A method for manufacturing a liquid crystal display device includes forming
a gate line and a gate electrode on a substrate, forming a gate insulating
layer on an entire surface of the substrate including the gate line,
forming a semiconductor layer on the gate insulating layer above the gate
electrode, depositing a metal layer on an entire surface of the gate
insulating layer including the semiconductor layer, forming a mask pattern
for patterning a data line and source and drain electrodes on the metal
layer, and forming a data line perpendicular to the gate line, and the
source and drain electrodes by simultaneously removing portions of the
metal layer with the mask pattern and removing a first thickness of the
gate insulating layer.
