a method of forming a low temperature polysilicon thin film transistor includes steps of : providing a substrate ; forming a polysilicon layer on the substrate ; forming a gate oxide layer on the polysilicon layer ; forming a photoresist pattern on the gate oxide layer ; using the photoresist pattern as a mask and etching the gate oxide layer and the polysilicon layer ; removing the photoresist pattern ; forming a gate on the gate oxide layer ; and implanting dopants to form source / drain region by using the gate as a mask .