SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SAME

• US 20110284959A1
• Filed: 05/03/2011
• Published: 11/24/2011
• Est. Priority Date: 05/20/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: KIMURA, Kunio, ICHIJO, Mitsuhiro, ENDO, Toshiya
• Granted Patent: US 9,490,368 B2
• Time in Patent Office: Days
• US Class Current: 257/347
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2203/64 Normally black display, i.e. the off state being black
• CPC Class Codes: H01L 21/3003 Hydrogenation or deuterisation, e.g. using atomic hydrogen from a plasma
• 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 27/14616 characterised by the channel of the transistor, e.g. channel having a doping gradient
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/66969 of devices having semiconductor bodies not comprising group 14 or group 13/15 materials comprising selenium or tellurium in uncombined form other than as impurities in semiconductor bodies of other materials, comprising cuprous oxide or cuprous iodide H01L21/02365
• CPC Class Codes: H01L 29/78606 with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device H01L29/78642, H01L29/78645 take precedence
• 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: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs

Abstract

One object is to provide a semiconductor device including an oxide semiconductor, which has stable electric characteristics and high reliability. Another object is to manufacture a highly reliable semiconductor device in a high yield. In a top-gate staggered transistor including an oxide semiconductor film, as a first gate insulating film in contact with the oxide semiconductor film, a silicon oxide film is formed by a plasma CVD method with use of a deposition gas containing silicon fluoride and oxygen; and as a second gate insulating film stacked over the first gate insulating film, a silicon oxide film is formed by a plasma CVD method with use of a deposition gas containing silicon hydride and oxygen.

Claims

1. A semiconductor device comprising:

an insulating film;

a source electrode layer and a drain electrode layer over the insulating film;

an island-shaped oxide semiconductor film over the insulating film, the source electrode layer, and the drain electrode layer;

an island-shaped first gate insulating film over and in contact with the island-shaped oxide semiconductor film;

a second gate insulating film over the insulating film, the source electrode layer, the drain electrode layer, the island-shaped oxide semiconductor film, and the island-shaped first gate insulating film; and

a gate electrode layer over the second gate insulating film,

wherein the island-shaped first gate insulating film includes a silicon oxide film containing fluorine,

wherein the second gate insulating film contains hydrogen, and

wherein a hydrogen concentration of the second gate insulating film is higher than a hydrogen concentration of the island-shaped first gate insulating film.

2. The semiconductor device according to claim 1, wherein a thickness of the island-shaped first gate insulating film is smaller than a thickness of the second gate insulating film.

3. The semiconductor device according to claim 1, wherein a thickness of the island-shaped first gate insulating film is greater than or equal to 1 nm and less than or equal to 10 nm.

4. The semiconductor device according to claim 1,

wherein a hydrogen concentration in the island-shaped first gate insulating film is lower than a fluorine concentration in the island-shaped first gate insulating film,

wherein the fluorine concentration is greater than or equal to 1×

10²⁰ atoms/cm³, and

wherein the hydrogen concentration is less than 1×

10²⁰ atoms/cm³.

5. The semiconductor device according to claim 1,

wherein a hydrogen concentration in the second gate insulating film is higher than a fluorine concentration in the second gate insulating film,

wherein the fluorine concentration is less than 1×

10²⁰ atoms/cm³, and

wherein the hydrogen concentration is greater than or equal to 1×

10²⁰ atoms/cm³.

6. The semiconductor device according to claim 1, wherein the semiconductor device is one selected from the group consisting of a laptop personal computer, a personal digital assistant, an electronic book reader, a mobile phone, a digital video camera, and a television set.

7. A semiconductor device comprising:

an insulating film;

a source electrode layer and a drain electrode layer over the insulating film;

an island-shaped oxide semiconductor film over the insulating film, the source electrode layer, and the drain electrode layer;

an island-shaped first gate insulating film over and in contact with the island-shaped oxide semiconductor film;

a second gate insulating film over the insulating film, the source electrode layer, the drain electrode layer, the island-shaped oxide semiconductor film, and the island-shaped first gate insulating film; and

a gate electrode layer over the second gate insulating film,

wherein the island-shaped first gate insulating film includes a silicon oxide film containing fluorine,

wherein the second gate insulating film contains hydrogen,

wherein a hydrogen concentration of the second gate insulating film is higher than a hydrogen concentration of the island-shaped first gate insulating film, and

wherein the insulating film includes a silicon oxide film containing fluorine.

