GROWTH AND CHARACTERIZATION OF SILICON THIN-FILMS EMPLOYING SUPERSONIC JETS OF SIH4 ON POLYSILICON AND SI(100)

Supersonic jets of silane were employed to deposit silicon on both pol ysilicon and Si(100) at substrate temperatures ranging from 500 to 650 degrees C. The growth rate and film uniformity were studied as a func tion of silane kinetic energy. Increasing the SiH4 precursor kinetic e nergy from 0.4 eV (10% SiH4 in He mixture) to 1 eV (1% SiH4 in H-2 mix ture) results in as much as an order of magnitude increase in reaction probability. The advantage of using high kinetic energy precursors to enhance deposition is reflected in the centerline growth rates obtain ed employing supersonic jets of SiH4. At higher substrate temperatures , the high kinetic energy SiH4 jet has a higher growth rate than the l ow kinetic energy SiH4 jet, although, the flux of the high energy jet at the centerline is a factor of 8 less than the flux of the low energ y jet. The silane flux distribution from the supersonic jet is depende nt on the gas mixture; a flux distribution of Cos(55) theta results fr om the 1% silane in hydrogen jet (1 eV) compared to a Cos(28) theta di stribution from the 10% silane in helium jet (0.4 eV). (C) 1997 Americ an Institute of Physics.