Thin film transistor panel having an etch stopper on semiconductor
View Patent ↗A thin film transistor panel includes an insulating substrate, a gate insulating layer disposed on the insulating substrate, an oxide semiconductor layer disposed on the gate insulating layer, an etch stopper disposed on the oxide semiconductor layer, and a source electrode and a drain electrode disposed on the etch stopper.
1. A panel comprising a thin film transistor, the panel comprising:
a substrate;
a first electrode on the substrate;
a first insulating layer on the first electrode;
an oxide semiconductor pattern on the first insulating layer, the oxide semiconductor pattern comprising a channel region;
an etch stopper on the oxide semiconductor pattern; and
a conductive layer on the substrate, the conductive layer comprising a signal line, a second electrode, and a third electrode,
wherein the second electrode and the third electrode are disposed on the etch stopper and directly on the oxide semiconductor pattern,
wherein except for the channel region of the oxide semiconductor pattern, sidewalls of the oxide semiconductor pattern substantially coincide with sidewalls of the signal line, the second electrode, and the third electrode, and
wherein a work function of the second electrode and the third electrode is lower than a work function of the oxide semiconductor pattern.
2. The panel of claim 1 , wherein at least a portion of a sidewall of the channel region of the oxide semiconductor pattern substantially coincides with at least a portion of a sidewall of the etch stopper.
3. The panel of claim 1 , wherein at least one of the second electrode and the third electrode is disposed directly on an upper surface of the oxide semiconductor pattern without being disposed directly on a sidewall surface of the oxide semiconductor pattern.
4. The panel of claim 3 , wherein the at least one of the second electrode and the third electrode is further disposed directly on a sidewall and an upper surface of the etch stopper.
5. The panel of claim 4 , further comprising:
a second insulating layer on the second electrode and the third electrode and comprising a contact hole exposing the second electrode;
a fourth electrode on the second insulating layer and connected to the second electrode via the contact hole in the second insulating layer.
6. The panel of claim 5 , wherein the second insulating layer comprises a passivation layer.
7. The panel of claim 5 , wherein the second insulating layer comprises a color filter.
8. The panel of claim 5 , wherein:
the oxide semiconductor pattern comprises one or more compounds represented by the formulas A x B x O x and A x B x C x O x ;
A is In, Zn, Ga, Hf, or Cd;
B is Zn, Ga, Sn, or In;
C is Sn, Zn, Cd, Ga, In, or Hf;
O is atomic oxygen;
each x is independently a non-zero integer; and
A, B, and C are different from one another.
9. The panel of claim 8 , wherein the oxide semiconductor pattern comprises one or more of InZnO, InGaO, InSnO, ZnSnO, GaSnO, GaZnO, GaZnSnO, GaInZnO, or HfInZnO.
10. The panel of claim 6 , wherein sidewalls of the oxide semiconductor pattern contact the passivation layer.
11. The panel of claim 1 , wherein the second electrode and the third electrode are each non-oxidized electrodes.
12. The panel of claim 1 , wherein the second electrode and the third electrode are disposed directly on the etch stopper and directly on the oxide semiconductor pattern only.