The surface modification of polycarbonate (PC) by 193 nm ArF laser radiation with fluences of 24–... more The surface modification of polycarbonate (PC) by 193 nm ArF laser radiation with fluences of 24–62 mJ/cm 2 and pulse numbers of 1–100 is reported. Noticeable changes including microcone structures on irradiated surfaces have been observed through scanning electron microscope (SEM). It has been shown that the geometrical characteristics (apex angle and base diameter) of the microcones depend on the incident laser fluence. With the increase of the radiation fluence the microcone apexes become sharper, however, their base diameters increase. Поверхность поликарбоната модифицирована излучением ArF-лазера на длине волны 193 нм с плот-ностями потоков 24—62 мДж/см 2 и числом импульсов 1—100. С помощью сканирующего электронного микроскопа на облученных поверхностях наблюдались заметные изменения в виде микроконусных струк-тур. Показано, что геометрические характеристики (угол при вершине и диаметр основания) микроко-нусов зависят от плотности энергии падающего лазерного излучения. При увеличении плотности энергии излучения угол при вершине микроконусов становится острее, однако диаметры их оснований увеличива-ются. Ключевые слова: микроструктура, лазерно-индуцированный микроконус, облучение поликарбоната, ArF-лазер. Introduction. Laser processing of polymers is an area of active research due mainly to the large number of potential applications in material and biomedical science [1]. Among all these, laser ablation has been extensively used as an effective method for micromachining of polymers because of their unique physical and chemical properties as well as the high quality of resulting patterns. Excimer lasers, as powerful UV sources, have attractive applications in micromachining of polymers [2–4]. In the laser ablation of polymers, which allows the controlled removal of thin surface layers, a variety of surface morphologies evolves that, depending on polymer properties and irradiation conditions, includes periodic and nonperiodic microstructures. Periodic structures have been widely observed in metals, ceramics, polymers, and semiconductors [5]. Among the many aspects of laser abla-tion, we are interested here in conical structures induced by excimer laser radiation on polycarbonate surfaces. Polycarbonate is a thermoplastic polymeric material that plays an important role in tissue engineering. This is due to the surface properties of polycarbonate, such as morphology, hydrophoby, surface energy, surface charge, chemical composition, and so on [6]. To date, much effort has been exerted toward understanding the mechanisms responsible for these laser-induced conical formations on some commercially available polymers. In this paper we report the evolution of 193 nm ArF laser-induced conical structures on polycarbonate as a function of laser flu
In this paper we investigate the effects of visible to near infrared (NIR) laser illumination on ... more In this paper we investigate the effects of visible to near infrared (NIR) laser illumination on the optical transmission (OT) and morphological (MC) alterations of thin, curved surfaces of polycarbonate (PC). The second harmonic of Nd:YAG laser (532 nm) and two diode lasers (665 and 980 nm) were used as illuminating sources. The morphological changes of the PC surfaces are determined using atomic force microscopy (AFM), demonstrating the appreciable changes caused by shorter wavelengths (higher energy). When analyzing the OT spectra of PC thin films, a measurable decrease in the OT of the PC samples which were illuminated by 532, 665 and 980 nm, in particular 532 nm, for energy densities greater than 25 J/cm 2 can be seen.
The surface modification of polycarbonate (PC) by 193 nm ArF laser radiation with fluences of 24–... more The surface modification of polycarbonate (PC) by 193 nm ArF laser radiation with fluences of 24–62 mJ/cm 2 and pulse numbers of 1–100 is reported. Noticeable changes including microcone structures on irradiated surfaces have been observed through scanning electron microscope (SEM). It has been shown that the geometrical characteristics (apex angle and base diameter) of the microcones depend on the incident laser fluence. With the increase of the radiation fluence the microcone apexes become sharper, however, their base diameters increase. Поверхность поликарбоната модифицирована излучением ArF-лазера на длине волны 193 нм с плот-ностями потоков 24—62 мДж/см 2 и числом импульсов 1—100. С помощью сканирующего электронного микроскопа на облученных поверхностях наблюдались заметные изменения в виде микроконусных струк-тур. Показано, что геометрические характеристики (угол при вершине и диаметр основания) микроко-нусов зависят от плотности энергии падающего лазерного излучения. При увеличении плотности энергии излучения угол при вершине микроконусов становится острее, однако диаметры их оснований увеличива-ются. Ключевые слова: микроструктура, лазерно-индуцированный микроконус, облучение поликарбоната, ArF-лазер. Introduction. Laser processing of polymers is an area of active research due mainly to the large number of potential applications in material and biomedical science [1]. Among all these, laser ablation has been extensively used as an effective method for micromachining of polymers because of their unique physical and chemical properties as well as the high quality of resulting patterns. Excimer lasers, as powerful UV sources, have attractive applications in micromachining of polymers [2–4]. In the laser ablation of polymers, which allows the controlled removal of thin surface layers, a variety of surface morphologies evolves that, depending on polymer properties and irradiation conditions, includes periodic and nonperiodic microstructures. Periodic structures have been widely observed in metals, ceramics, polymers, and semiconductors [5]. Among the many aspects of laser abla-tion, we are interested here in conical structures induced by excimer laser radiation on polycarbonate surfaces. Polycarbonate is a thermoplastic polymeric material that plays an important role in tissue engineering. This is due to the surface properties of polycarbonate, such as morphology, hydrophoby, surface energy, surface charge, chemical composition, and so on [6]. To date, much effort has been exerted toward understanding the mechanisms responsible for these laser-induced conical formations on some commercially available polymers. In this paper we report the evolution of 193 nm ArF laser-induced conical structures on polycarbonate as a function of laser flu
In this paper we investigate the effects of visible to near infrared (NIR) laser illumination on ... more In this paper we investigate the effects of visible to near infrared (NIR) laser illumination on the optical transmission (OT) and morphological (MC) alterations of thin, curved surfaces of polycarbonate (PC). The second harmonic of Nd:YAG laser (532 nm) and two diode lasers (665 and 980 nm) were used as illuminating sources. The morphological changes of the PC surfaces are determined using atomic force microscopy (AFM), demonstrating the appreciable changes caused by shorter wavelengths (higher energy). When analyzing the OT spectra of PC thin films, a measurable decrease in the OT of the PC samples which were illuminated by 532, 665 and 980 nm, in particular 532 nm, for energy densities greater than 25 J/cm 2 can be seen.
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