8. The semiconductor device according to claim 7, wherein a thickness of the island-shaped first gate insulating film is smaller than a thickness of the second gate insulating film.

9. The semiconductor device according to claim 7, wherein a thickness of the island-shaped first gate insulating film is greater than or equal to 1 nm and less than or equal to 10 nm.

10. The semiconductor device according to claim 7,

wherein a hydrogen concentration in the island-shaped first gate insulating film is lower than a fluorine concentration in the island-shaped first gate insulating film,

wherein the fluorine concentration is greater than or equal to 1×

10²⁰ atoms/cm³, and

wherein the hydrogen concentration is less than 1×

10²⁰ atoms/cm³.

11. The semiconductor device according to claim 7,

wherein a hydrogen concentration in the second gate insulating film is higher than a fluorine concentration in the second gate insulating film,

wherein the fluorine concentration is less than 1×

10²⁰ atoms/cm³, and

wherein the hydrogen concentration is greater than or equal to 1×

10²⁰ atoms/cm³.

12. The semiconductor device according to claim 7, wherein the semiconductor device is one selected from the group consisting of a laptop personal computer, a personal digital assistant, an electronic book reader, a mobile phone, a digital video camera, and a television set.

13. A manufacturing method of a semiconductor device, comprising the steps of:

forming an insulating film;

forming a source electrode layer and a drain electrode layer over the insulating film;

forming an oxide semiconductor film covering the insulating film, the source electrode layer, and the drain electrode layer;

forming a first gate insulating film over and in contact with the oxide semiconductor film by a plasma chemical vapor deposition method by using a deposition gas containing silicon fluoride and oxygen;

processing the oxide semiconductor film and the first gate insulating film into an island-shaped oxide semiconductor film and an island-shaped first gate insulating film;

forming a second gate insulating film by a plasma chemical vapor deposition method by using a deposition gas comprising silicon hydride and oxygen over the insulating film, the source electrode layer, the drain electrode layer, the island-shaped oxide semiconductor film, and the island-shaped first gate insulating film; and

forming a gate electrode layer over the second gate insulating film.

14. The manufacturing method of a semiconductor device according to claim 13, wherein the island-shaped first gate insulating film is formed by using a deposition gas containing the silicon fluoride and dinitrogen monoxide by a plasma chemical vapor deposition method.

15. The manufacturing method of a semiconductor device according to claim 13, wherein the second gate insulating film is formed by using a deposition gas containing the silicon hydride and dinitrogen monoxide by a plasma chemical vapor deposition method.

16. The manufacturing method of a semiconductor device according to claim 13, wherein the oxide semiconductor film is formed by a sputtering method.

17. A manufacturing method of a semiconductor device, comprising the steps of:

forming an insulating film by a plasma chemical vapor deposition method with use of a deposition gas containing silicon fluoride and oxygen;

forming a source electrode layer and a drain electrode layer over the insulating film;

forming an oxide semiconductor film covering the insulating film, the source electrode layer, and the drain electrode layer;

forming a first gate insulating film over and in contact with the oxide semiconductor film by a plasma chemical vapor deposition method by using a deposition gas containing silicon fluoride and oxygen;

processing the oxide semiconductor film and the first gate insulating film into an island-shaped oxide semiconductor film and an island-shaped first gate insulating film;

forming a second gate insulating film by a plasma chemical vapor deposition method with use of a deposition gas comprising silicon hydride and oxygen over the insulating film, the source electrode layer, the drain electrode layer, the island-shaped oxide semiconductor film, and the island-shaped first gate insulating film; and

forming a gate electrode layer over the second gate insulating film.

18. The manufacturing method of a semiconductor device according to claim 17, wherein the insulating film is formed by using a deposition gas containing the silicon fluoride and dinitrogen monoxide by a plasma chemical vapor deposition method.

19. The manufacturing method of a semiconductor device according to claim 17, wherein the island-shaped first gate insulating film is formed by using a deposition gas containing the silicon fluoride and dinitrogen monoxide by a plasma chemical vapor deposition method.

20. The manufacturing method of a semiconductor device according to claim 17, wherein the second gate insulating film is formed by using a deposition gas containing the silicon hydride and dinitrogen monoxide by a plasma chemical vapor deposition method.

21. The manufacturing method of a semiconductor device according to claim 17, wherein the oxide semiconductor film is formed by a sputtering method.