A STUDY OF SILICON EPITAXIAL-GROWTH ON SILICON SUBSTRATES EXPOSED TO AR ELECTRON-CYCLOTRON-RESONANCE PLASMAS

Epitaxial growth of Si on Si(100) wafers was carried out at 700 degree s C in an Ar microwave electron cyclotron resonance plasma chemical va por deposition system. Both plasma exposure prior to growth and epitax ial growth were monitored by real-time single-wavelength ellipsometry, first to determine an optimum end point for Ar plasma cleaning which would favor quality epitaxial growth, and second to follow the growth of the epitaxial film. Spectroscopic ellipsometry combined with cross- sectional transmission electron microscopy and atomic force microscopy were used to characterize the epitaxial films, the epitaxial film/sub strate interface, and the surface morphology. Secondary-ion mass spect roscopy was used to evaluate the contamination levels st the film/subs trate interface. Epitaxial films were successfully grown on both, smoo th and rough (20-30 nm roughness layer) Si substrates. For both cases the top surface of the epitaxial film was smooth, but the interfaces w ere different. (C) 1995 American Vacuum Society.