Semiconductor device

• US 9,246,047 B2
• Filed: 08/06/2013
• Issued: 01/26/2016
• Est. Priority Date: 08/10/2012
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Bachner, Robert
• Assistant Examiner(s): Rahman, Moin
• Application Number:
  US13/959,768
• Publication Number:
  US 20140042432A1
• Time in Patent Office: 903 Days
• Field of Search: 257/13, 257 79-103, 257/918, 257/40, 257642-643, 257/759, 438 22- 47, 438/69, 438/493, 438/503, 438/507, 438/956
• US Class Current: 1/1
• 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 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/0041 characterised by field-effect operation

Abstract

A semiconductor device in which charge capacity of a capacitor is increased without a reduction in aperture ratio is provided. In a transistor including a light-transmitting semiconductor film and a capacitor in which a dielectric film is provided between a pair of electrodes, the pair of electrodes and the dielectric film are formed using a light-transmitting material. A semiconductor film which is formed on the same surface as the semiconductor film of the transistor is used as one of the pair of electrodes. The dielectric film included in the capacitor is formed using a gate insulating film. The other of the pair of electrodes is formed using a light-transmitting semiconductor film or a light-transmitting conductive film.

Claims

1. A semiconductor device comprising:

a transistor comprising;

a gate electrode over and in contact with an insulating surface;

an insulating layer over the gate electrode; and

a semiconductor layer including a channel formation region over and in contact with the insulating layer, the semiconductor layer containing oxygen, indium, zinc and a metal other than indium and zinc; and

a capacitor comprising;

a first conductive layer over and in contact with the insulating surface;

the insulating layer over the first conductive layer; and

a second conductive layer over and in contact with the insulating layer, the second conductive layer containing oxygen, indium, zinc and the metal,

wherein each of the semiconductor layer, the first conductive layer, the insulating layer and the second conductive layer is capable of transmitting light, and

wherein the second conductive layer includes a region having a higher conductivity than the channel formation region of the semiconductor layer.

2. The semiconductor device according to claim 1, wherein the first conductive layer includes an oxide semiconductor.

3. The semiconductor device according to claim 1, wherein the first conductive layer contains one or more elements selected from boron, nitrogen, fluorine, aluminum, phosphorus, arsenic, indium, tin, antimony, and a rare gas element.

4. The semiconductor device according to claim 1,

wherein the second conductive layer is electrically connected to a pixel electrode being electrically connected to one of a source and a drain of the transistor, and

wherein the semiconductor device is configured to set a potential of the first conductive layer higher than a potential of the pixel electrode when being driven.

5. A display device comprising the semiconductor device according to claim 1.

6. An electronic device comprising the semiconductor device according to claim 1.

19. The semiconductor device according to claim 1, wherein the semiconductor layer and the second conductive layer are formed from a same layer.

22. The semiconductor device according to claim 1, comprising a first insulating layer in contact with the second conductive layer, the first insulating layer containing nitrogen.

24. The semiconductor device according to claim 1, comprising:

a first insulating layer over and in contact with the semiconductor layer and the second conductive layer, the first insulating layer containing oxygen; and

a second insulating layer over and in contact with the first insulating layer, the second insulating layer containing nitrogen,

wherein oxygen content in the first insulating layer is higher than that in the stoichiometric composition.

7. A semiconductor device comprising:

a transistor comprising;

a gate electrode;

a first semiconductor layer including a channel formation region, the first semiconductor layer containing oxygen, indium, zinc and a metal other than indium and zinc; and

an insulating layer between the gate electrode and the first semiconductor layer; and

a capacitor comprising;

a first conductive layer;

the insulating layer over the first conductive layer; and

a second conductive layer over the insulating layer, the second conductive layer containing oxygen, indium, zinc and the metal,

wherein each of the first semiconductor layer, the first conductive layer, the insulating layer and the second conductive layer is capable of transmitting light,

wherein the second conductive layer is a semiconductor layer being over and in contact with a same surface as the first semiconductor layer, and

wherein the second conductive layer includes a region having a higher conductivity than the channel formation region of the first semiconductor layer.

8. The semiconductor device according to claim 7, wherein the first conductive layer includes an oxide semiconductor.

9. The semiconductor device according to claim 7, wherein the first conductive layer contains one or more elements selected from boron, nitrogen, fluorine, aluminum, phosphorus, arsenic, indium, tin, antimony, and a rare gas element.

10. The semiconductor device according to claim 7,

wherein the second conductive layer is electrically connected to a pixel electrode being electrically connected to one of a source and a drain of the transistor, and

wherein the semiconductor device is configured to set a potential of the first conductive layer higher than a potential of the pixel electrode when being driven.

11. A display device comprising the semiconductor device according to claim 7.

12. An electronic device comprising the semiconductor device according to claim 7.

20. The semiconductor device according to claim 7, wherein the first semiconductor layer and the second conductive layer are formed from a same layer.

23. The semiconductor device according to claim 7, comprising a first insulating layer in contact with the second conductive layer, the first insulating layer containing nitrogen.

25. The semiconductor device according to claim 7, comprising:

a first insulating layer over and in contact with the first semiconductor layer and the second conductive layer, the first insulating layer containing oxygen; and

a second insulating layer over and in contact with the first insulating layer, the second insulating layer containing nitrogen,

wherein oxygen content in the first insulating layer is higher than that in the stoichiometric composition.

13. A semiconductor device comprising:

a transistor comprising;

a gate electrode;

a first semiconductor layer including a channel formation region, the first semiconductor layer containing oxygen, indium, zinc and a metal other than indium and zinc; and

an insulating layer between the gate electrode and the first semiconductor layer; and

a capacitor comprising;

a first conductive layer;

a dielectric layer over the first conductive layer; and

a second conductive layer over the dielectric layer, the second conductive layer containing oxygen, indium, zinc and the metal,

wherein each of the first semiconductor layer, the first conductive layer, the dielectric layer and the second conductive layer is capable of transmitting light,

wherein the second conductive layer is a semiconductor layer being over and in contact with a same surface as the first semiconductor layer,

wherein the dielectric layer has a stacked-layer structure of a nitride insulating layer and an oxide insulating layer,

wherein the second conductive layer is in contact with the nitride insulating layer, and

wherein the second conductive layer includes a region having a higher conductivity than the channel formation region of the first semiconductor layer.

14. The semiconductor device according to claim 13, wherein the first conductive layer includes an oxide semiconductor.

15. The semiconductor device according to claim 13, wherein the first conductive layer contains one or more elements selected from boron, nitrogen, fluorine, aluminum, phosphorus, arsenic, indium, tin, antimony, and a rare gas element.

16. The semiconductor device according to claim 13,

wherein the second conductive layer is electrically connected to a pixel electrode being electrically connected to one of a source and a drain of the transistor, and

wherein the semiconductor device is configured to set a potential of the first conductive layer higher than a potential of the pixel electrode when being driven.

17. A display device comprising the semiconductor device according to claim 13.

18. An electronic device comprising the semiconductor device according to claim 13.

21. The semiconductor device according to claim 13, wherein the first semiconductor layer and the second conductive layer are formed from a same layer.

26. The semiconductor device according to claim 13, comprising:

a first insulating layer over and in contact with the first semiconductor layer and the second conductive layer, the first insulating layer containing oxygen; and

a second insulating layer over and in contact with the first insulating layer, the second insulating layer containing nitrogen,

wherein oxygen content in the first insulating layer is higher than that in the stoichiometric composition.