Bottom-gate TFT including gate sidewall spacers formed to relax the local electric field concentration

A display device comprising:

• an insulating substrate;
• a metal layer disposed on the insulating substrate;
• an insulating layer disposed on the metal layer;
• and
• a semiconductor layer disposed on the insulating layer, a surface of the semiconductor layer including a first corner, a second corner, a third corner, and a fourth corner in a cross-sectional perspective, including a first horizontal region extending from the first corner and a second horizontal region extending from the fourth corner, and including a first slope region extending from the first corner to the second corner and a second slope region extending from the third corner to the fourth corner, wherein
• the first slope region and the second slope region are disposed between the first horizontal region and the second horizontal region,
• the semiconductor layer includes a channel region of a drive transistor, the channel region disposed between the first slope region and the second slope region, the drive transistor being configured to supply a drive current to a light emitting element of a pixel,
• the first slope region has a first angle with respect to a surface of the insulating substrate,
• a side surface of the metal layer has a fifth corner, a sixth corner, a seventh corner, and an eighth corner in the cross-sectional perspective, and including a third slope region extending from the fifth corner to the sixth corner and a fourth slope region extending from the seventh corner to the eighth corner,
• the first corner, the second corner, the third corner, and the fourth corner are disposed outside the fifth corner, the sixth corner, the seventh corner and the eighth corner of the side surface of the metal layer in a plan view perspective,
• the third slope region has a second angle with respect to the surface of the insulating substrate,
• the first angle is smaller than the second angle, and
• the second angle is greater than zero degrees and less than ninety degrees.