In a semiconductor device, gate signal lines are spaced apart from each other above a crystalline semiconductor film. Therefore a first protective circuit is not electrically connected when contact holes are opened in an interlayer insulating film. The static electricity generated during dry etching for opening the contact holes moves from the gate signal line, damages a gate insulating film, passes the crystalline semiconductor film, and again damages the gate insulating film before it reaches the gate signal line. As the static electricity generated during the dry etching damages the first protective circuit, the energy of the static electricity is reduced until it loses the capacity of damaging a driving circuit TFT. The driving circuit TFT is thus prevented from suffering electrostatic discharge damage.