Laser surface modification for selective electroplating of metal: A 2.5 m/s laser direct write process

Abstract

A very fast laser direct write process is described. The process involves laser modification of an insulating seed multilayer to form a conducting surface which can be electroplated. The seed layer is composed of an adhesion layer of TiW, a conducting layer of Au, and a top insulating layer of α-Si. The laser forms a Au-Si mixture without substantially affecting the adhesion layer. Writing speeds of 2.5 m/s have been demonstrated. The laser patterning can be performed in air, and the process works over a broad range of laser power (Pmax/Pmin ∼ 5).