Ming Lun Tseng

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Phase-change material Ge2Sb2Te5 rings with nanometer-scale thickness have been fabricated using the photo-thermal effect of a focused laser beam followed by differential chemical etching. Laser irradiation conditions and etching process parameters are varied to control the geometric characteristics of the rings. We demonstrate the possibility of arranging(More)
We fabricated a three-dimensional five-layered plasmonic resonant cavity by low-cost, efficient and high-throughput femtosecond laser-induced forward transfer (fs-LIFT) technique. The fabricated cavity was characterized by optical measurements, showing two different cavity modes within the measured wavelength region which is in good agreement with numerical(More)
Artificial photosynthesis using semiconductors has been investigated for more than three decades for the purpose of transferring solar energy into chemical fuels. Numerous studies have revealed that the introduction of plasmonic materials into photochemical reaction can substantially enhance the photo response to the solar splitting of water. Until(More)
Ag nanostructures with surface-enhanced Raman scattering (SERS) activities have been fabricated by applying laser-direct writing (LDW) technique on silver oxide (AgOx) thin films. By controlling the laser powers, multi-level Raman imaging of organic molecules adsorbed on the nanostructures has been observed. This phenomenon is further investigated by(More)
photovoltaics, [ 5 ] super-resolution imaging, [ 6 ] and various twodimensional plasmonic lens. [ 7 ] Besides, using nanostructures to project SPP plane waves into the adjacent free space is also an important issue. The interactions of plasmonic nanostructure on SPP wave involve not only the in-plane behavior, but also out-of-plane scattering which is(More)
Femtosecond laser pulses are focused on a thin film of Ge2Sb2Te5 phase-change material, and the transfer of the illuminated material to a nearby substrate is investigated. The size, shape, and phase-state of the fabricated pattern can be effectively controlled by the laser fluence and by the thickness of the Ge2Sb2Te5 film. Results show multi-level(More)
Using a femtosecond laser, we have transformed the laser-direct-writing technique into a highly efficient method that can process AgO(x) thin films into Ag nanostructures at a fast scanning rate of 2000 μm(2)/min. The processed AgO(x) thin films exhibit broad-band enhancement of optical absorption and effectively function as active SERS substrates. Probing(More)
Using femtosecond laser-induced forward transfer techniques we have fabricated gold dots and nanoparticles on glass substrates, as well as nanobumps on gold thin film. The surface morphologies of these structures with different laser fluences and film thicknesses are investigated. We also study the focusing and defocusing properties of the nanofence-an(More)
Amorphous thin films of Ge(2)Sb(2)Te(5), sputter-deposited on a thin-film gold electrode, are investigated for the purpose of understanding the local electrical conductivity of recorded marks under the influence of focused laser beam. Being amorphous, the as-deposited chalcogenide films have negligible electrical conductivity. With the aid of a focused(More)