Interactions of wide band gap single crystals with 248 nm excimer laser radiation. III. The role of cleavage-induced defects in MgO

Journal Article · Wed Sep 15 04:00:00 EDT 1993 · Journal of Applied Physics; (United States)

DOI:https://doi.org/10.1063/1.354489· OSTI ID:6261322

Dickinson, J T; Jensen, L C; Webb, R L; Dawes, M L; Langford, S C ^[1]

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

When single-crystal, arc-fused MgO is cleaved and exposed to single pulses of 248 nm, 3--10 J/cm[sup 2] excimer laser light (in vacuum), micron-sized holes are produced in the irradiated area. Cleavage produces micron-sized sites which exhibit highly localized absorption, resulting in decomposition, melting, and vaporization of the crystal at these sites. At fluences between 1 and 2 J/cm[sup 2], single laser pulses can produce localized, superficial melting and decomposition, leaving clusters of Mg-rich droplets on the surface. The mass-resolved charged and neutral particle emission produced by irradiation of the cleaved MgO surface with single laser pulses are examined. There are considerable variations in these emissions when single laser pulses strike different regions of the cleavage surface; these variations are strongly correlated with the production of conical holes in the irradiated region. A phenomenological model for the creation of these sites involving dislocation driven processes during cleavage and the resulting interactions of these sites with the laser beam are presented.

• DOE Contract Number: FG06-92ER14252
• OSTI ID: 6261322
• Journal Information: Journal of Applied Physics; (United States), Journal Name: Journal of Applied Physics; (United States) Vol. 74:6; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360605* -- Materials-- Radiation Effects
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
CLEAVAGE
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
CRYSTALS
DISLOCATIONS
ELECTROMAGNETIC RADIATION
EVAPORATION
HEATING
HOLES
LASER-RADIATION HEATING
LINE DEFECTS
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
MASS SPECTROSCOPY
MELTING
MICROSTRUCTURE
MONOCRYSTALS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL RADIATION EFFECTS
PLASMA HEATING
RADIATION EFFECTS
RADIATIONS
SPECTROSCOPY
ULTRAVIOLET RADIATION