Selective Patterning of Conductive Silver on Polyimide Film by Localized Microplasma Reduction and Electroless Deposition

Abstract

A facile method combined directly and selectively microplasma reduction of ion-exchanged Ag+ to Ag(0) nanoparticle precursors and electroless deposition is introduced to produce highly conductive silver patterns on polyimide (Ag/PI) film. Different silver patterns on both 2D and 3D substrates are successfully fabricated. These silver patterns are well defined and uniform over the whole treatment areas. The EDS, XRD and XPS results indicate that the produced silver is well crystallized in the metallic state with high quality. The resistivity of the straight silver pattern with the thickness of ca. 320 nm is down to 3.89 ± 0.4 μΩ cm, which is about 2.4 times of the bulk silver. Additionally, the result of folding test verifies the high adhesion strength and good mechanical flexibility of the fabricated silver film. Finally, the patterned Ag/PI film is demonstrated to be used as highly conductive path to light a LED bulb, and can be also empolyed as flexible electrode to sense and record biopotential signals.