Semiconductor device and method for manufacturing semiconductor device

• US 9,472,682 B2
• Filed: 06/24/2013
• Issued: 10/18/2016
• Est. Priority Date: 06/29/2012
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Okazaki, Kenichi, Koezuka, Junichi, Sasaki, Toshinari
• Primary Examiner(s): Ahmed, Selim
• Assistant Examiner(s): RAHMAN, MOIN M
• Application Number:
  US13/924,757
• Publication Number:
  US 20140001468A1
• Time in Patent Office: 1,212 Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/441 Deposition of conductive or insulating materials for electrodes
• 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 29/78621 with LDD structure or an extension or an offset region or characterised by the doping profile
• 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 29/78693 the semiconducting oxide being amorphous

Abstract

In a top-gate transistor in which an oxide semiconductor film, a gate insulating film, a gate electrode layer, and a silicon nitride film are stacked in this order and the oxide semiconductor film includes a channel formation region, nitrogen is added to regions of part of the oxide semiconductor film and the regions become low-resistance regions by forming a silicon nitride film over and in contact with the oxide semiconductor film. A source and drain electrode layers are in contact with the low-resistance regions. A region of the oxide semiconductor film, which does not contact the silicon nitride film (that is, a region overlapping with the gate insulating film and the gate electrode layer) becomes the channel formation region.

Claims

1. A semiconductor device comprising:

an oxide semiconductor film;

a gate insulating film over the oxide semiconductor film;

a gate electrode layer over the gate insulating film;

a silicon nitride film over the oxide semiconductor film, the gate insulating film, and the gate electrode layer, the silicon nitride film comprising a first opening; and

a first electrode layer over the silicon nitride film, the first electrode layer being in contact with the oxide semiconductor film through the first opening,

wherein in the silicon nitride film, a peak of the number of released hydrogen molecules does not appear at a temperature lower than or equal to 500°

C. in thermal desorption spectroscopy.

2. The semiconductor device according to claim 1, wherein the oxide semiconductor film comprises a crystal having a c-axis which is substantially perpendicular to a surface on which the oxide semiconductor film is formed.

3. The semiconductor device according to claim 1, wherein the oxide semiconductor film comprises phosphorus or boron in a region which is in contact with the first electrode layer.

4. The semiconductor device according to claim 1, further comprising a second electrode layer over the silicon nitride film,

wherein the silicon nitride film further comprises a second opening, and

wherein the second electrode layer is in contact with the oxide semiconductor film through the second opening.

5. A semiconductor device comprising:

an oxide semiconductor film;

a gate insulating film over the oxide semiconductor film;

a gate electrode layer over the gate insulating film;

a silicon nitride film over the oxide semiconductor film, the gate insulating film, and the gate electrode layer, the silicon nitride film comprising a first opening; and

a first electrode layer over the silicon nitride film, the first electrode layer being in contact with the oxide semiconductor film through the first opening,

wherein in the silicon nitride film, the number of released hydrogen molecules is lower than or equal to 1.5×

10²⁰/cm³ at a temperature lower than or equal to 550°

C. in thermal desorption spectroscopy.

6. The semiconductor device according to claim 5, wherein the oxide semiconductor film comprises a crystal having a c-axis which is substantially perpendicular to a surface on which the oxide semiconductor film is formed.

7. The semiconductor device according to claim 5, wherein the oxide semiconductor film comprises phosphorus or boron in a region which is in contact with the first electrode layer.

8. The semiconductor device according to claim 5, further comprising a second electrode layer over the silicon nitride film,

wherein the silicon nitride film further comprises a second opening, and

wherein the second electrode layer is in contact with the oxide semiconductor film through the second opening.

9. A semiconductor device comprising:

an oxide semiconductor film;

a gate insulating film over the oxide semiconductor film;

a gate electrode layer over the gate insulating film;

a silicon nitride film over the oxide semiconductor film, the gate insulating film, and the gate electrode layer, the silicon nitride film comprising a first opening; and

a first electrode layer over the silicon nitride film, the first electrode layer being in contact with the oxide semiconductor film through the first opening,

wherein in the silicon nitride film, the number of released hydrogen molecules is higher than or equal to 1.0×

10²⁰/cm^'"'"'at a temperature higher than or equal to 500°

C. in thermal desorption spectroscopy.

10. The semiconductor device according to claim 9, wherein the oxide semiconductor film comprises a crystal having a c-axis which is substantially perpendicular to a surface on which the oxide semiconductor film is formed.

11. The semiconductor device according to claim 9, wherein the oxide semiconductor film comprises phosphorus or boron in a region which is in contact with the first electrode layer.

12. The semiconductor device according to claim 9, further comprising a second electrode layer over the silicon nitride film,

wherein the silicon nitride film further comprises a second opening, and

wherein the second electrode layer is in contact with the oxide semiconductor film through the second opening.