TRANSPARENT THIN FILM TRANSISTOR, AND METHOD OF MANUFACTURING THE SAME

• US 20080166475A1
• Filed: 06/14/2007
• Published: 07/10/2008
• Est. Priority Date: 01/08/2007
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Mo, Yeon-Gon, Jeong, Jae-Kyeong, Shin, Hyun-Soo
• Granted Patent: US 8,698,215 B2
• Time in Patent Office: Days
• US Class Current: 427/126.3
• CPC Class Codes: H01L 27/1218 with a particular composition or structure of the substrate
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/127 with a particular formation, treatment or patterning of the active layer specially adapted to the circuit arrangement
• 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

A thin film transistor (TFT) and a method of manufacturing the same such that an ohmic contact can be formed between a semiconductor layer and a source electrode or between the semiconductor layer and a drain electrode, wherein the TFT can be applied to a plastic substrate. The TFT includes: a substrate; an active layer formed of ZnO, InZnO, ZnSnO, and/or ZnInGaO on the substrate and including a channel region, a source region, and a drain region; a gate electrode insulated from the active layer; and source and drain electrodes insulated from the gate electrode and electrically connected to the source region and the drain region, respectively, wherein the source region and the drain region of the active layer include hydrogen.

Claims

1. A thin film transistor (TFT) comprising:

a substrate;

an active layer disposed on the substrate and comprising a channel region, a source region, and a drain region, the active layer including a material selected from the group consisting of ZnO, InZnO, ZnSnO, and ZnInGaO;

a gate electrode insulated from the active layer;

a source electrode insulated from the gate electrode and electrically connected to the source region of the active layer; and

a drain electrode insulated from the gate electrode and electrically connected to the drain region of the active layer,

wherein the source region and the drain region of the active layer comprise hydrogen.

2. The TFT of claim 1, wherein a concentration of hydrogen of the source region and the drain region of the active layer ranges from about 10¹⁸/cm³ to about 10²¹/cm³.

3. The TFT of claim 1, wherein the substrate is a plastic substrate.

4. The TFT of claim 1, wherein the active layer is transparent to light.

5. The TFT of claim 1, further comprising a gate insulating layer disposed on the active layer to be between the gate electrode and the active layer, wherein the gate electrode is disposed on the gate insulating layer.

6. A thin film transistor (TFT) comprising:

a substrate;

a gate electrode disposed on the substrate;

an active layer including a material selected from the group consisting of ZnO, InZnO, ZnSnO, and ZnInGaO and insulated from the gate electrode, the active layer comprising a channel region, a source region, and a drain region;

a source electrode insulated from the gate electrode and electrically connected to the source region of the active layer; and

a drain electrode insulated from the gate electrode and electrically connected to the drain region of the active layer,

wherein the source region and the drain region of the active layer comprise hydrogen.

7. The TFT of claim 6, wherein a concentration of hydrogen of the source region and the drain region of the active layer ranges from about 10¹⁸/cm³ to about 10²¹/cm³.

8. The TFT of claim 6, wherein the substrate is a plastic substrate.

9. The TFT of claim 6, wherein the active layer is transparent to light.

10. The TFT of claim 6, further comprising a gate insulating layer disposed on the gate electrode to be between the gate electrode and the active layer, wherein the active layer is disposed on the gate insulating layer.

11. A method of manufacturing a thin film transistor (TFT), the method comprising:

forming an active layer on a substrate using a material selected from the group consisting of ZnO, InZnO, ZnSnO, and ZnInGaO, the active layer comprising a channel region, a source region, and a drain region;

forming a gate insulating layer to cover the active layer;

forming a gate electrode on the gate insulating layer;

implanting hydrogen ions on the gate insulating layer in order to inject hydrogen into the source region and the drain region of the active layer; and

forming a source electrode and a drain electrode to be electrically connected to the source region and the drain region of the active layer, respectively.

12. The method of claim 11, wherein during the implanting of the hydrogen ions, a hydrogen ion dose ranges from about 1 e¹⁶/cm² to about 1 e¹⁸/cm².

13. The method of claim 11, wherein during the implanting of the hydrogen ions, an injection energy of the hydrogen ions ranges from about 50 keV to about 150 keV.

14. The method of claim 11, further comprising:

heat treating the active layer after the implanting of the hydrogen ions.

15. The method of claim 14, wherein the heat treating of the active layer after the implanting of the hydrogen ions comprises heat treating the active layer at a temperature of about 200°

C.

16. A method of manufacturing a thin film transistor (TFT), the method comprising:

forming a gate electrode on a substrate;

forming a gate insulating layer to cover the gate electrode;

forming an active layer comprising a channel region, a source region, and a drain region on the gate insulating layer using a material selected from the group consisting of ZnO, InZnO, ZnSnO, and ZnInGaO;

forming an interlayer insulating layer to cover the active layer;

implanting hydrogen ions into the interlayer insulating layer to inject hydrogen ions into the source region and the drain region of the active layer; and

forming a source electrode and a drain electrode to be electrically connected to the source region and the drain region of the active layer, respectively.

17. The method of claim 16, wherein during the implanting of the hydrogen ions, a hydrogen ion dose ranges from about 1 e¹⁶/cm² to about 1 e¹⁸/cm².

18. The method of claim 16, wherein during the implanting of the hydrogen ions, an injection energy of the hydrogen ions ranges from about 50 keV to about 150 keV.

19. The method of claim 16, further comprising:

heat treating the active layer after the implanting of the hydrogen ions.

20. The method of claim 19, wherein the heat treating of the active layer after the implanting of the hydrogen ions comprises heat treating the active layer at a temperature of about 200°

C.