Method for manufacturing data line, method for manufacturing array substrate and display device

A method for manufacturing an array substrate, comprising:

• forming a gate layer on a substrate;
• forming an insulating layer on a side of the gate layer away from the substrate;
• forming a first conductive layer on the insulating layer;
• forming a first photoresist layer on a side of the conductive layer away from the substrate;
• exposing and then developing the first photoresist layer to form a first groove penetrating the first photoresist layer, thus obtaining a patterned first photoresist layer;
• and
• depositing a first functional material electrochemically on the patterned first photoresist layer, then removing the patterned first photoresist layer to obtain the first conductive layer with a patterned first functional material layer, thereby obtaining the array substrate.