A semiconductor element formed over the same substrate as a TFT, includes a semiconductor film having an impurity region; an insulating film formed over the semiconductor film; an electrode divided into a plurality of parts over the insulating film by spacing a distance a in a first direction (channel width direction); an insulator with a width b formed to be in contact with a side wall of the electrodes and an insulator formed in a region between the electrodes divided into a plurality of parts; a silicide layer formed over part of the surface of the impurity region; and characteristics of the TFT are evaluated by measuring resistance of the semiconductor film of the semiconductor element.