A method of manufacturing a semiconductor device includes: forming, on one surface of a substrate, source electrodes and drain electrodes, a semiconductor layer provided between the source electrodes and the drain electrodes, and a gate insulator layer provided to cover a surface of the semiconductor layer; forming an insulator layer on a surface of the gate insulator layer, the insulator layer having through portions; and forming electrodes on the gate insulator layer around the bottom of the through portions and on the insulator layer in the vicinity of the through portions by a vapor film formation method simultaneously so as not to come into contact with each other, forming gate electrodes by using the electrodes formed on the gate insulator layer, and forming pixel electrodes electrically connected to the source electrodes or the drain electrodes by using the electrodes foamed on the insulator layer.