ポリビニールピロリドン中の銀ナノ粒子の光化学形成とマスクによる直接的金属光パターニング

Abstract

Silver nanoparticle-poly (N-vinylpyrrolidone) composite films (called nano-Ag/PVP) were prepared by Ag+ doped PVP thin films irradiated ultraviolet light. The Ag particles in the films exhibited typical fcc (face-centered-cubic) structural X-ray diffraction peaks with broadened nanoparticle linewidth characteristics where the size of Ag nanoparticle is estimated to be approx. 25 nm. Coordination bonding formation between PVP carbonyl oxygen and silver atoms on nanoparticle surfaces (>C=O--Ag) was also demonstrated by using an FTIR spectrum measurement. The photo-generation processes of nano-Ag/PVP composite films with different Ag+ doping concentration were investigated by using UV-vis absorption spectroscopy. A photo-reduction growth mechanism of Ag nanoparticles in PVP films is presented, including both initial slow induction periods, to form small Ag particles and subsequent rapid growth stage of Ag particles. Finally, direct metal photo-patterning of PVP thin films was realized using 254nm light irradiation of Ag+ doped PVP thin films covered with a mask. So far, silver patterned arrays with a period of 12.5μm (5μm spacing) can be achieved.