An object of the present invention is to attain proper display free from improper display conditions, such as crosstalk, improper contrast and uneven display. Another object is to obtain a high aperture ratio by reducing a margin for bonding. Light shielding films are used to cover the overlap portion of the source electrode and the semiconductor layer and the overlap portion of the drain electrode and the semiconductor layer of a bottom gate type TFT device, such as a staggered type. This structure can suppress off-current due to light leakage, and can prevent deterioration of display quality.