Conventionally, photolithography and anisotropic etching are performed to form a plug between an electrode and a wiring, etc., thereby increasing the number of steps, getting the throughput worse, and producing unnecessary materials. To solve the problems, the present invention provides a method for manufacturing a display device, including the formation steps of a conductive layer or wirings, and a contact plug that can treat a larger substrate. In the case of forming a plug for electrically connecting conductive patterns comprising plural layers, a pillar made of a conductor is formed over a base conductive layer pattern, and then, after an insulating film is formed over the entire surface, the insulating film is etched back to expose the conductor pillar, and a conductive pattern in an upper layer is formed by ink jetting. In this case, when the conductor pillar is processed, a resist to be a mask can be formed in itself by ink jetting.