Apparatus and process for the production of fine line metal traces

摘要

A metallic substrate such a copper foil has an etch barrier such polyimide, Saran Wrap TM , or other plastic applied. This barrier is thereafter selectively etched or ablated with a laser, for example by passing the light through a phase reticle or phase mask having at least the image information for the fine metallic lines thereon. The remaining barrier then acts in a second etch process to remove the underlying metallic layer. A wet or dry (such as RIE) etch may be employed. Over conventional photoresist exposure methods, the developer and resist steps are eliminated. The laser can precisely pattern the barrier in a single step with the remainder of the production of the required metallic fine lines relying on a simple wet etch, a process whose control parameters are well understood and consume little time. Alternately, a process for the direct ablation of metallic layers is disclosed.