AVS 53rd International Symposium
    Surface Science Thursday Sessions
       Session SS-ThP

Paper SS-ThP12
Photoemission Analysis with Synchrotron Radiation for Nitridation of SiO@sub 2@ Thin Film on Si(001) by Irradiation of N@super +@ Ion Beams

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: Surface Science Poster Session
Presenter: Y. Teraoka, Japan Atomic Energy Agency
Authors: Y. Teraoka, Japan Atomic Energy Agency
S. Hachiue, Kobe University, Japan
K. Yokota, Kobe University, Japan
M. Tagawa, Kobe University, Japan
Correspondent: Click to Email
Energetic atomic and molecular beams are useful for modification of ultra-thin layers in ULSI devices.  The silicon dioxide overlayers on Si(001) substrates were fabricated by a rapid thermal oxidation (RTO) method.  The thickness was ranging from 1.6 nm to 2.8 nm, which was estimated by ellipsometry. Nitrogen gas was discharged in a PIG-type cold-cathode plasma ion source.  The ions generated in the ion source were extracted and accelerated up to a translational kinetic energy of 3 keV and focused by a pair of Einzel lens.  The atomic nitrogen ions were separated from other ionic species by using a Wien filter (E x B separator).  The mass-selected atomic nitrogen ion beams were decelerated and irradiated at the ultra-thin silicon dioxide overlayers on Si(001) substrates by 6.3x10@super 15@ to 2.0x10@super 16@ particles/cm@super 2@ at room temperature.  Chemical bonding states of Si, O, and N atoms in the nitrogen-impinged region were analyzed via photoemission spectroscopy using high brilliance and energy-resolution synchrotron radiation of 688 eV after transferring the samples from the ion beam apparatus to the photoemission apparatus.  Photoemission spectra of N-1s core level could be observed in addition to Si-2p and O-1s peaks owing to the high brilliance synchrotron radiation.  It was found that the silicon dioxide overlayer and the interface were effectively nitrided even by the dose of 10@super 15@ particles/cm@super 2@ order as well as the Si(001) substrate.  N-1s photoemission spectra were asymmetric and deconvoluted into four components.  Consequently, they were assigned to (a) N(-Si)@sub 3@, (b) N(-SiO@sub 3@)@sub 3@, (c) SiN@sub 3@-NO-SiN@sub 2@O, and (d) O-N(-Si)@sub 2@, respectively.