The invention provides a manufacturing method for TFT backplane, through forming an oxygen-containing a-Si layer on the buffer layer and an oxygen-free a-Si layer on the oxygen-containing a-Si layer so that when using a boron induced SPC to crystallize the a-Si thin film, the contact interface between the a-Si thin film and the buffer layer is the oxygen-containing a-Si layer; because the nucleation is not easy to occur in oxygen-containing a-Si layer during high temperature crystallization, the nucleation only occurs top-down in the boron doped layer on the upper surface of the a-Si thin film for good die quality and thin film uniformity to achieve improve crystalline quality and uniformity. The TFT backplane provided by the invention is made with simple process, wherein the crystalline quality and uniformity of the polysilicon layer is preferable, and can enhance the TFT performance and the driving effect.