Display apparatus using oxide semiconductor and production method thereof

• US 8,164,256 B2
• Filed: 11/30/2007
• Issued: 04/24/2012
• Est. Priority Date: 12/05/2006
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Sano, Masafumi, Takahashi, Kenji
• Primary Examiner(s): Hines, Anne
• Assistant Examiner(s): Diaz, Jose M
• Application Number:
  US12/515,190
• Publication Number:
  US 20100045179A1
• Time in Patent Office: 1,607 Days
• Field of Search: 313498-512, 257/368
• US Class Current: 313/509
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays

Abstract

A display apparatus includes a light-emitting layer, a pair of electrodes sandwiching the light-emitting layer, a transistor with an active layer for driving the light-emitting layer through the pair of the electrodes, and a matrix wiring portion having a scanning electrode line, a signal electrode line, and a first insulating layer. The active layer has an oxide which contains In and Zn and at least a part of which is amorphous, and further includes a second insulating layer containing hydrogen in an amount of less than 3×10²¹ atoms/cm³ disposed between the active layer and the first insulating layer.

Claims

1. A display apparatus, comprising:

a transistor with an active layer;

a scanning electrode line operationally connected to the transistor;

a signal electrode line operationally connected to the transistor; and

a first insulating layer in contact with at least one of the scanning electrode line and the signal electrode line,

wherein the active layer comprises an oxide which contains In and Zn and at least a part of which is amorphous,

wherein a second insulating layer containing hydrogen in an amount of less than 3×

10²¹ atoms/cm³ is disposed between the active layer and the first insulating layer,

wherein the first insulating layer contains hydrogen, and

wherein the hydrogen content in the second insulating layer is less than the hydrogen content in the first insulating layer.

2. The display apparatus according to claim 1, wherein the transistor has a source electrode and a drain electrode which are in contact with the active layer,

wherein the active layer comprises a first portion and a second portion, with the second portion being in contact with the source electrode and the drain electrode, and

further comprising a third insulating layer in contact with the first portion of the active layer and not in contact with the second portion.

3. The display apparatus according to claim 1, wherein the third insulating layer contains hydrogen in an amount of less than 3×

10²¹ atoms/cm³.

4. The display apparatus according to claim 1, wherein the scanning electrode line, the signal electrode line, the first insulating layer, and the transistor are disposed in series or in parallel, and

wherein the first insulating layer and the active layer are in contact with each other through the second insulating layer.

10. The display apparatus according to claim 1, further comprising:

a pair of electrodes; and

a light-emitting layer between the pair of electrodes,

wherein the transistor is electrically connected to one of the pair of electrodes.

11. The display apparatus according to claim 1, wherein the second insulating layer is a gate insulating layer.

12. The display apparatus according to claim 1, wherein the first insulating layer comprises at least one selected from the group consisting of silicon oxide, a silicon nitride, and silicon nitride oxide, and

wherein the second insulating layer comprises at least one selected from the group consisting of aluminum oxide, yttrium oxide, hafnium oxide, silicon oxide, and silicon nitride.

5. A method of producing a display apparatus, comprising the steps of:

forming a scanning electrode line;

forming a first insulating layer;

forming a signal electrode line;

forming a transistor with an active layer comprising an oxide which contains In and Zn and at least a part of which is amorphous; and

forming a second insulating layer containing hydrogen in an amount of less than 3×

10²¹ atoms/cm³,

wherein the scanning electrode line and the signal electrode line are operationally connected to the transistor,

wherein the first insulating layer is in contact with at least one of the scanning electrode line and the signal electrode line,

wherein the second insulating layer is disposed between the first insulating layer and the active layer,

wherein the first insulating layer contains hydrogen, and

wherein the hydrogen content of the second insulating layer is less than the hydrogen content of the first insulating layer.

6. The method according to claim 5, wherein the formation of the transistor is performed after the formation of the scanning electrode line, the signal electrode line, and the first insulating layer.

8. The method according to claim 5, wherein the transistor has a source electrode and a drain electrode which are in contact with the active layer,

wherein the active layer comprises a first portion and a second portion, with the second portion being in contact with the source electrode and the drain electrode and

further comprising a step of forming a third insulating layer after the formation of the second insulating layer so as to be in contact with the first portion of the active layer and not in contact with the second portion.

9. The method according to claim 8, wherein the third insulating layer contains hydrogen in an amount of less than 3×

10²¹ atoms/cm³.

13. The method according to claim 5, further comprising the step of forming a light-emitting layer and a pair of electrodes sandwiching the light-emitting layer,

wherein the one of the pair of electrodes is electrically connected to the transistor.

14. The method according to claim 5, wherein the forming step of the transistor comprises the forming step of the second insulating layer.

15. The method according to claim 5, wherein the second insulating layer is formed by sputtering.

16. The method according to claim 6, wherein the first insulating layer comprises at least one selected from the group consisting of silicon oxide, silicon nitride, and silicon nitride oxide, and

wherein the second insulating layer comprises at least one selected from the group consisting of aluminum oxide, yttrium oxide, hafnium oxide, silicon oxide, and silicon nitride.

7. A method of producing a display apparatus, comprising the steps of:

forming a matrix wiring portion having a scanning electrode line, a first insulating layer, and a signal electrode line;

forming a transistor with an active layer comprising an oxide which contains In and Zn and at least a part of which is amorphous;

forming a second insulating layer containing hydrogen in an amount of less than 3×

10²¹ atoms/cm³ between the first insulating layer and the active layer; and

forming a light-emitting layer and a pair of electrodes sandwiching the light-emitting layer,

wherein the formation of the transistor is performed after the formation of the matrix wiring portion and either one of the pair of electrodes.

17. A transistor comprising:

an active layer;

a gate electrode; and

a gate insulating layer between the gate electrode and the active layer,

wherein the active layer comprises an oxide which contains In and Zn and at least a part of which is amorphous, and

wherein the gate insulating layer contains hydrogen in an amount of less than 3×

10²¹ atoms/cm³, and

wherein the gate insulating layer is disposed between the active layer and a first insulating layer having a higher hydrogen content than the hydrogen content of the gate insulating layer.

18. The transistor according to claim 17, further comprising a source electrode and a drain electrode which are in contact with the active layer,

wherein the active layer contains a first portion and a second portion, with the second portion being in contact with the source electrode and the drain electrode of the active layer, and the first portion being in contact with a second insulating layer.

19. The transistor according to claim 18, wherein the second insulating layer contains hydrogen in an amount of less than 3×

10²¹ atoms/cm³.

20. The transistor according to claim 17, wherein the first insulating layer and the active layer are in contact with each other through the gate insulating layer.

21. The transistor according to claim 17, wherein the gate insulating layer comprises at least one selected from the group consisting of aluminum oxide, yttrium oxide, hafnium oxide, silicon oxide, and silicon nitride, and

wherein the first insulating layer comprises at least one selected from the group consisting of silicon oxide, silicon nitride, and silicon nitride oxide.