||Study of Fabrication of Metal Structure through Two-photon Reduction of Metal Ion using Femtosecond Pulse Laser
This thesis consists of seven chapters, and fabrication of a structure using metals ions in polymer matrix through two-photon excitation using by femtosecond laser from Chapter 3 to Chapter 6. Poly(N-vinylpyrrolidone) and negative tone photoresist SU-8 as a matrix and tetrachloride auric (iii) acid , silver nitrate and copper (ii) acetate as a ion source were used. At first, the sample including metal ion was prepared and then the femtosecond laser beam irradiated to the sample to fabricate the structure. After fabrication, the obtained structure was observed with an atomic force microscope (AFM) and a scanning electron microscope (SEM) and analyzed with an energy dispersive X-ray spectrometry (EDX), a micro X-ray diffractometer (?-XRD) and an X-ray photoelectron spectroscope (XPS). In Chapter 3, the fabrication of the structure using silver ion was investigated. After fabrication, the obtained structure was directly observed and analyzed with AFM, EDX and XPS. The XPS results indicate that the structure mainly consists of carbon element derived from PVP and the reduced silver atom interacts with carbonyl group in PVP chain because of low concentration of the silver ion. In Chapter 4, the fabrication of the structure using high concentrated silver ion was investigated. The results of the elemental analysis indicate that structure consists of silver and silver oxide which oxidized by oxygen dissolved in the sample. Therefore, the fabrication from the degassed sample was investigated. The results suggest that the silver structure was successfully demonstrated. In Chapter 5, the fabrication using gold ion was investigated. After fabrication, the obtained structure was analyzed with EDX, ?-XRD and XPS. The results indicate that the structure consists of triangle-shaped gold and small amount of SU-8. In addition, the results also indicate that the gold interacts with oxygen in SU-8. In Chapter 6, the fabrication using copper ion was investigated. The fabricated structure was observed and analyzed with AFM, EDX, ?-XRD and XPS. The results indicate that the structure consists of SU-8, photo-reduced copper and copper acetate. Summarization of this thesis is written in Chapter 7.