It is an object of the present invention to simplify steps needed to process a wiring in forming a multilayer wiring. In addition, when a droplet discharging technique or a nanoimprint technique is used to form a wiring in a contact hole having a comparatively long diameter, the wiring in accordance with the shape of the contact hole is formed, and the wiring portion of the contact hole is likely to have a depression compared with other portions. A penetrating opening is formed by irradiating a light-transmitting insulating film with laser light having high intensity and a pulse high in repetition frequency. A plurality of openings having a minute contact area is provided instead of forming one penetrating opening having a large contact area to have an even thickness of a wiring by reducing a partial depression and also to ensure contact resistance.