Raman Vibrational Study of Pulsed Laser Annealing of Implanted GaAs

ABSTRACTThe lattice reconstruction produced by a pulsed laser irradiation in heavily damaged GaAs layers is studied. Spatially resolved Raman measurements are used to characterize the crystalline quality after the annealing cycle produced by a O-switched Ruby laser or by a picosecond pulsed Nd-YAG laser. The continuous evolution in the Raman spectra is usèd to follow the crystal recovery as a function of the irradiation parameters.

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Pulsed Laser Annealing of Aluminum

MRS Proceedings ◽

10.1557/proc-1-567 ◽

1980 ◽

Vol 1 ◽

Cited By ~ 1

Author(s):

W. R. Wampler ◽

D. M. Follstaedt ◽

P. S. Peercy

Keyword(s):

Single Crystal ◽

Laser Irradiation ◽

Reasonable Agreement ◽

Ruby Laser ◽

Laser Annealing ◽

Ion Beam ◽

Pulsed Laser ◽

Nucleation Time ◽

Pulsed Laser Annealing ◽

Beam Analysis

ABSTRACTPulsed ruby laser irradiation of unimplanted single crystal and implanted polycrystalline Al has been studied with ion beam analysis and TEM. The results show that Al is melted to a depth of ∼ 0.9 μm with a 4.2 J/cm2 , 15 nsec pulse, and that vacancies are quenched into Al during resolidification. Diffusion of Zn in liquid Al is observed, and a melt time of ∼ 65 nsec is estimated for a 3.8 J/cm2, 30 nsec pulse. The observations are in reasonable agreement with calculations of sample temperature and melt times. We observe no precipitation of AlSb in liquid Al for Sbimplanted Al, and conclude that the nucleation time satisfies 50 nsec ≲ tnuc ≲ 200 nsec. We find no evidence for amorphous Al after irradiation of single crystal Al with energies ≳ 1.5 J/cm2.

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Pulsed Laser Annealing of Zirconia Capped, Native Oxides Free GaAs Surfaces

MRS Proceedings ◽

10.1557/proc-23-639 ◽

1983 ◽

Vol 23 ◽

Author(s):

D. Pribat ◽

L.M. Mercandalli ◽

M. Croset ◽

J. Siejka

Keyword(s):

Laser Irradiation ◽

Laser Annealing ◽

Defect Density ◽

Pulsed Laser ◽

Native Oxide ◽

Thermally Activated ◽

Native Oxides ◽

Pulsed Laser Annealing ◽

Gaas Substrates ◽

Pulsed Laser Irradiation

ABSTRACTWe have studied the effects of pulsed laser irradiation on silicon implanted, thermally activated , Calcia Stabilized Zirconia (CSZ) capped GaAs substrates. Reference substrates have also been irradiated in air for comparison. CSZ as a solid electrolyte has been used to chemically reduce the GaAs surface native oxides prior to irradiation while maintaining the surface stoechiometry. Our results indicate a spectacular decrease in defect density after laser irradiation of the CSZ capped-native oxide free samples, as compared to the samples irradiated in air.

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Amorphous Phase Trapping as a Result of Pulsed Laser Irradiation of Silicon

MRS Proceedings ◽

10.1557/proc-13-83 ◽

1983 ◽

Vol 13 ◽

Cited By ~ 8

Author(s):

R. F. Wood

Keyword(s):

Phase Transition ◽

Laser Irradiation ◽

Amorphous Phase ◽

Laser Annealing ◽

Pulsed Laser ◽

Rate Model ◽

Kinetic Rate ◽

Pulsed Laser Annealing ◽

Thermodynamic Effect ◽

Pulsed Laser Irradiation

ABSTRACTIt is concluded that large interface undercoolings of ˜ 300 deg are not likely to occur during pulsed laser annealing and that the observed liquid to amorphous phase transition is not a purely thermodynamic effect. It is then shown that the formation of the amorphous phase can be understood on the basis of a kinetic rate model which makes large undercoolings of the interface unnecessary.

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Stress Effects on Raman Measurements of Pulsed Laser Annealed Silicon

MRS Proceedings ◽

10.1557/proc-23-153 ◽

1983 ◽

Vol 23 ◽

Cited By ~ 7

Author(s):

G. E. Jellison ◽

R. F. Wood

Keyword(s):

Raman Scattering ◽

Laser Irradiation ◽

Laser Annealing ◽

Phonon Frequency ◽

Pulsed Laser ◽

Front Surface ◽

Surface Region ◽

Pulsed Laser Annealing ◽

Anti Stokes ◽

Pulsed Laser Irradiation

ABSTRACTIt has recently been shown that the front surface region of the silicon lattice is severely strained during pulsed laser irradiation. This uniaxial strain reduces the symmetry of the front surface region, resulting in additional shifts and splittings of the phonon frequency and changes in the Raman scattering tensor. It is shown that, for the case of pulsed laser irradiation, the phonon frequency is increased, and the 3-fold degenerate optical phonon is split into a singlet and a doublet. The changes in the Raman scattering tensor make it non-symmetric, and generally invalidate the technique used by Compaan et al. to determine the cross section experimentally. The complications introduced by the presence of stress during pulsed laser annealing, coupled with the temperature dependence of the optical and Raman tensors, make a simple interpretation of the Stokes to anti-Stokes ratio in terms of lattice temperature extremely unreliable.

