Semiconductor Device, Method for Manufacturing the Semiconductor Device, and Display Device Including the Semiconductor Device

• US 20160155803A1
• Filed: 11/25/2015
• Published: 06/02/2016
• Est. Priority Date: 11/28/2014
• Status: Abandoned Application

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Koezuka, Junichi, Okazaki, Kenichi, Jintyou, Masami, NAKAZAWA, Yasutaka, Obonai, Toshimitsu, SHIMA, Yukinori, Kurosaki, Daisuke
• Application Number:
  US14/952,459
• Publication Number:
  US 20160155803A1
• Time in Patent Office: 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 27/127 with a particular formation, treatment or patterning of the active layer specially adapted to the circuit arrangement
• 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 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• 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 is inhibited and reliability is improved in a semiconductor device including an oxide semiconductor film. The semiconductor device includes a gate electrode, a gate insulating film over the gate electrode, an oxide semiconductor film over the gate insulating film, and a pair of electrodes over the oxide semiconductor film. The oxide semiconductor film includes a channel region and n-type regions in contact with the pair of electrodes. The channel region has fewer oxygen vacancies than the n-type regions.

Claims

1. A semiconductor device comprising:

a gate electrode;

a gate insulating film over the gate electrode;

an oxide semiconductor film over the gate insulating film; and

a pair of electrodes over the oxide semiconductor film,

wherein the oxide semiconductor film comprises a channel region and n-type regions in contact with the pair of electrodes, and

wherein the channel region has fewer oxygen vacancies than the n-type regions.

2. The semiconductor device according to claim 1, further comprising an oxide insulating film over the oxide semiconductor film and the pair of electrodes.

3. The semiconductor device according to claim 2, wherein oxygen atoms of more than or equal to 8.0×

10¹⁴ atoms/cm² are detected from the oxide insulating film by thermal desorption spectroscopy.

4. The semiconductor device according to claim 1, wherein the channel region has a thinner region than a region of the oxide semiconductor film under the pair of electrodes.

5. The semiconductor device according to claim 1,

wherein the oxide semiconductor film comprises In, Zn, and M, and

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

6. The semiconductor device according to claim 1,

wherein the oxide semiconductor film comprises a crystal part, and

wherein the crystal part has c-axis alignment and comprises a portion whose c-axis is parallel to a normal vector of a surface over which the oxide semiconductor film is fanned.

7. A display device comprising:

the semiconductor device according to claim 1; and

a display element.

8. A display module comprising:

the display device according to claim 7; and

a touch sensor

9. An electronic device comprising:

the semiconductor device according to claim 1, the display device according to claim 7, or the display module according to claim 8; and

an operation key or a battery.

10. A semiconductor device comprising:

a first gate electrode;

a gate insulating film over the first gate electrode;

an oxide semiconductor film over the gate insulating film;

a pair of electrodes over the oxide semiconductor film;

an oxide insulating film over the oxide semiconductor film and the pair of electrodes;

a nitride insulating film over the oxide insulating film; and

a second gate electrode over the nitride insulating film,

wherein the oxide semiconductor film comprises a channel region and n-type regions in contact with the pair of electrodes, and

wherein the channel region has fewer oxygen vacancies than the n-type regions.

11. The semiconductor device according to claim 10, wherein the channel region has a thinner region than a region of the oxide semiconductor film under the pair of electrodes.

12. The semiconductor device according to claim 10,

wherein the oxide semiconductor film comprises In, Zn, and M, and

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

13. The semiconductor device according to claim 10,

wherein the oxide semiconductor film comprises a crystal part, and

wherein the crystal part has c-axis alignment and comprises a portion whose c-axis is parallel to a normal vector of a surface over which the oxide semiconductor film is formed.

14. The semiconductor device according to claim 10, wherein oxygen atoms of more than or equal to 8.0×

10¹⁴ atoms/cm² are detected from the oxide insulating film by thermal desorption spectroscopy.

15. A display device comprising:

the semiconductor device according to claim 10; and

a display element.

16. A display module comprising:

the display device according to claim 15; and

a touch sensor

17. An electronic device comprising:

the semiconductor device according to claim 10, the display device according to claim 15, or the display module according to claim 16; and

an operation key or a battery.

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

forming a gate electrode over a substrate;

forming a gate insulating film over the gate electrode;

forming an oxide semiconductor film over the gate insulating film;

forming a conductive film over the oxide semiconductor film to form a region having oxygen vacancies in the oxide semiconductor film;

processing the conductive film to form a pair of electrodes; and

removing the region of the oxide semiconductor film which is between the pair of electrodes with a chemical solution or a gas.

19. The method for manufacturing a semiconductor device according to claim 18, further comprising the steps of:

forming an oxide insulating film over the oxide semiconductor film and the pair of electrodes; and

adding oxygen to the oxide insulating film.

20. The method for manufacturing a semiconductor device according to claim 18, wherein the conductive film is formed with a sputtering apparatus.

21. The method for manufacturing a semiconductor device according to claim 18, wherein the conductive film is formed with the power density of greater than or equal to 1 W/cm² and less than or equal to 4 W/cm².