Display device comprising a second metal layer having a sidewall region with a first thickness and a non-sidewall region with a second thickness larger than the first thickness

A display device, comprising:

• a first substrate;
• a first metal layer disposed on a surface of the first substrate;
• a first insulating layer disposed on the first metal layer, and comprising a first side wall;
• a second insulating layer disposed on the first insulating layer, and comprising a second side wall, a bottom surface, and a top surface, wherein the second side wall is connected between the bottom surface and the top surface, the bottom surface is closer to the first substrate, and the top surface is away from the first substrate;
• a second metal layer covering a part of the top surface of the second insulating layer and comprising a sidewall region and a non-sidewall region, and
• a thin film transistor disposed on the first substrate, wherein the thin film transistor comprises a gate electrode, and the gate electrode is formed by a portion of the first metal layer,
• wherein the sidewall region contacting the second side wall has a first thickness along a direction parallel to the surface of the first substrate, and the non-sidewall region contacting the first metal layer has a second thickness along a direction perpendicular to the surface of the first substrate, and in view of a normal direction of the surface of the first substrate, the sidewall region and the non-sidewall region are not overlapping,
• wherein the first thickness is smaller than the second thickness.