Patent ID: 8912027

Claim:
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 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 %, wherein a minimum etch selective ratio between the oxide semiconductor, and the data line and the drain electrode satisfies: −0.22+0.002×T, where T denotes a thickness of the data line and the drain electrode, and wherein the data line and the drain electrode comprise copper.