Pixel driving circuit, array substrate and display device

A pixel driving circuit, comprising:

• a base substrate;
• a gate layer lead, arranged on a side of the base substrate;
• a first interlayer dielectric layer, arranged on a side of the gate layer lead away from the base substrate, and formed with a first via hole exposing a contact area of the gate layer lead;
• a second interlayer dielectric layer, arranged on a side of the first interlayer dielectric layer away from the base substrate, and formed with a second via hole exposing the first via hole;
• and
• a source drain layer lead, arranged on a side of the second interlayer dielectric layer away from the base substrate, and electrically connected to the gate layer lead through the first via hole and the second via hole;
• wherein the first interlayer dielectric layer and the second interlayer dielectric layer are formed with the same material by different processes in order to have different densities, so that the first via hole and the second via hole are formed to have different slope angles.