It is an object of the present invention to provide a semiconductor device in which data can be written except when manufacturing the semiconductor device and that counterfeits can be prevented. Moreover, it is another object of the invention to provide an inexpensive semiconductor device including a memory having a simple structure. The semiconductor device includes a field effect transistor formed over a single crystal semiconductor substrate, a first conductive layer formed over the field effect transistor, an organic compound layer formed over the first conductive layer, and a second conductive layer formed over the organic compound layer, and a memory element includes the first conductive layer, the organic compound, and the second conductive layer. According to the above structure, a semiconductor device which can conduct non-contact transmission/reception of data can be provided by possessing an antenna.