It is an object of the present invention to provide a semiconductor device in which a sophisticated integrated circuit using a polycrystalline semiconductor is formed over a substrate which is weak with heat such as a plastic substrate or a plastic film substrate and a semiconductor device which transmits/receives power or a signal without wires, and a communication system thereof. One feature of the invention is that a semiconductor device, specifically, a processor, in which a sophisticated integrated circuit is fixed to a plastic substrate which is weak with heat by a stripping method such as a stress peel of process method to transmit/receive power or a signal without wires, for example, with an antenna or a light receiving element.