Semiconductor device and fabrication method thereof

A semiconductor device including a pixel matrix circuit comprising:

• a plurality of gate wirings;
• a plurality of source wirings;
• a plurality of bottom gate type thin film transistors arranged to corresponding pixels;
• a plurality of storage capacitances connected to pixel electrodes;
• and
• a crystalline semiconductor film of each of the thin film transistors, said crystalline semiconductor film including a source region, a drain region, and at least one channel forming region,
• wherein each of the source region and the drain region includes toward a gate insulating film,
• at least a first conductive layer,
• at least a second conductive layer having a higher resistance than the first conductive layer, and
• a first semiconductor layer having a same conductive type as the channel forming region,
• wherein a concentration profile of an impurity to give a conductivity to the first and the second conductive layers is varied continuously from the first conductive layer to the second conductive layer, and
• wherein a first electrode of each of the storage capacitances is formed by a conductive film common to the gate wirings while a second electrode thereof is formed by a conductive film common to the source wirings.

A semiconductor device including a pixel matrix circuit comprising:

• a plurality of gate wirings;
• a plurality of source wirings;
• a plurality of bottom gate type thin film transistors arranged to corresponding pixels;
• a plurality of storage capacitances connected to pixel electrodes;
• and
• a crystalline semiconductor film of each of the thin film transistors, said crystalline semiconductor film including a source region, a drain region, and at least one channel forming region
• wherein each of the source region and the drain region includes toward a gate insulating film,
• at least a first conductive layer,
• at least a second conductive layer having a higher resistance than the first conductive layer, and
• at least a first semiconductor layer having a same conductive type as the channel forming region;
• wherein a concentration profile of an impurity to give a conductivity to the first and the second conductive layers is varied continuously from the first conductive layer to the second conductive layer,
• wherein a first electrode of each of the storage capacitances is formed by a conductive film common to the gate wirings, and
• wherein each of the pixel electrodes includes a region in contact with a dielectric body of each of the storage capacitances.