Semiconductor device comprising first metal oxide film and second metal oxide film

• US 10,217,776 B2
• Filed: 09/30/2016
• Issued: 02/26/2019
• Est. Priority Date: 08/31/2012
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Katayama, Masahiro, Sato, Ami, Shima, Yukinori
• Primary Examiner(s): Malsawma, Lex
• Assistant Examiner(s): Cross, Xia
• Application Number:
  US15/281,165
• Publication Number:
  US 20170018578A1
• Time in Patent Office: 879 Days
• CPC Class Codes: G02F 1/13306 Circuit arrangements or driving methods for the control of single liquid crystal cells G02F1/132, G02F1/133382 take precedence
• CPC Class Codes: G02F 1/133302 Rigid substrates, e.g. inorganic substrates
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/134336 Matrix
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: H01L 27/0629 in combination with diodes, or resistors, or capacitors
• 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 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• 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 semiconductor device including a capacitor having an increased charge capacity without decreasing an aperture ratio is provided. The semiconductor device includes a transistor including a light-transmitting semiconductor film, a capacitor in which a dielectric film is provided between a pair of electrodes, and a pixel electrode electrically connected to the transistor. In the capacitor, a conductive film formed on the same surface as the light-transmitting semiconductor film in the transistor serves as one electrode, the pixel electrode serves as the other electrode, and a nitride insulating film and a second oxide insulating film which are provided between the light-transmitting semiconductor film and the pixel electrode serve as the a dielectric film.

Claims

1. A semiconductor device comprising:

a first insulating film;

a first metal oxide film portion on and in contact with the first insulating film;

a second metal oxide film portion on and in contact with the first insulating film;

a transistor comprising the first metal oxide film portion as a channel formation region; and

a pixel electrode overlapping the second metal oxide film portion,

wherein a second insulating film is on and in direct contact with the second metal oxide film portion and overlaps the first metal oxide film portion,

wherein a third insulating film is interposed between the first metal oxide film portion and the second insulating film and overlaps the second metal oxide film portion, and

wherein a concentration in hydrogen of the second metal oxide film portion is greater than or equal to 8×

10¹⁹ atoms/cm³.

2. The semiconductor device according to claim 1,

wherein the concentration in hydrogen of the second metal oxide film portion is greater than or equal to 10²⁰ atoms/cm³.

3. The semiconductor device according to claim 1,

wherein the concentration in hydrogen of the second metal oxide film portion is greater than or equal to 5×

10²⁰ atoms/cm³.

4. The semiconductor device according to claim 1,

wherein the second insulating film comprises more nitrogen than oxygen, and

wherein the third insulating film comprises more oxygen than nitrogen.

5. The semiconductor device according to claim 1, further comprising a pixel portion,

wherein the first metal oxide film portion and the second metal oxide film portion are part of a pixel circuit localized in the pixel portion.

6. The semiconductor device according to claim 1,

wherein the first metal oxide film portion and the second metal oxide film portion belong to two physically separate island-shaped metal oxide films.

7. The semiconductor device according to claim 1,

wherein each of the first metal oxide film portion and the second metal oxide film portion contains more indium than gallium and more indium than zinc in atomic percentages.

8. The semiconductor device according to claim 1,

wherein an indium proportion is about equal as an addition of a gallium proportion and a zinc proportion in each of the first metal oxide film portion and the second metal oxide film portion, in atomic percentages.

9. The semiconductor device according to claim 1,

wherein each of the first metal oxide film portion and the second metal oxide film portion is formed from an In—

Ga—

Zn-based metal oxide containing In, Ga, and Zn at an atomic ratio of 3;

1;

2.

10. The semiconductor device according to claim 1,

wherein a concentration in hydrogen of the first metal oxide film portion is more than 1×

10¹⁶ atoms/cm³ and less than 5×

10¹⁹ atoms/cm³.

11. The semiconductor device according to claim 1,

wherein the third insulating film is on and in direct contact with the second metal oxide film portion.

12. A semiconductor device comprising:

a first insulating film;

a first metal oxide film portion on and in contact with the first insulating film;

a second metal oxide film portion on and in contact with the first insulating film;

a transistor comprising the first metal oxide film portion as a channel formation region; and

a pixel electrode overlapping the second metal oxide film portion,

wherein a second insulating film is on and in direct contact with the second metal oxide film portion and overlaps the first metal oxide film portion,

wherein a third insulating film is interposed between the first metal oxide film portion and the second insulating film and overlaps the second metal oxide film portion,

wherein a concentration in hydrogen of the second metal oxide film portion is greater than or equal to 8×

10¹⁹ atoms/cm³, and

wherein a resistivity of the second metal oxide film portion is greater than or equal to 1×

10<sup>−

8</sup> times and less than or equal to 1×

10<sup>−

1</sup> times a resistivity of the first metal oxide film portion.

13. The semiconductor device according to claim 12,

wherein a conductivity of the second metal oxide film portion is greater than or equal to 10 S/cm and less than or equal to 1000 S/cm.

14. The semiconductor device according to claim 12,

wherein a conductivity of the second metal oxide film portion is greater than or equal to 100 S/cm and less than or equal to 1000 S/cm.

15. The semiconductor device according to claim 12,

wherein the second insulating film comprises more nitrogen than oxygen, and

wherein the third insulating film comprises more oxygen than nitrogen.

16. The semiconductor device according to claim 12, further comprising a pixel portion,

wherein the first metal oxide film portion and the second metal oxide film portion are part of a pixel circuit localized in the pixel portion.

17. The semiconductor device according to claim 12,

wherein the first metal oxide film portion and the second metal oxide film portion belong to two physically separate island-shaped metal oxide films.

18. The semiconductor device according to claim 12,

wherein each of the first metal oxide film portion and the second metal oxide film portion contains more indium than gallium and more indium than zinc in atomic percentages.

19. The semiconductor device according to claim 12,

wherein an indium proportion is about equal as an addition of a gallium proportion and a zinc proportion in each of the first metal oxide film portion and the second metal oxide film portion, in atomic percentages.

20. The semiconductor device according to claim 12,

wherein each of the first metal oxide film portion and the second metal oxide film portion is formed from an In—

Ga—

Zn-based metal oxide containing In, Ga, and Zn at an atomic ratio of 3;

1;

2.

21. The semiconductor device according to claim 12,

wherein a concentration in hydrogen of the first metal oxide film portion is more than 1×

10¹⁶ atoms/cm³ and less than 5×

10¹⁹ atoms/cm³.

22. The semiconductor device according to claim 12,

wherein the third insulating film is on and in direct contact with the second metal oxide film portion.