共查询到20条相似文献,搜索用时 10 毫秒
1.
A. Borowiec M. MacKenzie G.C. Weatherly H.K. Haugen 《Applied Physics A: Materials Science & Processing》2003,76(2):201-207
The final state of the material resulting from laser irradiation of silicon using 130 fs pulses at 790 nm was studied using
a number of techniques including scanning and transmission electron microscopies, as well as atomic force microscopy. Structural
details and the level of damage to the nearby solid following irradiation were characterized and are discussed in the context
of recent dynamical studies.
Received: 28 September 2001 / Accepted: 3 March 2002 / Published online: 19 July 2002
RID="*"
ID="*"Department of Engineering Physics, McMaster University, Hamilton, Ontario, L8S 4M1, Canada
RID="**"
ID="**"Corresponding author. Fax: +1-905/521-2773, E-mail: borowia@mcmaster.ca
RID="***"
ID="***"Present address: Department of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
RID="****"
ID="****"Department of Materials Science and the CEMD, McMaster University, Hamilton, Ontario, L8S 4M1, Canada
RID="*****"
ID="*****"Departments of Engineering Physics, and Physics and Astronomy, and the CEMD, McMaster University, Hamilton, Ontario,
L8S 4M1, Canada 相似文献
2.
Practical uses of femtosecond laser micro-materials processing 总被引:1,自引:0,他引:1
A. Zoubir L. Shah K. Richardson M. Richardson 《Applied Physics A: Materials Science & Processing》2003,77(2):311-315
We describe several approaches to basic femtosecond machining and materials processing that should lead to practical applications.
Included are results on high-throughput deep hole drilling in glasses in ambient air, and precision high-speed micron-scale
surface modification of composite materials and chalcogenide glasses. Ablation of soda-lime silicate glass and PbO lead-silicate
is studied under three different sets of exposure conditions, for which both the wavelength and pulse duration are varied.
Ablation rates are measured below and above the air ionization threshold. The differences observed are explained in terms
of self-channeling in the ablated hole. Fabrication of practical devices such as waveguides and gratings is demonstrated in
chalcogenide glass.
Received: 11 December 2002 / Accepted: 20 January 2003 / Published online: 28 May 2003
RID="*"
ID="*"Corresponding author. Fax: +1-407/8233-570, E-mail: mrichard@mail.ucf.edu 相似文献
3.
M. Lenzner J. Krüger W. Kautek F. Krausz 《Applied Physics A: Materials Science & Processing》1999,69(4):465-466
The threshold fluences for laser-induced damage of fused silica with single 5-fs pulses from a Ti:sapphire laser system were
determined by extrapolating the ablated volume to zero. These thresholds are about 4 times as high as the values previously
obtained from multi-shot experiments. This result is interpreted in terms of an irreversible modification of the original
material below the single-shot threshold (incubation).
Received: 14 June 1999 / Accepted: 24 June 1999 / Published online: 8 September 1999 相似文献
4.
J. Thogersen A. Borowiec H.K. Haugen F.E. McNeill I.M. Stronach 《Applied Physics A: Materials Science & Processing》2001,73(3):361-363
We characterize the spectral properties of X-rays generated from selected metal and semiconductor targets when 120-fs laser
pulses are focused to intensities of∼1014–3×1015 W/cm2 during laser micromachining in air. High fluxes of multi-keV-energy X-rays could be obtained with 280-μJ pulses at a 1 kHz
repetition rate. The yield and spectral composition of the X-rays are found to depend sensitively on the processing conditions,
and thus the X-ray emission is expected to be a novel indicator of optimal laser machining.
Received: 17 July 2000 / Accepted: 27 October 2000 / Published online: 28 February 2001 相似文献
5.
We report on Nd:CNGG active planar waveguides produced by 6.0 MeV carbon ion implantation at fluence from 1 × 1014 ions/cm2 to 8 × 1014 ions/cm2. The refractive index profiles, which were reconstructed according to the measured dark mode spectroscopy, showed that the refractive indices had negative changes in the surface region, forming typical barrier waveguide. The width of waveguide structure induced by carbon ion implantation is ∼3.8 μm. The typical barrier-shaped distribution may be mainly due to the nuclear energy deposition of the incident ions into the substrate. By performing a modal analysis on the observed TE modes, it was found that the TE0 and TE1 modes can be well-confined inside the waveguide. 相似文献
6.
L.-W. Yin M.-S. Li Z.-G. Gong Z.-Y. Hao 《Applied Physics A: Materials Science & Processing》2003,76(7):1079-1084
A type of synthetic diamond single crystal about 0.4–0.5 mm in dimension prepared under high pressure–high temperature (HPHT)
in the presence of a FeNi molten catalyst was quenched from HPHT and irradiated with 300 keV electrons at room temperature.
