A method for forming a conductive post include: a) forming a liquid repellent portion having a thickness of 100 nm or less by disposing a liquid repellent material in a conductive post forming region on a conductive layer; b) forming an insulation layer having an opening in a region overlapping with the conductive post forming region by disposing a liquid including an insulation layer forming material on the conductive layer having the liquid repellent portion formed thereon and polymerizing the insulation layer forming material; c) disposing metal particulates in the opening; and d) heating the metal particulates at a fusing temperature of the metal particulates or higher so as to fusion bond the metal particulates to each other in order to form the conductive post, and to fusion bond the metal particulates and the conductive layer in order to couple the conductive post with the conductive layer.