Crystallization of Optically Thick Amorphous Silicon Films by Near-IR Femtosecond Laser Processing

2020 ◽  
Vol 312 ◽  
pp. 134-139
Author(s):  
Eugeny Mitsai ◽  
Alexander V. Dostovalov ◽  
Kirill A. Bronnikov ◽  
Aleksandr Vladimirovich Nepomniaschiy ◽  
Aleksey Y. Zhizhchenko ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Annealed Film ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Force Microscopy ◽  
Near Ir ◽  
Atomic Force ◽  
Femtosecond Laser Processing ◽  
Amorphous Si ◽  
Si Films

We demonstrated efficient crystallization of amorphous Si films induced by their direct irradiation with near-IR femtosecond laser pulses coming at sub-MHz repetition rate. Comprehensive analysis of morphology and composition of the laser-annealed film by atomic-force microscopy, Fourier-transform IR, Raman and energy dispersive X-ray spectroscopy as well as numerical modeling of optical spectra confirmed efficient crystallization of amorphous Si and high-quality of the obtained films opening pathway for applications in thin-film solar cells, transistors and displays.

Nanofluidic capillaries produced via femtosecond laser induced delamination of thin thermal oxide films from Si(100) substrates

2005 ◽  
Vol 901 ◽  
Author(s):  
Joel Patrick McDonald ◽  
Vanita R. Mistry ◽  
Katherine E. Ray ◽  
Steven M. Yalisove
Keyword(s):  
Femtosecond Laser ◽  
Oxide Films ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Force Microscopy ◽  
Automated Translation ◽  
Atomic Force ◽  
Integrated Devices ◽  
Thermal Oxide ◽  
Translation Stage

AbstractHighly selective and repeatable delamination of thermal oxide films from Si(100) substrates has been performed using single and multiple femtosecond laser pulses forming bubbles or blisters. By overlapping the bubbles laterally, tubes or capillaries can be formed with a range of volumes suitable for nanofluidics. By scanning the sample through the laser using an automated translation stage, patterns of tubes with arbitrary complexity can be formed, while the scan velocity can easily control the volume of the tubes. The production time for capillaries in this fashion is considerably less than with other lithographic techniques, while the proximity of the tubes to the underlying silicon substrate yields the possibility for integrated devices. The mechanism responsible for the delamination will be discussed and the optimal laser and sample translation conditions will be presented which provide the most uniform tubes. Atomic force microscopy and optical microscopy of capillaries with a range of volumes will be presented.

scholarly journals Crystallization of optically thick amorphous silicon films by near-IR femtosecond laser processing

2020 ◽  
Author(s):  
Kirill Bronnikov ◽  
Alexander Dostovalov ◽  
Artem Cherepakhin ◽  
Eugeny Mitsai ◽  
Alexander Nepomniaschiy ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Amorphous Silicon ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Visible Spectral Range ◽  
Ir Radiation ◽  
Optical Elements ◽  
Near Ir ◽  
Lateral Crystallization ◽  
Si Films

Amorphous silicon (α-Si) film present an inexpensive and promising material for optoelectronic and nanophotonic applications. Its basic optical and optoelectronic properties are known to be improved via phase transition from amorphous to polycrystalline phase. Infrared femtosecond laser radiation can be considered as a promising nondestructive and facile way to drive uniform in-depth and lateral crystallization of α-Si films that are typically opaque in UV-visible spectral range. However, so far only a few studies reported on utilization of near-IR radiation for laser-induced crystallization of α-Si providing no information regarding optical properties of the resultant polycrystalline Si films. The present work demonstrates efficient and gentle single-pass crystallization of α-Si films induced by their direct irradiation with near-IR femtosecond laser pulses coming at sub-MHz repetition rate. Comprehensive analysis of morphology and composition of laser-annealed films by atomic-force microscopy, optical, micro-Raman and energy-dispersive X-ray spectroscopy, as well as numerical modeling of optical spectra, confirmed efficient crystallization of α-Si and high-quality of the obtained films. Moreover, we highlight localized laser-driven crystallization of α-Si as a promising way for optical information encryption, anti-counterfeiting and fabrication of micro-optical elements.

scholarly journals Two-Photon Polymerization of Albumin Hydrogel Nanowires Strengthened with Graphene Oxide

