TFT substrate and manufacturing method thereof

A manufacturing method of a thin-film transistor (TFT) substrate, comprising the following steps:

• step 1, providing a backing plate, forming a first insulation layer on the backing plate, depositing and patterning a second metal layer on the first insulation layer, and forming a second insulation layer on the second metal layer,
• wherein the second metal layer comprises a plurality of peripheral signal wiring traces;
• step 2, forming, in the second insulation layer at locations corresponding to each of the peripheral signal wiring traces, a plurality of vias that is arranged in an extension direction of each of the peripheral signal wiring traces and extends through the second insulation layer;
• step 3, depositing and patterning a third metal layer on the second insulation layer such that the third metal layer is formed at a location corresponding to each of the peripheral signal wiring traces and is electrically connected, through the plurality of vias, with each of the peripheral signal wiring traces;
• and
• step 4, depositing a third insulation layer on the second insulation layer and the third metal layer to complete the manufacture of the TFT substrate;
• wherein the plurality of peripheral signal wiring traces comprises high level direct-current (DC) signal lines, low level DC signal lines, and clock signal lines of a gate-driver-on-array (GOA) circuit and grounding lines of the TFT substrate.