Semiconductor device including oxide semiconductor

• US 9,640,555 B2
• Filed: 06/08/2015
• Issued: 05/02/2017
• Est. Priority Date: 06/20/2014
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Okazaki, Kenichi, Koezuka, Junichi, Jintyou, Masami, Iguchi, Takahiro
• Primary Examiner(s): Monbleau, Davienne
• Assistant Examiner(s): Cruz, Leslie Pilar
• Application Number:
  US14/733,052
• Publication Number:
  US 20150372022A1
• Time in Patent Office: 694 Days
• 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 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/513 the variation being perpendicular to the channel plane
• 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 29/78609 for preventing leakage current H01L29/78618 takes 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

Abstract

A change in electrical characteristics can be inhibited and reliability can be improved in a semiconductor device including an oxide semiconductor. The semiconductor device including an oxide semiconductor film includes a first insulating film, the oxide semiconductor film over the first insulating film, a second insulating film over the oxide semiconductor film, and a third insulating film over the second insulating film. The second insulating film includes oxygen and silicon, the third insulating film includes nitrogen and silicon, and indium is included in a vicinity of an interface between the second insulating film and the third insulating film.

Claims

1. A semiconductor device comprising:

a first insulating film;

an oxide semiconductor film over the first insulating film;

a second insulating film over the oxide semiconductor film; and

a third insulating film over the second insulating film,

wherein the second insulating film includes oxygen and silicon,

wherein the third insulating film includes nitrogen and silicon,

wherein indium is included in a vicinity of an interface between the second insulating film and the third insulating film, and

wherein a concentration of indium at the interface is higher than a concentration of indium at a center of the second insulating film.

2. The semiconductor device according to claim 1,

wherein the indium is detectable in the vicinity of the interface by secondary ion mass spectrometry.

3. The semiconductor device according to claim 1,

wherein the oxide semiconductor film includes O, In, Zn, and M, and

wherein M is Ti, Ga, Sn, Y, Zr, La, Ce, Nd, or Hf.

4. The semiconductor device according to claim 1,

wherein the oxide semiconductor film includes a crystal part, the crystal part having a c-axis parallel to a normal vector of a surface over which the oxide semiconductor film is formed.

5. A display device comprising:

the semiconductor device according to claim 1; and

a display element.

6. A display module comprising:

the display device according to claim 5; and

a touch sensor.

7. An electronic appliance comprising:

the semiconductor device according to claim 1; and

at least one of an operation key and a battery.

8. The semiconductor device according to claim 1,

wherein a concentration of indium in the vicinity of the interface is greater than or equal to 5×

10¹⁶ atoms/cm³.

9. A semiconductor device comprising:

a gate electrode;

a first insulating film over the gate electrode;

an oxide semiconductor film over the first insulating film;

a source electrode electrically connected to the oxide semiconductor film;

a drain electrode electrically connected to the oxide semiconductor film;

a second insulating film over the oxide semiconductor film, the source electrode, and the drain electrode; and

a third insulating film over the second insulating film,

wherein the second insulating film includes oxygen and silicon,

wherein the third insulating film includes nitrogen and silicon,

wherein indium is included in a vicinity of an interface between the second insulating film and the third insulating film, and

wherein a concentration of indium at the interface is higher than a concentration of indium at a center of the second insulating film.

10. The semiconductor device according to claim 9,

wherein the indium is detectable in the vicinity of the interface by secondary ion mass spectrometry.

11. The semiconductor device according to claim 9,

wherein the oxide semiconductor film includes O, In, Zn, and M, and

wherein M is Ti, Ga, Sn, Y, Zr, La, Ce, Nd, or Hf.

12. The semiconductor device according to claim 9,

wherein the oxide semiconductor film includes a crystal part, the crystal part having a c-axis parallel to a normal vector of a surface over which the oxide semiconductor film is formed.

13. A display device comprising:

the semiconductor device according to claim 9; and

a display element.

14. A display module comprising:

the display device according to claim 13; and

a touch sensor.

15. An electronic appliance comprising:

the semiconductor device according to claim 9; and

at least one of an operation key and a battery.

16. The semiconductor device according to claim 9,

wherein a concentration of indium in the vicinity of the interface is greater than or equal to 5×

10¹⁶ atoms/cm³.

17. A semiconductor device comprising:

a first insulating film;

an oxide semiconductor film over the first insulating film;

a second insulating film over the oxide semiconductor film; and

a third insulating film over the second insulating film,

wherein the second insulating film includes oxygen and silicon,

wherein indium is included in a vicinity of an interface between the second insulating film and the third insulating film, and

wherein a concentration of indium at the interface is higher than a concentration of indium at a center of the second insulating film.

18. The semiconductor device according to claim 17,

wherein the indium is detectable in the vicinity of the interface by secondary ion mass spectrometry.

19. The semiconductor device according to claim 17,

wherein the oxide semiconductor film includes O, In, Zn, and M, and

wherein M is Ti, Ga, Sn, Y, Zr, La, Ce, Nd, or Hf.

20. The semiconductor device according to claim 17,

wherein the oxide semiconductor film includes a crystal part, the crystal part having a c-axis parallel to a normal vector of a surface over which the oxide semiconductor film is formed.

21. A display device comprising:

the semiconductor device according to claim 17; and

a display element.

22. A display module comprising:

the display device according to claim 21; and

a touch sensor.

23. An electronic appliance comprising:

the semiconductor device according to claim 17; and

at least one of an operation key and a battery.

24. The semiconductor device according to claim 17,

wherein a concentration of indium in the vicinity of the interface is greater than or equal to 5×

10¹⁶ atoms/cm³.