Tamara V. Byk

Photochemical Deposition of Ni – Cu Patterns onto Conducting Substrates Employing TiO2 – Pd2 + Layers

The metal photopatterning process employing a thin film of amorphous TiO 2 doped with Pd 2+ and oxalic acid has been developed. The exposure of this photolayer to UV light is believed to yield Pd(I) stabilized in a titanium oxide matrix, while subsequent washing results in formation of Pd nanoparticles through disproportionation. The Pd centers at the exposed areas are capable of inducing electroless nickel plating yielding the adhesive nickel pattern. The electroless copper deposition over patterned Ni allows generation of metal patterns with a resistivity of 4-12 μΩ cm and a resolution of 7 μm on the conducting substrates (indium-tin oxide glass, Si).

Photochemical Patterning of Pd with Amorphous TiO2 Layer and Selective Electroless Deposition of Ni

A novel metal patterning process was developed to reduce the number of chemical processing steps and to obtain 10 μm line width fine patterns. Films of amorphous TiO 2 and water-soluble polyvinyl alcohol were used as photocatalytic layers. UV light was directed through a photomask onto the photocatalytic layers. Pd(II) in an aqueous solution was reduced to Pd(0) by the exposed TiO 2 and deposited on the exposed regions. Selective electroless Ni plating on the Pd patterns provided Ni patterns on the TiO 2 film. Selective growth of carbon nanotubes on the Ni patterns was carried out by plasma-enhanced chemical vapor deposition.

Selective Electroless Deposition Using Photoinduced Oxidation of Sn(II) Compounds on Surface-Modified Polyimide Layers

This paper describes an electroless deposition method for fabricating microscale metal patterns on polyimide surfaces. This method uses the selective deposition of catalytic Pd seeds via the photoinduced oxidation of Sn(II) compounds. The preparation process requires three steps: a first step in which the adsorption of Sn(II) compounds occurs on the surface of the polyimide film through ion exchange reactions, a second step in which the photoinduced oxidation of the Sn(II) compounds with atmospheric oxygen occurs in ultraviolet light (UV) irradiated areas, and a third step comprising the deposition of Pd 2+ ions in nonirradiated areas, which are simultaneously reduced.