Fabrication of hydrophobic and corrosion resistant iron thin film by interference exposure using 157nm F2 laser

2017

Jpn. J. Appl. Phys.

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Periodic microswelling structures were photochemically induced on a silicone rubber surface using a 193 nm ArF excimer laser. Microspheres made of silica glass (SiO2) of 2.5 µm diameter were aligned on the silicone rubber surface during laser irradiation; the laser beam was focused on the silicone surface underneath each microsphere. The height and diameter of the formed microswelling structures were found to be controllable by changing the Ar gas flow rate, single-pulse laser fluence, and laser irradiation time. The chemical bonding of the laser-irradiated sample did not change and thus remained to be a silicone, as analyzed by X-ray photoelectron spectroscopy. As a result, microswelling structures of approximately 1.3 µm height and 1.3 µm diameter were successfully obtained. The contact angles of water on the microstructured silicone were measured to be 150° and larger, clearly indicating superhydrophobicity. The mechanism by which the microswellings form their shape was discussed on the basis of the changes in the focal point and spot size during laser irradiation through the SiO2 microsphere.

Section: Introductionmentioning

confidence: 99%

Formation of periodic microswelling structures on silicone rubber surface using ArF excimer laser to realize superhydrophobic property

Nojiri

Pambudi

2017

Jpn. J. Appl. Phys.

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“…For example, when silicone rubber was used as the material to be modified, its surface Micro 2023, 3 603 was modified to pure SiO 2 without carbon contamination, leading to the fabrication of flexible SiO 2 optical waveguides and lightweight, shock-resistant resin windows for electric vehicles [11,12]. In the Fe thin films, we found that a new Fe 3 O 4 layer was formed under the native oxide film (Fe 2 O 3 ) and realized a pure iron thin film that does not rust even in an aqueous NaCl solution [13,14]. Furthermore, in the case of Al thin film, the laser irradiated area can be modified into transparent and crystalline Al 2 O 3 [15].…”

Section: Introductionmentioning

confidence: 95%

F2 Laser-Induced Micro-Reticulated Structural Changes of Amorphous Carbon Thin Films

2023

Micro

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Micro/nanoprocessing of materials using lasers is currently an active research topic. In that research, the choice of the laser to be used is critical, but the F2 laser, which has the shortest wavelength (157 nm) among commercially available lasers, has few research compared to its potential. In this paper, we discovered a new photochemical processing by using an F2 laser to irradiate an amorphous carbon thin film. The short wavelength and high photon energy of the F2 laser can photoexcite the surface of the thin film at high density and generate active oxygen atoms O(1D) by photodecomposition of atmospheric oxygen molecules. As a result, the optical change of the amorphous carbon thin film was induced without thickness reduction, and a micron-sized network-like, reticulated structural change was formed in the thin film surface after one month at the latest. The formed micron-sized reticulated structure was relatively swollen, and a graphitization occurred in the structure, observed by Raman spectroscopy. However, the structure was not observed when the laser irradiated area became smaller. This work has made it possible to form a micron-sized reticulated structure including carbon nanocrystals in an amorphous carbon, which is expected to further expand the applications of carbon materials.

“…When the ArF excimer laser irradiates the surface of silicone rubber, the main chain of Si-O bonds of the silicone rubber is photodissociated into the lower molecules, resulting in photochemical micro-/nano-swelling in the laser-irradiated area [13][14][15][16][17][18][19][20]. Periodically, silica glass microspheres with a diameter of 2.5 µm were aligned on the entire surface of silicone rubber during laser irradiation [21].…”

Section: Introductionmentioning

confidence: 99%

Photochemical Micro-/Nano-Swelling of Silicone Rubber Induced by Long Pulse-Repetition Interval of an ArF Excimer Laser

2021

Electronic Materials

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Long pulse-repetition intervals of 100 to 500 ms of a 193 nm ArF excimer laser successfully increased the height of the photochemical micro-/nano-swelling of silicone rubber, observed with a scanning electron microscope. The effect of the interval was seen despite the heating of the silicone rubber to 80 °C during laser irradiation. The height of the micro-/nano-swelling was saturated when the laser pulse number was 300 or greater, although each of the saturated heights of the micro-/nano-swelling formed by several pulse-repetition intervals was different. Thus, a second ArF excimer laser irradiated the growing micro-/nano-swelling before the saturation; the saturated height of the growing micro-/nano-swelling could be controlled by the pulse-repetition interval of the second ArF excimer laser. To examine the process of micro-/nano-swelling, an early stage of the growth was observed using an atomic force microscope; a dent structure of the micro-/nano-swelling was clearly recognized. In addition, a needle-like structure of the micro-/nano-swelling could be formed when silica glass microspheres were sparsely aligned.