Transmission electron microscopy was employed to examine the microstructure of the diamond single crystal before and after
electron irradiation. It was found that there exists a large amount of cellular interfaces in the quenched diamond sample,
which indicates the growth condition of the diamond under HPHT. Hexagonal dislocation loops about several tens of nanometers
in dimension were observed in the high-pressure-synthesized diamond single crystal before electron irradiation, which strongly
suggests that a number of vacancies were quenched-in due to rapid quenching from high temperature at the end of diamond synthesis,
and were aggregated in the synthetic diamond to form vacancy disks on the (111) plane, the collapse of such vacancy disks
forming vacancy-type dislocation loops. After electron irradiation, it was found that defect clusters present as interstitial-character
dislocation loops were formed in the electron-irradiated region of the diamond. The interstitial dislocation loops grow with
increase of the irradiation time. The present study, in comparison to previous work on ion implantation on diamond, indicates
that electron irradiation does not induce a phase transformation but produces interstitial dislocation loops due to the migration
of interstitial atoms and vacancies. The result of the study directly indicates that interstitials and vacancies in diamond
are mobile at room temperature under electron irradiation. Nitrogen, as the most important kind of impurity contained in the
HPHT as-grown diamond, probably acts as nucleation of the interstitial loops.
Received: 16 November 2001 / Accepted: 12 June 2002 / Published online: 17 December 2002
RID="*"
ID="*"Corresponding author. E-mail: yinlw@sdu.edu.cn 相似文献
7.
Here we report on experimental studies of femtosecond laser induced surface metal alloying. We demonstrate that layers of different metals can be mixed in a certain range of laser pulse energies. Numeric simulations demonstrate that the sub-surface melting and mixing is advantaged through the difference in the electron-phonon coupling constants of the metals in the multi-layer system. Dependence of the depth of the mixed layer on the number of laser pulses per unit area is studied. Numeric simulations illustrate physical picture of the laser alloying process. 相似文献
8.
M. Lenzner J. Krüger W. Kautek F. Krausz 《Applied Physics A: Materials Science & Processing》1999,68(3):369-371
Received: 4 January 1999 / Accepted: 5 January 1999 相似文献
9.
Modification of the fused silica glass network associated with waveguide fabrication using femtosecond laser pulses 总被引:1,自引:0,他引:1
J.W. Chan T.R. Huser S.H. Risbud D.M. Krol 《Applied Physics A: Materials Science & Processing》2003,76(3):367-372
Atomic-scale structural changes have been observed in the glass network of fused silica after modification by tightly focused
800-nm, 130-fs laser pulses at fluences between 5 and 200 J cm-2. Raman spectroscopy of the modified glass shows an increase in the 490 and 605-cm-1 peaks, indicating an increase in the number of 4- and 3-membered ring structures in the silica network. These results provide
evidence that densification of the glass occurs after exposure to fs pulses. Fluorescence spectroscopy of the modified glass
shows a broad fluorescence band at 630 nm, indicating the formation of non-bridging oxygen hole centers (NBOHC) by fs pulses.
Waveguides that support the fundamental mode at 633 nm have been fabricated inside fused silica by scanning the glass along
the fs laser beam axis. The index changes are estimated to be approximately 0.07×10-3.
Received: 17 December 2001 / Accepted: 9 July 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +1-925/423-2463, E-mail: dmkrol@ucdavis.edu 相似文献
10.
Vertically and laterally waveguide-coupled cylindrical microresonators in Si3N4 on SiO2 technology 总被引:1,自引:0,他引:1
D.J.W. Klunder E. Krioukov F.S. Tan T. van der Veen H.F. Bulthuis G. Sengo C. Otto H.J.W.M. Hoekstra A. Driessen 《Applied physics. B, Lasers and optics》2001,73(5-6):603-608
High-finesse laterally and vertically waveguide-coupled cylindrical microresonators have been designed and realized in Si3N4 on SiO2 technology using conventional optical lithography. Based on the experimental results and detailed simulations, a comparison
between the lateral and vertical coupling schemes is made.
Received: 16 May 2001 / Revised version: 13 August 2001 / Published online: 2 November 2001 相似文献
11.
Microexplosions in tellurite glasses 总被引:2,自引:0,他引:2
S.K. Sundaram C.B. Schaffer E. Mazur 《Applied Physics A: Materials Science & Processing》2003,76(3):379-384
Femtosecond laser pulses were used to produce localized damage in the bulk and near the surface of baseline, Al2O3-doped and La2O3-doped sodium tellurite glasses. Single or multiple laser pulses were non-linearly absorbed in the focal volume by the glass,
leading to permanent changes in the material in the focal volume. These changes were caused by an explosive expansion of the
ionized material in the focal volume into the surrounding material, i.e. a microexplosion. The writing of simple structures
(periodic array of voxels, as well as lines) was demonstrated. The regions of microexplosion and writing were subsequently
characterized using scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS) and atomic force microscopy (AFM).
