Interaction of vacuum ultraviolet excimer laser radiation with fused silica: II. Neutral atom and molecule emission

Journal Article · Mon Feb 15 00:00:00 EST 2010 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3290879· OSTI ID:21476119

George, Sharon R; Langford, S C; Dickinson, J T ^[1]

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1. Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)

We report mass-resolved time-of-flight measurements of neutral Si, O, and SiO from ultraviolet-grade fused silica during pulsed 157-nm irradiation at fluences well below the threshold for optical breakdown. Although the emission intensities are strongly affected by thermal treatments that affect the density of strained bonds in the lattice, they are not consistently affected by mechanical treatments that alter the density of point defects, such as polishing and abrasion. We propose that the absorption of single 157 nm photons cleave strained bonds to produce defects that subsequently diffuse to the surface. There they react with dangling bonds to release neutral atoms and molecules. Hartree-Fock calculations on clusters containing these defects support the contention that defect interactions can yield emission. More direct emission by the photoelectronic excitation of antibonding chemical states is also supported.

• OSTI ID: 21476119
• Journal Information: Journal of Applied Physics, Vol. 107, Issue 3; Other Information: DOI: 10.1063/1.3290879; (c) 2010 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
36 MATERIALS SCIENCE
ATOMS
DIFFUSION
EMISSION
EXCIMER LASERS
EXCITATION
HARTREE-FOCK METHOD
MASS SPECTRA
MOLECULES
OXYGEN
POINT DEFECTS
PULSED IRRADIATION
SILICA
SILICON
SILICON OXIDES
SURFACES
TIME-OF-FLIGHT METHOD
ULTRAVIOLET RADIATION
APPROXIMATIONS
CALCULATION METHODS
CHALCOGENIDES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY-LEVEL TRANSITIONS
GAS LASERS
IRRADIATION
LASERS
MINERALS
NONMETALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
RADIATIONS
SEMIMETALS
SILICON COMPOUNDS
SPECTRA