Direct patterning of ZnO thin film transistor using physical vapor jet printing

We developed a direct patterning system that offers a capable approach to the high-resolution patterning of functional materials using a solvent-free and the mask-free method, called the physical vapor jet printing (PVJP) method. In this approach, nanoparticles (NPs) are vaporized from a target material in such a way as to direct their momentum through a microscopic nozzle exit. The vaporized NPs are then patterned onto the substrate, thereby reducing the deposition cost and time, and simplifying the fabrication process. The electrical characteristics of the ZnO-TFTs varied substantially, depending on the oxygen partial pressure. Direct patterned ZnO-TFTs could be fabricated sequentially using the PVJP method. Line-patterned ZnO thin films were prepared, and the on/off ratio was improved from ∼105 to ∼107 due to the decrease in the leakage current.