Fingerprints of microexplosions (concentric lines within the region and a concentric ring outside the region), due to the
shock wave generated during microexplosions, were evident. In the case of the baseline glass, no chemistry change was observed
within the region of the microexplosion. However, Al2O3-doped and La2O3-doped glasses showed depletion of the dopant from the edge to the center of the region of the microexplosions, indicating
a chemistry gradient within the regions. Interrogation of the bulk- and laser-treated regions using micro-Raman spectroscopy
revealed no structural change due to the microexplosions and writing within these glasses.
Received: 27 December 2001 / Accepted: 9 July 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. +1-509/376-3108, E-mail: sk.sundaram@pnl.gov 相似文献
12.
13.
D. Hernández-Maldonado M. Herrera P. Alonso-González L. González P.L. Galindo 《Applied Surface Science》2010,256(18):5659-5661
The compositional distribution of InAs quantum dots grown by molecular beam epitaxy on GaAs capped InAs quantum dots has been studied in this work. Upper quantum dots are nucleated preferentially on top of the quantum dots underneath, which have been nucleated by droplet epitaxy. The growth process of these nanostructures, which are usually called as quantum dots molecules, has been explained. In order to understand this growth process, the analysis of the strain has been carried out from a 3D model of the nanostructure built from transmission electron microscopy images sensitive to the composition. 相似文献
14.
We report on room temperature MeV Au ion induced modifications at the Co/Si interfaces. Nanometers size thin film of Co and Si were grown by ultra high vacuum (UHV) electron beam evaporation technique on Si(1 1 1) surface and were irradiated by 1.5 MeV Au2+ ions at a fluence of 5 × 1014 ions cm−2. High-resolution transmission electron microscopy (HRTEM) along with energy filter imaging technique has been employed to study the formation of Co-Si alloy at the interface. Formation of such surface alloy has been discussed in the light of ion-matter interaction in nanometer scale regime. 相似文献
15.
Received: 21 November 1997/Accepted: 1 April 1998 相似文献
16.
M. Lassithiotaki A. Athanassiou D. Anglos S. Georgiou C. Fotakis 《Applied Physics A: Materials Science & Processing》1999,69(3):363-367
0 ∝t1/2. The best results are expected for a circular top-hat beam shape.
Received: 15 January 1999 / Accepted: 18 January 1999 相似文献
17.
Titanium was laser nitrided by means of free-electron laser irradiation in pure nitrogen atmosphere. The variation of pulse frequency and macropulse duration of the free electron laser resulted in δ-TiNx coatings with different thickness and different micro- and macroscopic morphologies. The coatings revealed, characteristic values for hardness, roughness and crystallographic texture, which originate from the growth mechanism, the solid-liquid interface energy and the strain. Further investigations showed that the dendritic growth is beginning at the surface and that the alignment of dendrites is normal to the surface. A correlation of the texture with the time structure of the laser pulses was found. Numerical simulations were performed and compared with the experimental results. The simulations can explain the experimental results. 相似文献
18.
J. Hübner S. Guldberg-Kjaer M. Dyngaard Y. Shen C.L. Thomsen S. Balslev C. Jensen D. Zauner T. Feuchter 《Applied physics. B, Lasers and optics》2001,73(5-6):435-438
New results in erbium-doped planar waveguide amplifiers and lasers are presented. The waveguides are produced in silica-on-silicon
technology using plasma-enhanced chemical vapor deposition. Waveguide propagation losses outside the erbium absorption band
are improved to values below 0.05 dB/cm for a core–cladding index step of around 1.4%. Amplifier arrays show a net gain of
more than 12 dB over the entire C-band.
Received: 13 June 2001 / Published online: 23 October 2001 相似文献
19.
20.
D. Bäuerle R. Denk J.D. Pedarnig K. Piglmayer J. Heitz G. Schrems 《Applied Physics A: Materials Science & Processing》2003,77(2):203-207
Laser-induced material processing is reviewed with special emphasis on recent achievements mainly obtained by the Linz group.
Among those are investigations using optical fiber tips for nanoscale photophysical etching, laser-induced surface patterning
using self-assembled microspheres, the pulsed-laser deposition of thin films of high-temperature superconductors and the modification
and cleaning of surfaces.
Received: 7 February 2003 / Accepted: 6 March 2003 / Published online: 28 May 2003
RID="*"
ID="*"Corresponding author. Fax: +43-732/2468-9242, E-mail: dieter.baeuerle@jku.at 相似文献