A Rice University team has modified its laser-induced graphene technique to make high-resolution, micron-scale patterns of the conductive material for consumer electronics and other applications. Laser-induced graphene (LIG), introduced in 2014 by Rice chemist James Tour, involves burning away everything except carbon from polymers or other materials, leaving the carbon atoms to reconfigure themselves into films of characteristic hexagonal graphene. The process employs a commercial laser that “writes” graphene patterns into surfaces that to date have included wood, paper and even food.
The new version writes fine patterns of graphene into photoresist polymers, light-sensitive materials used in photolithography and photoengraving. Baking the film increases its carbon content, and subsequent lasing solidifies the robust graphene pattern, after which unlased photoresist is washed away.