This invention concerns with a semiconductor device which is characterized in
that the device is provided with a thin film transistor 40 having a polycrystalline
semiconductor layer 11, the semiconductor layer 11 including a channel
area 22, highly doped drain areas 24, 17 positioned on both sides
of the channel area 22 and LDD areas 18a, 18b positioned
between the channel area 22 and the highly doped drain areas 24, 17 and
lower in dopant density than the highly doped drain areas 24, 17, wherein
any diameter of the crystal 14 at least partly existing in the LDD area
18b is larger than the size of other crystals 15.
