Display device and method of manufacturing the same

A display device comprising:

• a first substrate;
• a gate line disposed on the first substrate and including a gate electrode;
• a gate insulating layer disposed on the gate line;
• a semiconductor layer disposed on the gate insulating layer;
• a data line disposed on the semiconductor layer and including a source electrode;
• a drain electrode disposed on the semiconductor layer and facing the source electrode;
• and
• a passivation layer disposed on the data line and the drain electrode,
• wherein the semiconductor layer comprises an oxide semiconductor including indium, tin, and zinc,
• wherein an atomic percent of the indium in the oxide semiconductor is equal to or larger than about 10 at % and equal to or smaller than about 80 at %, an atomic percent of the zinc in the oxide semiconductor is equal to or larger than about 10 at % and equal to or smaller than about 70 at %, and an atomic percent of the tin in the oxide semiconductor is equal to or larger than about 5 at % and equal to or smaller than about 45 at %, and
• wherein the data line and the drain electrode include a lower layer and an upper layer comprising molybdenum, and an intermediate layer comprising aluminum, the intermediate layer being disposed between the lower layer and the upper layer.

A method of manufacturing a display device, the method comprising:

• forming a gate line on a first substrate, the gate line including a gate electrode;
• forming a gate insulating layer on the gate line;
• forming a semiconductor layer by depositing an oxide semiconductor material including indium, tin, and zinc on the gate insulating layer, and then etching the oxide semiconductor material with a first etchant;
• forming a data line including a source electrode and a drain electrode facing the source electrode, by forming a metal layer on the semiconductor layer and then etching the metal layer with a second etchant, the metal layer including copper;
• and
• forming a passivation layer on the data line and the drain electrode;
• wherein an atomic percent of the indium in the oxide semiconductor material is equal to or larger than about 10 at % and equal to or smaller than about 90 at %, an atomic percent of the zinc in the oxide semiconductor is equal to or larger than about 5 at % and equal to or smaller than about 60 at %, and an atomic percent of the tin in the oxide semiconductor is equal to or larger than about 5 at % and equal to or smaller than about 45 at %;
• and
• wherein a minimum etch selective ratio between the oxide semiconductor material and the metal layer satisfies:
• −0.22+0.002×T,
• where T denotes a thickness of the metal layer.