Optical studies during pulsed CO2 laser irradiation of ion-implanted silicon
James, R. B. ; Narayan, J. ; Wood, R. F. ; Ottesen, D. K. ; Siegfriedt, K. F.
[S.l.] : American Institute of Physics (AIP)
Published 1985
[S.l.] : American Institute of Physics (AIP)
Published 1985
ISSN: |
1089-7550
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Source: |
AIP Digital Archive
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Topics: |
Physics
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Notes: |
The time-resolved optical reflectivity (at 633-nm wavelength) of ion-implanted silicon is measured during and immediately after CO2 laser irradiation [λ=10.6 μm, pulse duration (FWHM)=70 ns] as a function of the energy density of the laser. For a heavily doped sample and incident energy densities greater than 2.9 J/cm2, the reflectivity of the probe beam is found to rapidly jump to 70%, which is consistent with the reflectivity of liquid silicon. The high-reflectivity phase lasts for up to 1 μs, indicating a relatively deep molten layer as compared to similar annealing experiments with a visible or ultraviolet laser. The transmittance and reflectance (at 10.6-μm wavelength) of ion-implanted silicon are also reported as a function of the energy density of the CO2 laser. For energy densities slightly exceeding a threshold value, the transmittance (reflectance) of the tailing edge of the pulse is found to greatly decrease (increase). The interpretation of the optical measurements is based on a thermal model in which surface melting occurs for incident energy densities exceeding a threshold value.
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Type of Medium: |
Electronic Resource
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URL: |