电子器件应用光固化聚二甲基硅氧烷薄膜上的选择性贵金属沉积调制

Selective metal-vapor deposition on organic surfaces is an interesting phenomenon and is applicable to prepare fine metal patterns for various electronic and photonic devices based on vacuum evaporation without a shadow mask. However, selective metal-vapor deposition with photochromic diarylethenes has not been successful for noble metals such as Au, Ag and Cu, which are generally used in the electronics field. In this paper, we report deposition modulation of noble-metal vapor on a photocurable polydimethylsiloxane (PDMS) film. When Au, Ag or Cu was vacuum-deposited on the UV-curable PDMS, Au and Cu formed a film on the surface even on the uncured film. Ag, however, was desorbed from the uncured film, and a small amount of evaporated Ag atoms was absorbed into the film. This metal species dependence on metal-deposition/desorption tendency was correlated with the intrinsic vapor pressure of metal species; metals with a high vapor pressure tend to desorb. The uncured film with a small amount of Ag deposition was easily removed with a hexane rinse, leaving only Ag on the cured film. Using this principle, various Ag-film patterns were prepared by irradiating upon UV light with a photomask to form a cured pattern and using maskless Ag deposition. Furthermore, we succeeded in fabrication of fine Ag patterns with a width of several micron by UV-laser scanning and maskless Ag-vapor deposition. This method would be applied to the electrode/wiring for various electronic devices.