Micro patterns of some μm size were fabricated by transferring metal thin films using Laser-Induced Forward Transfer (LIFT) technique. The oxygen composition ratio of deposited patterns fabricated by varying laser irradiation conditions was measured by using XPS. Then we investigated the dependence of the oxygen composition ratio of deposited patterns on the thin film-acceptor substrate distance and laser fluence. LIFT was performed using a single shot of KrF excimer laser (wavelength: 248nm, pulse width: 30ns). Sn thin film, with a few hundreds of nanometer thickness deposited on quartz substrate using electron beam evaporation method, were removed by laser irradiation, and deposited on acceptor substrate (Si wafer) after transfer in air under room temperature. As a result of XPS analysis of deposited patterns, it was revealed that the oxygen composition ratio depended on laser fluence and the distance from a thin film to an acceptor substrate and tended to increase and then fall with increase of laser fluence when the film-acceptor substrate distance was fixed. In order to investigate this tendency, we photographed the shadowgraph of the transferring thin film. From this investigation, it was revealed that higher fluence causes higher velocity. As the velocity becomes higher, the time from the beginning of removal to attachment on the acceptor substrate becomes shorter. So the higher laser fluence is, the lower the oxygen composition ratio is.
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