Direct patterning in ZnO film formation by surface discharge technique

Surface discharge that induces nonequilibrium two-dimensional plasma was employed to deposit a ZnO film on a poly(ethylene terephthalate) (PET) substrate. The discharge energy was easily tuned by controlling the grid pattern on the electrode as well as the input AC bias. After irradiating a plasma to the precursor precoated on a substrate for 3 min, a hexagonal ZnO single phase was obtained. The crystallization was restricted within the selective area adjacent to the plasma to leave a clear step after washing the substrate in water. The technique was further developed into direct patterning in film formation.