Photo-resist process

Abstract

Abstract This invention relates to etching metal by a photo-resist process which comprises coating a metal or metal clad, e.g., copper, substrate with a photocurable composition consisting essentially of (1) a polyene containing at least 2 reactive unsaturated carbon to carbon bonds per molecule, (2) a polythiol containing at least two thiol groups per molecule, the total combined functionality of (a) the reactive unsaturated carbon to carbon bonds per molecule in the polyene and (b) the thiol groups per molecule in the polythiol being greater than 4, and (3) 0.0005 to 50 percent by weight of said composition of a photosensitizer, covering said composition with a UV transparent film adherable to the composition in its cured state, exposing said composition through said film and an image bearing transparency or mask to a free radical generator such as electromagnetic radiation having a wave-length of about 2,0007,000 A. or high energy ionizing radiation to selectively cure and insolubilize the exposed portion of the composition and adhere same to the UV transparent film, removing the image bearing transparency and the UV transparent film with substantially all the cured portion of the composition adhering thereto, thus baring the metal beneath the removed cured portion of the composition, exposing the composition remaining on the metal or the metal clad substrate directly to a free radical generator to cure and insolubilize same, removing the exposed metal from the substrate and thereafter removing the cured composition thus leaving defined metal segments on the substrate.

Inventors

• 👤 Christian B Lundsager

Bibliographic Details