Microfluidic-method-processed p-type NiOx Thin-film Transistors

It's essential to develop patterning deposition methods to simplify the process of device fabrication and then reduce the production cost.In this work, a new patterning deposition method, i.e. microfluidic method, was demonstrated in details.In this technology, a micro-fluidic channel with a width of 80 μm and a height of 2 μm can be constructed between PDMS modules and substrates, and under capillary force precursor drops will move through the channel to form a patterned liquid film which is then fixed on the substrate via thermal treatments, and finally patterned films are prepared.In addition, the thermal-driven solidification process from NiO x precursor powder to oxide was investigated through thermogravimetric/differential thermal analysis (TG-DTA) measurement.And the evolution of phase structure of the NiO x precursor powder was analyzed with respect to post-annealing temperatures.Finally, thin-film transistors were fabricated applying the patterned NiO x thin films as channels, and the optimized device showed typical p-type transistor features, with a field-effect mobility up to 0.8 cm 2 ·V -1 ·s -1 .