, Stanford, California 94305-5025 (United States)
- Chemical and Materials Science, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)
We report on an experimental and theoretical study of the growth of SiC films and of the profile development of the silicon underlayer. SiC features were grown via the direct reaction of the silicon substrate with C{sub 60} precursors. Two masking configurations were used to investigate the effects of bulk and surface diffusion on SiC film growth. Without a diffusion barrier (i.e., a patterned SiO{sub 2} mask with regions of silicon initially exposed directly to C{sub 60}), voids formed in the substrate beneath the growing SiC layer, which ultimately controlled the final thickness of the SiC film. Pronounced faceting was observed at the early stages of growth on crystalline silicon. When a tungsten diffusion barrier was used to prevent bulk diffusion (i.e., tungsten covering silicon in non-SiO{sub 2} masked regions), significant undercutting resulted beneath the oxide and SiC layers without void formation. A profile simulation was developed to model the time evolution of the silicon underlayer when this diffusion barrier is used. The simulation incorporated an adatom hopping and surface diffusion model to describe the generation and transport of silicon atoms along the evolving profile. A single fitting parameter was required. The agreement between simulation and experiment was good, and a corresponding value of the hopping coefficient was calculated. As an alternative to direct reaction with the silicon substrate, we also demonstrate experimentally that silicon atoms can be co-sublimed with fullerenes to produce SiC films on wafer surfaces, which avoids the consumption of substrate material. Co-sublimation was used to create SiC membranes and also to coat silicon microcantilevers. Force-deflection measurements for the microcantilevers revealed that the stiffness properties were enhanced with the application of a SiC film and that the co-sublimed SiC had mechanical properties like those of bulk material. {copyright} {ital 1998 American Vacuum Society.}
- OSTI ID:
- 638762
- Journal Information:
- Journal of Vacuum Science and Technology, A, Vol. 16, Issue 4; Other Information: PBD: Jul 1998
- Country of Publication:
- United States
- Language:
- English
Similar Records
Growth of silicon carbide on silicon via reaction of sublimed fullerenes and silicon
Effects of CrRu-SiO{sub x} underlayer with MgO intermediate layer on the microstructure and magnetic properties of FePt-C thin film