The present invention proposes a TFT, an array substrate, and a method of forming a TFT. The TFT includes a substrate, a buffer layer, a patterned poly-si layer, an isolation layer, a gate layer, and a source/drain pattern layer. The poly-si layer includes a heavily doped source and a heavily doped drain, and a channel. The gate layer includes a first gate area and a second gate area. The source/drain pattern layer includes a source pattern, a drain pattern and a bridge pattern, with the source pattern electrically connecting the heavily doped source, the drain pattern electrically connecting the heavily doped drain, and one end of the bridge pattern connecting the first gate area and the second gate area. The driving ability of the present inventive TFT is enhanced without affecting the leakage current.