An electro-optical device includes a semiconductor layer, a gate electrode, and a first insulating film, and a second insulating under the semiconductor layer. The first insulating film overlaps a junction region, but not a channel region, of the semiconductor layer. The gate electrode includes a first extended portion that continuously covers an upper and side face and of the first insulating film at the junction region. The gate electrode includes a second extended portion that overlaps and fills a groove in the second insulating that extends along at least the junction region.