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 cm²·V^-1·s^-1.