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Pulsed-Laser Annealing of Ion-Implanted GaAs: Theory and Exeriment

MRS Proceedings ◽

10.1557/proc-1-231 ◽

1980 ◽

Vol 1 ◽

Cited By ~ 6

Author(s):

R. F. Wood ◽

Douglas H. Lowndes ◽

W. H. Christie

Keyword(s):

Laser Irradiation ◽

Laser Annealing ◽

Pulsed Laser ◽

Surface Melting ◽

Pulsed Laser Annealing ◽

Dopant Profile ◽

Theory And Experiment ◽

Good Agreement ◽

Pulsed Laser Irradiation ◽

Catastrophic Damage

ABSTRACTIt is shown that, in the pulsed-laser irradiation of crystalline or lightly damaged GaAs, good agreement is obtained between measured and calculated thresholds for melting, for catastrophic damage due to vaporization, and for the duration of surface melting at various energy densities. Good agreement between theory and experiment is also obtained for dopant profile spreading during pulsed-laser annealing.

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Pulsed Laser Annealing of R.F.Sputtered Amorphous Si : H.Films, Doped with Arsenic

MRS Proceedings ◽

10.1557/proc-4-553 ◽

1981 ◽

Vol 4 ◽

Author(s):

E. Fogarassy ◽

R. Stuck ◽

M. Toulemonde ◽

P. Siffert ◽

J.F. Morhange ◽

...

Keyword(s):

Ruby Laser ◽

Laser Annealing ◽

Pulsed Laser ◽

Amorphous Layer ◽

High Concentration ◽

Topographic Analysis ◽

Pulsed Laser Annealing ◽

Residual Hydrogen ◽

Silicon Target ◽

Amorphous Si

Arsenic doped amorphous silicon layers have been deposited on silicon single crystals by R.F.cathodic sputtering of a silicon target in a reactive argon-hydrogen mixture, and annealed with a Q-switched Ruby laser. Topographic analysis of the irradiated layers has shown the formation of a crater, due to an evaporation effect of material which could be related to the presence of a high concentration of Ar in the amorphous layer. RBS and Raman Spectroscopy showed that the remaining layer is not recrystallised probably due to inhibition by the residual hydrogen. However, it was found that arsenic diffuses into the monocrystalline substrate by laser induced diffusion of dopant from the surface solid source, leading to the formation of good quality P-N junctions.

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Melting and Laser Annealing in Semiconductors using 0.485 μm and 0.193 μm Pulsed Lasers

MRS Proceedings ◽

10.1557/proc-2-409 ◽

1980 ◽

Vol 2 ◽

Cited By ~ 1

Author(s):

J. Narayan ◽

J. Fletcher ◽

R. E. Eby

Keyword(s):

Laser Irradiation ◽

Excimer Laser ◽

Laser Annealing ◽

Pulsed Laser ◽

Convincing Evidence ◽

Dye Laser ◽

Pulsed Lasers ◽

Displacement Damage ◽

Melting Phenomenon ◽

Pulsed Laser Irradiation

ABSTRACTAnnealing of displacement damage, the dissolution of boron precipitates, the formation of constitution supercooling cells, and the broadening of dopant profiles have been studied in laser annealed silicon. These samples were irradiated with a dye laser (λ = 0.485 µm, τ = 9 ns, E = 0.7–1.2 J cm−2) and an Excimer laser (λ = 0.193 µm, τ= 9 ns, E = 0.5–0.7 J cm−2) pulses. These results can be consistently interpreted by invoking melting during pulsed laser irradiation. Thus these results provide convincing evidence for the melting phenomenon.

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Impurity Activation in N+ Ion-Implanted 6H-SiC with Pulsed Laser Annealing Method

MRS Proceedings ◽

10.1557/proc-640-h5.31 ◽

2000 ◽

Vol 640 ◽

Cited By ~ 2

Author(s):

O. Eryu ◽

K. Aoyama ◽

K. Abe ◽

K. Nakashima

Keyword(s):

Contact Resistance ◽

Laser Irradiation ◽

Carrier Density ◽

Laser Annealing ◽

Pulsed Laser ◽

Surface Region ◽

Near Surface ◽

Pulsed Laser Annealing ◽

Annealing Method ◽

Ion Implanted

ABSTRACTWe have succeeded in pulsed laser annealing of N+ ion-implanted n-type 6H-SiC for increasing the carrier density near surface in order to decrease contact resistance, which induces little redistribution of implanted impurities after laser irradiation. By repeated laser irradiation at low energy density, the ion–implanted impurities were electrically activated without melting the surface region. SiC substrates with impurity concentration of 2×1018 /cm3 were implanted with 30 keV N+ ions with dose of 4.7×1013/cm2. After pulsed laser annealing, a contact resistance was measured to be 5.7×10−5 Ωcm2 using Al electrode on the N+ -implanted layer.

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Electron Energy Distributions During Pulsed Laser Annealing and Damage of Silicon

MRS Proceedings ◽

10.1557/proc-4-97 ◽

1981 ◽

Vol 4 ◽

Cited By ~ 1

Author(s):

R. T. Williams ◽

M. N. Kabler ◽

J. P. Long ◽

J. C. Rife ◽

T. R. Royt

Keyword(s):

Energy Resolution ◽

Laser Annealing ◽

Pulsed Laser ◽

Energy Distributions ◽

Time Resolved ◽

Pulsed Laser Annealing ◽

Cylindrical Mirror ◽

Molten Phase ◽

532 Nm ◽

Pulsed Laser Irradiation

ABSTRACTSpectra of photoelectrons and thermionic electrons emitted from silicon during pulsed laser irradiation at energy densities encompassing the thresholds for laser annealing and damage are reported. Annealing is accomplished with a 90-nsec pulse of 532-nm light, which may be accompanied by a 266-nm probe pulse. A cylindrical mirror analyzer is used for energy resolution of emitted electrons. Time-resolved reflectivity at 633 nm verifies attainment of the high-reflectivity annealing phase. Spectral widths and total yields imply a modest electron temperature (T < 3000 K) during annealing. The data suggest that the work function of the silicon (111) face may increase about 0.6 eV upon transition to the molten phase.

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