Biomimetics ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 66
Author(s):  
Nikita Nekrasov ◽  
Natalya Yakunina ◽  
Vladimir Nevolin ◽  
Ivan Bobrinetskiy ◽  
Pavel Vasilevsky ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Graphene Oxide ◽  
Femtosecond Laser ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Nanoelectromechanical Systems ◽  
Force Microscopy ◽  
Two Photon ◽  
Direct Laser ◽  
Two Photon Polymerization

Multifunctional biomaterials can pave a way to novel types of micro- and nanoelectromechanical systems providing benefits in mimicking of biological functions in implantable, wearable structures. The production of biocomposites that hold both superior electrical and mechanical properties is still a challenging task. In this study, we aim to fabricate 3D printed hydrogel from a biocomposite of bovine serum albumin with graphene oxide (BSA@GO) using femtosecond laser processing. We have developed the method for functional BSA@GO composite nanostructuring based on both two-photon polymerization of nanofilaments and direct laser writing. The atomic-force microscopy was used to probe local electrical and mechanical properties of hydrogel BSA@GO nanowires. The improved local mechanical properties demonstrate synergistic effect in interaction of femtosecond laser pulses and novel composite structure.

Heating of an Atomic Force Microscope tip by femtosecond laser pulses

2010 ◽  
Vol 99 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Alexander A. Milner ◽  
Kaiyin Zhang ◽  
Valery Garmider ◽  
Yehiam Prior
Keyword(s):  
Femtosecond Laser ◽  
Atomic Force Microscope ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Atomic Force

scholarly journals Large-Scale and Localized Laser Crystallization of Optically Thick Amorphous Silicon Films by Near-IR Femtosecond Pulses

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5296
Author(s):  
Kirill Bronnikov ◽  
Alexander Dostovalov ◽  
Artem Cherepakhin ◽  
Eugeny Mitsai ◽  
Alexander Nepomniaschiy ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Amorphous Silicon ◽  
Large Scale ◽  
High Surface ◽  
Femtosecond Laser Pulses ◽  
Visible Spectral Range ◽  
Ir Radiation ◽  
Near Ir ◽  
Si Films ◽  
Induced Crystallization

Amorphous silicon (α-Si) film present an inexpensive and promising material for optoelectronic and nanophotonic applications. Its basic optical and optoelectronic properties are known to be improved via phase transition from amorphous to polycrystalline phase. Infrared femtosecond laser radiation can be considered to be a promising nondestructive and facile way to drive uniform in-depth and lateral crystallization of α-Si films that are typically opaque in UV-visible spectral range. However, so far only a few studies reported on use of near-IR radiation for laser-induced crystallization of α-Si providing less information regarding optical properties of the resultant polycrystalline Si films demonstrating rather high surface roughness. The present work demonstrates efficient and gentle single-pass crystallization of α-Si films induced by their direct irradiation with near-IR femtosecond laser pulses coming at sub-MHz repetition rate. Comprehensive analysis of morphology and composition of laser-annealed films by atomic-force microscopy, optical, micro-Raman and energy-dispersive X-ray spectroscopy, as well as numerical modeling of optical spectra, confirmed efficient crystallization of α-Si and high-quality of the obtained films. Moreover, we highlight localized laser-induced crystallization of α-Si as a promising way for optical information encryption, anti-counterfeiting and fabrication of micro-optical elements.

Structural changes in GaAs induced by ultrafast (fs) laser pulses

1998 ◽  
Vol 13 (7) ◽  
pp. 1808-1811 ◽  
Author(s):  
L. Nánai ◽  
R. Vajtai ◽  
Cs. Beleznai ◽  
J. Remes ◽  
S. Leppävuori ◽  
...  
Keyword(s):  
Structural Changes ◽  
Microprobe Analysis ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Electron Hole ◽  
Zinc Blend ◽  
Force Microscopy ◽  
Atomic Force ◽  
Electron Hole Plasma ◽  
Fs Laser

Ultrafast changes in the crystal structure of GaAs induced by intense femtosecond laser pulses are detected and investigated. Atomic force microscopy and Raman microprobe analysis of the laser-treated area show centrosymmetric (disordered) features which are different from the original zinc-blend structure of the GaAs lattice. The frozen-in structure shows evidence for a special heat transfer from the laser-induced crater to the boundary, namely the heat has been transferred ballistically by a high-density electron-hole plasma.

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