Abstract
In this research, we demonstrate the laser direct-write technique and report experimental results of depositing copper from the coated copper formate thin film on glass. In order to suppress the surface tension of water against the glass substrate, a surfactant layer was coated between the substrate and copper formate layer. Crystallization of the copper formate has also been eliminated by adding proper amount of glycerol into the water solution. To perform the laser direct-write process, Nd:YAG laser pulses (1064 nm) were focused and scanned on the glass substrates covered by copper formate film. Copper lines were deposited after the copper formate decomposed thermally. With scan speed at 0.25 mm/s and laser pulse energy at 1 mJ, the deposited 10.2- μm copper line showed good adhesion, good uniformity, and low edge roughness. The direct-written linewidth is suitable for TFT-LCD application. However the thickness of the deposited copper line is too thin to provide sufficient conductivity. Therefore, we use the electroplating technique to increase the conductivity and the result seems to be satisfactory.