Manufacturing method of TFT substrate and TFT substrate

A manufacturing method of thin film transistor (TFT) substrate, which comprises:

• Step 1:
• providing a base substrate, and forming a data line and a source connected to the data line on the base substrate;
• Step 2:
• forming an active layer, the active layer being at least partially above the source;
• Step 3:
• forming a gate insulating layer on top of the active layer, the source, the data line and the base substrate such that a portion of the gate insulating layer is directly formed on the top of the active layer to completely cover and directly contact entirety of the top of the active layer, and patternizing the gate insulating layer to form a first via corresponding to the active layer;
• Step 4:
• forming a first gate, a second gate and a drain, the first gate and the second gate being on the gate insulating layer and corresponding respectively to two lateral sides of the active layer, the drain being at least partially inside the first via and connected to the active layer through the first via;
• Step 5:
• forming a passivation layer on the drain, the first gate, the second gate and the gate insulating layer, patternizing the passivation layer to form a second via corresponding to the drain;
• and
• Step 6:
• forming a pixel electrode, the pixel electrode being at least partially inside the second via and connected to the drain through the second via,
• wherein the drain is formed after the formation of the gate insulating layer and is filled in the first via of the gate insulating layer such that the connection between drain and the active layer is formed after the formation of the gate insulating layer;
• and
• wherein the second via is located above and corresponding, in position, to the first via such that the second via is communication with the first via and a part of the pixel electrode that is located in the second via is in direct, electrical contact with a part of the drain that is located in the first via and an orthographic projection that is cast by the part of the pixel electrode located in the second via on the base substrate completely covers orthographic projections that are respectively cast by the part of drain located in the first via and the active layer on the base substrate.