Display panel

A display panel comprising:

• a substrate on which a plurality of pixels each having a plurality of sub-pixels are arranged;
• a plurality of driving transistors each of which is arranged for each sub-pixel on an upper side of the substrate;
• a plurality of switch transistors each of which is arranged for each sub-pixel on the upper side of the substrate so as to electrically connect one of a source and drain to one of a source and drain of the driving transistor;
• a plurality of holding transistors each of which is arranged for each sub-pixel on the upper side of the substrate so as to electrically connect one of a source and drain to the other of the source and drain of the driving transistor and the other of the source and drain to a gate of the driving transistor;
• an insulating film which is formed to cover the driving transistors, the switch transistors, and the holding transistors and has a plurality of trenches formed in an upper surface thereof;
• a plurality of feed interconnections each which is buried in the trench, electrically connected to the other of the source and drain of the driving transistor, and formed from a conductive layer different from a conductive layer serving as the gates, sources, and drains of the driving transistor, switch transistor, and holding transistor;
• a plurality of ridges which are formed on an upper side of the insulating film in parallel to each other;
• a plurality of sub-pixel electrodes each of which is arrayed on the upper side of the insulating film along the ridges, provided between the ridges in correspondence with each sub-pixel, and electrically connected to one of the source and drain of the driving transistor;
• a light-emitting layer which is formed on an upper surface of the sub-pixel electrode by wet coating;
• and
• a counter electrode which covers the light-emitting layer.