Array substrate and fabricating method thereof

A fabricating method of an array substrate, comprising the following steps:

• providing a substrate and forming a first gate on the substrate, covering a first insulating layer on the first gate and the substrate, and stacking an active layer on the first insulating layer;
• forming a second insulating layer material on the first insulating layer and the active layer and sequentially depositing a third insulating layer material and a photoresist layer material on the second insulating layer material;
• patterning the photoresist layer from a side of the substrate away from the first gate by using the first gate as a mask to form a photoresist layer so as to make the photoresist layer coincide with an orthographic projection of the first gate;
• etching the second insulating layer material and the third insulating layer material to form a second insulating layer and a third insulating layer, so as to make the third insulating layer coincide with an orthographic projection of the photoresist layer after patterning, and a distance between an edge of the second insulating layer and the source and the drain is greater than a distance between an edge of the third insulating layer and the source and the drain;
• and
• removing the photoresist layer after patterning, depositing a metal layer on the active layer to form a source, a second gate, and a drain simultaneously, and subsequently depositing other functional layers and pixel electrode to obtain an array substrate.