An image forming apparatus comprises an exposure unit forming an electrostatic latent image on a photo conductor based on image information, a developing unit developing the electrostatic latent image by toner made of formation material of a circuitry layer, and an electrostatic transferring unit transferring a toner image on the photo conductor onto a substrate. The toner image is transferred so as to cover at least a part of a conductor layer formed on the substrate. At this time, excessive charges caused in the conductor layer accompanying the start of the transfer of the toner image are removed. Alternatively, charges of which polarity is reverse to that of the toner are added to the conductor layer. These allow the circuitry layer to be formed to have a desired pattern favorably and securely on the conductor layer.