Display device comprising dual transistor with LDD regions overlapping the gate electrodes and one of a source electrode and a drain electrode of first transistor is electrically connected to the second gate electrode

A display device comprising:

• a first substrate;
• a first wiring over the first substrate;
• a second wiring over the first substrate;
• a first transistor comprising a first gate electrode, a gate insulating film over the first gate electrode, and a first semiconductor layer comprising a first LDD region over the gate insulating film;
• a second transistor comprising a second gate electrode, the gate insulating film over the second gate electrode, and a second semiconductor layer comprising a second LDD region over the gate insulating film;
• an insulating film over the first transistor and the second transistor;
• a first electrode over the insulating film;
• a light emitting layer over the first electrode;
• a second electrode over the light emitting layer, the second electrode comprising a transparent conductive film;
• a second substrate over the second electrode;
• a first sealing material interposed between the first substrate and the second substrate, the first sealing material being disposed along peripheries of the first and second substrates;
• and
• a second sealing material outside of and along the first sealing material,
• wherein a part of the first LDD region overlaps with the first gate electrode,
• wherein a part of the second LDD region overlaps with the second gate electrode,
• wherein the first gate electrode is electrically connected to the first wiring,
• wherein one of a source electrode and a drain electrode of the second transistor is electrically connected to the second wiring,
• wherein one of a source electrode and a drain electrode of the first transistor is electrically connected to the second gate electrode,
• wherein the light emitting layer does not overlap a channel region of the second semiconductor layer,
• wherein the first sealing material is not in contact with the insulating film,
• wherein the second sealing material is in contact with a side surface of the second substrate,
• wherein the first wiring is parallel to the second wiring.