HIGH-SPEED LASER DIRECT WRITING OF TUNGSTEN CONDUCTORS FROM W(CO)6

High-speed laser direct writing of tungsten conductors using tungsten-hexacarbonyl [W(CO)6] is demonstrated. Tungsten lines were constructed on the Si-LSI substrate at a writing speed as high as 300 μm/s with laser-induced low-pressure chemical vapor deposition. This speed is more than two orders of magnitude higher than the previously reported value for this material. Experiments are analyzed within the conventional three-dimensional diffusion theory for the reactant. It has been found that the deposition rate limiting factor is the transport rate for the reactant into the reaction zone. The upper limit of the writing speed is predicted to be of the order of mm/s for the present material.