THIN FILM TRANSISTOR AND METHOD FOR PREPARING THE SAME

• US 20100090215A1
• Filed: 04/25/2008
• Published: 04/15/2010
• Est. Priority Date: 04/25/2007
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Lee, Jung-Hyoung
• Granted Patent: US 8,258,023 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

The present invention relates to a thin film transistor and a method of manufacturing the same. More particularly, the present invention relates to a thin film transistor that includes a zinc oxide material including Si as a channel material of a semiconductor layer, and a method of manufacturing the same.

Claims

1. A method of manufacturing a thin film transistor, the method comprising the steps of:

A) forming a gate electrode on a substrate;

B) forming an insulating layer on the substrate and the gate electrode;

C) forming a semiconductor layer on the insulating layer by using a zinc oxide material that comprises Si as a channel material; and

D) forming a source electrode and a drain electrode so as to be connected to the semiconductor layer.

2. The method of manufacturing a thin film transistor according to claim 1, wherein in the forming of the semiconductor layer of step C), the zinc oxide material comprising Si is a material comprising ZnO, ZnO:

Al, ZnO;

Ga, ZnO;

In, or a complex oxide thereof and Si in an amount of more than 0 to 30 mol % or less.

3. The method of manufacturing a thin film transistor according to claim 1, wherein in the forming of the semiconductor layer of step C), the zinc oxide material comprising Si is ZnO—

In₂O₃—

SiO₂.

4. The method of manufacturing a thin film transistor according to claim 3, wherein content of Si is more than 0 to 30 mole % or less, content of Zn is more than 0 to 66 mole % or less, and content of In is more than 0 to 33 mole % or less in ZnO—

In₂O₃—

SiO₂.

5. The method of manufacturing a thin film transistor according to claim 3, wherein a mole % ratio of Zn:

In;

Si of ZnO—

In₂O₃—

SiO₂ is 1;

1;

1.

6. The method of manufacturing a thin film transistor according to claim 1, wherein in the forming of the semiconductor layer of step C), the channel material is a zinc oxide material comprising Si used alone or a material containing the zinc oxide material comprising Si and a Group 1 or 5 material of the periodic table.

8. The method of manufacturing a thin film transistor according to claim 1, further comprising:

after the forming of the semiconductor layer of step C),

1) performing nitrogen doping treatment on the semiconductor layer by using a plasma nitrification process; and

2) performing oxygen heat treatment to the semiconductor layer that is subjected to the nitrogen doping treatment.

9. The method of manufacturing a thin film transistor according to claim 2, wherein in the forming of the semiconductor layer of step C), the zinc oxide material comprising Si is a material comprising ZnO, ZnO:

Al, ZnO;

Ga, ZnO;

In, or a complex oxide thereof and Si in an amount of more than 0 to 30 mol % or less.

10. The method of manufacturing a thin film transistor according to claim 2, wherein in the forming of the semiconductor layer of step C), the zinc oxide material comprising Si is ZnO—

In₂O₃—

SiO₂.

11. The method of manufacturing a thin film transistor according to claim 10, wherein content of Si is more than 0 to 30 mole % or less, content of Zn is more than 0 to 66 mole % or less, and content of In is more than 0 to 33 mole % or less in ZnO—

In₂O₃—

SiO₂.

12. The method of manufacturing a thin film transistor according to claim 10, wherein a mole % ratio of Zn:

In;

Si of ZnO—

In₂O₃—

SiO₂ is 1;

1;

1.

13. The method of manufacturing a thin film transistor according to claim 2, wherein in the forming of the semiconductor layer of step C), the channel material is a zinc oxide material comprising Si used alone or a material containing the zinc oxide material comprising Si and a Group 1 or 5 material of the periodic table.

14. The method of manufacturing a thin film transistor according to claim 8, wherein the plasma nitrification process of step 1) uses one or more selected from NH₃, N₂O, N₂, NO, and NF₃.

15. The method of manufacturing a thin film transistor according to claim 8, wherein the plasma nitrification process of step 1) is performed at a temperature of 200 to 500°

C. for 60 min or less.

16. The method of manufacturing a thin film transistor according to claim 8, wherein the plasma nitrification process of step 1) is an ICP (Inductively Coupled Plasma) type of plasma nitrification process.

17. The method of manufacturing a thin film transistor according to claim 8, wherein in step 2), a rapid thermal annealing method is performed under an oxygen atmosphere at a temperature of 200 to 500°

C. for 1 hour or less as the oxygen heat treatment.

7. (canceled)

18. (canceled)

19. A thin film transistor comprising a substrate;

a gate electrode;

an insulating layer;

a semiconductor layer;

a source electrode; and

a drain electrode, wherein the semiconductor layer comprises a zinc oxide semiconductor channel material comprising Si.

20. The thin film transistor as set forth in claim 19, wherein the semiconductor layer is a semiconductor layer that is sequentially subjected to a plasma nitrification process and then an oxygen heat treatment process after the semiconductor layer is formed.

21. The thin film transistor as set forth in claim 19, wherein the zinc oxide semiconductor channel material comprising Si is a material that comprises ZnO, ZnO:

Al, ZnO;

Ga, ZnO;

In, or a complex oxide thereof and Si in an amount of more than 0 to 30 mole % or less.

22. The thin film transistor as set forth in claim 19, wherein the semiconductor layer comprises a zinc oxide material comprising si used alone or a channel material that comprises a material containing the zinc oxide material comprising si and a group 1 or 5 material of the periodic table.