A method for manufacturing fan-out lines on an array substrate is disclosed. The fan-out lines comprise an amorphous silicon layer, an ohmic contact layer and a source-drain electrode layer disposed on a gate insulating layer. The manufacturing processes can be conducted by forming a first layer of photoresist on the source-drain electrode layer and performing a half-exposure development process on the first layer of photoresist; etching the amorphous silicon layer, the ohmic contact layer and the source-drain electrode layer by an etching process; removing the first layer of photoresist; forming a second layer of photoresist and performing full-exposure development process on the second layer of photoresist; and etching the amorphous silicon layer by etching process to form the fan-out lines.