Optical studies during pulsed CO/sub 2/ laser irradiation of ion-implanted silicon

Journal Article · Wed May 15 04:00:00 EDT 1985 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.335335· OSTI ID:5825744

James, R B; Narayan, J; Wood, R F; Ottesen, D K; Siegfriedt, K F

The time-resolved optical reflectivity (at 633-nm wavelength) of ion-implanted silicon is measured during and immediately after CO/sub 2/ laser irradiation (lambda = 10.6 ..mu..m, 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/cm/sup 2/, 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 ..mu..s, 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-..mu..m wavelength) of ion-implanted silicon are also reported as a function of the energy density of the CO/sub 2/ 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.

• Research Organization: Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
• OSTI ID: 5825744
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 57:10; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
CARBON DIOXIDE LASERS
COLLISIONS
CRYSTAL DOPING
ELEMENTS
GAS LASERS
HEATING
ION IMPLANTATION
LASER-RADIATION HEATING
LASERS
LIGHT TRANSMISSION
OPTICAL PROPERTIES
PHOTON COLLISIONS
PHYSICAL PROPERTIES
PLASMA HEATING
REFLECTIVITY
SEMIMETALS
SILICON
SURFACE PROPERTIES