Method for manufacturing semiconductor device

• US 9,768,314 B2
• Filed: 01/14/2014
• Issued: 09/19/2017
• Est. Priority Date: 01/21/2013
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Koezuka, Junichi, Shima, Yukinori, Hiraishi, Suzunosuke, Okazaki, Kenichi
• Primary Examiner(s): CHOUDHRY, MOHAMMAD M
• Application Number:
  US14/154,799
• Publication Number:
  US 20140206133A1
• Time in Patent Office: 1,344 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 29/42384 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 29/66969 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 29/78618 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 29/78633 with a light shield
• 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: H01L 29/8618 Diodes with bulk potential barrier, e.g. Camel diodes, Planar Doped Barrier diodes, Graded bandgap diodes

Abstract

To reduce defects in an oxide semiconductor film in a semiconductor device. To improve electrical characteristics of and reliability in the semiconductor device including an oxide semiconductor film. A method for manufacturing a semiconductor device includes the steps of forming a gate electrode and a gate insulating film over a substrate, forming an oxide semiconductor film over the gate insulating film, forming a pair of electrodes over the oxide semiconductor film, forming a first oxide insulating film over the oxide semiconductor film and the pair of electrodes by a plasma CVD method in which a film formation temperature is 280° C. or higher and 400° C. or lower, forming a second oxide insulating film over the first oxide insulating film, and performing heat treatment at a temperature of 150° C. to 400° C. inclusive, preferably 300° C. to 400° C. inclusive, further preferably 320° C. to 370° C. inclusive.

Claims

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

forming a first gate electrode over a substrate;

forming a gate insulating film over the first gate electrode;

forming an oxide semiconductor film over the gate insulating film;

forming a pair of electrodes electrically connected to the oxide semiconductor film without performing heat treatment after the oxide semiconductor film is formed;

forming a first oxide insulating film over the oxide semiconductor film by a plasma CVD,

wherein a film formation temperature of the first oxide insulating film is higher than or equal to 280°

C. and lower than or equal to 400°

C.;

forming a second oxide insulating film over the first oxide insulating film; and

performing heat treatment at a temperature higher than or equal to 150°

C. and lower than or equal to 400°

C.,

wherein the heat treatment is performed after forming the pair of the electrodes.

2. The method for manufacturing a semiconductor device according to claim 1,

wherein a treatment chamber is evacuated and a pressure in the treatment chamber is set to be greater than or equal to 100 Pa and less than or equal to 250 Pa by introducing a source gas into the treatment chamber, and

wherein the first oxide insulating film is formed in the treatment chamber by supplying a high-frequency power to an electrode provided in the treatment chamber.

3. The method for manufacturing a semiconductor device according to claim 1,

wherein a treatment chamber is evacuated and a pressure in the treatment chamber is set to be greater than or equal to 100 Pa and less than or equal to 250 Pa by introducing a source gas into the treatment chamber,

wherein the second oxide insulating film is formed in the treatment chamber by supplying a high-frequency power higher than or equal to 0.17 W/cm² and lower than or equal to 0.5 W/cm² to an electrode provided in the treatment chamber, and

wherein a temperature of the substrate placed in the treatment chamber is a temperature higher than or equal to 180°

C. and lower than or equal to 280°

C.

4. The method for manufacturing a semiconductor device according to claim 1,

wherein, as the first oxide insulating film and the second oxide insulating film, a silicon oxide film or a silicon oxynitride film is formed using a deposition gas containing silicon and an oxidizing gas as a source gas.

5. The method for manufacturing a semiconductor device according to claim 1,

wherein, as the first oxide insulating film and the second oxide insulating film, a silicon oxynitride film is formed using silane and dinitrogen monoxide as a source gas.

6. The method for manufacturing a semiconductor device according to claim 1,

wherein the oxide semiconductor film comprises at least one of In and Ga.

7. The method for manufacturing a semiconductor device according to claim 1 further comprising:

forming a nitride insulating film over the second oxide insulating film.

8. The method for manufacturing a semiconductor device according to claim 7 further comprising:

forming a second gate electrode over the nitride insulating film.

9. 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 an oxide film over the oxide semiconductor film;

forming a pair of electrodes electrically connected to the oxide semiconductor film over the oxide film, without performing heat treatment after the oxide film is formed;

forming a first oxide insulating film over the oxide film and the pair of electrodes by a plasma CVD,

wherein a film formation temperature of the first oxide insulating film is higher than or equal to 280°

C. and lower than or equal to 400°

C.;

forming a second oxide insulating film over the first oxide insulating film; and

performing heat treatment at a temperature higher than or equal to 150°

C. and lower than or equal to 400°

C.,

wherein the heat treatment is performed after forming the pair of the electrodes.

10. The method for manufacturing a semiconductor device according to claim 9,

wherein a treatment chamber is evacuated and a pressure in the treatment chamber is set to be greater than or equal to 100 Pa and less than or equal to 250 Pa by introducing a source gas into the treatment chamber, and

wherein the first oxide insulating film is formed in the treatment chamber by supplying a high-frequency power to an electrode provided in the treatment chamber.

11. The method for manufacturing a semiconductor device according to claim 9,

wherein a treatment chamber is evacuated and a pressure in the treatment chamber is set to be greater than or equal to 100 Pa and less than or equal to 250 Pa by introducing a source gas into the treatment chamber,

wherein the second oxide insulating film is formed in the treatment chamber by supplying a high-frequency power higher than or equal to 0.17 W/cm² and lower than or equal to 0.5 W/cm² to an electrode provided in the treatment chamber, and

wherein a temperature of the substrate placed in the treatment chamber is a temperature higher than or equal to 180°

C. and lower than or equal to 280°

C.

12. The method for manufacturing a semiconductor device according to claim 9,

wherein, as the first oxide insulating film and the second oxide insulating film, a silicon oxide film or a silicon oxynitride film is formed using a deposition gas containing silicon and an oxidizing gas as a source gas.

13. The method for manufacturing a semiconductor device according to claim 9,

wherein, as the first oxide insulating film and the second oxide insulating film, a silicon oxynitride film is formed using silane and dinitrogen monoxide as a source gas.

14. The method for manufacturing a semiconductor device according to claim 9,

wherein the oxide semiconductor film comprises at least one of In and Ga.

15. The method for manufacturing a semiconductor device according to claim 9,

wherein the oxide film comprises at least one of elements included in the oxide semiconductor film.

16. The method for manufacturing a semiconductor device according to claim 9,

wherein a conduction band bottom of the oxide film is closer to a vacuum level than a conduction band bottom of the oxide semiconductor film is.

17. The method for manufacturing a semiconductor device according to claim 9 further comprising:

forming a nitride insulating film over the second oxide insulating film.

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

forming a first gate electrode over a substrate;

forming a gate insulating film over the first gate electrode;

forming an oxide semiconductor film over the gate insulating film;

forming a pair of electrodes electrically connected to the oxide semiconductor film after the oxide semiconductor film is formed;

forming a first oxide insulating film over the oxide semiconductor film by a plasma CVD, wherein a film formation temperature of the first oxide insulating film is higher than or equal to 280°

C. and lower than or equal to 400°

C.;

forming a second oxide insulating film over the first oxide insulating film; and

performing heat treatment at a temperature higher than or equal to 150°

C. and lower than or equal to 400°

C.,

wherein no heat treatment is performed during a period between completion of the oxide semiconductor film forming step and completion of the pair of electrodes forming step.