SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF

• US 20100163868A1
• Filed: 12/23/2009
• Published: 07/01/2010
• Est. Priority Date: 12/26/2008
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: YAMAZAKI, Shunpei, KOYAMA, Jun, SAKATA, Junichiro
• Granted Patent: US 8,222,092 B2
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: H01L 21/02554 Oxides
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• 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 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 29/24 including, apart from doping materials or other impurities, only semiconductor materials not provided for in groups H01L29/16, H01L29/18, H01L29/20, H01L29/22 including organic materials H10K99/00
• 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 29/7869 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 semiconductor device which includes a thin film transistor having an oxide semiconductor layer and excellent electrical characteristics is provided. Further, a method for manufacturing a semiconductor device in which plural kinds of thin film transistors of different structures are formed over one substrate to form plural kinds of circuits and in which the number of steps is not greatly increased is provided. After a metal thin film is formed over an insulating surface, an oxide semiconductor layer is formed thereover. Then, oxidation treatment such as heat treatment is performed to oxidize the metal thin film partly or entirely. Further, structures of thin film transistors are different between a circuit in which emphasis is placed on the speed of operation, such as a logic circuit, and a matrix circuit.

Claims

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

forming a gate electrode over an insulating surface;

forming an insulating layer over the gate electrode;

forming a metal thin film over the insulating layer;

forming an oxide semiconductor layer over the metal thin film; and

performing oxidation treatment on at least a part of the metal thin film after forming the oxide semiconductor layer.

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

wherein the oxidation treatment is heat treatment which is performed in any one of an atmosphere containing oxygen, air, and a nitrogen atmosphere.

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

wherein the oxide semiconductor layer contains at least one of indium, gallium, and zinc.

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

wherein the metal thin film contains at least one of indium, zinc, tin, molybdenum, and tungsten.

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

wherein at least one of elements which are contained in the oxide semiconductor layer is the same as an element contained in the metal thin film.

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

wherein the metal thin film is formed by any one of a sputtering method, a vacuum vapor deposition method, and a coating method.

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

wherein a thickness of the oxide semiconductor layer is 30 nm to 150 nm, inclusive.

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

wherein a thickness of the metal thin film is smaller than a thickness of the oxide semiconductor layer.

9. A semiconductor device comprising:

a matrix circuit and a driver circuit which drives the matrix circuit over an insulating surface,

wherein the driver circuit comprises a first thin film transistor including a stack of a first oxide semiconductor layer and a second oxide semiconductor layer, the stack overlapping with a first gate electrode with a first gate insulating film interposed therebetween,

wherein the matrix circuit includes a second thin film transistor, the second thin film transistor including a third oxide semiconductor layer overlapping with a second gate electrode with a second gate insulating film interposed therebetween,

wherein the first oxide semiconductor layer comprises a first material,

wherein the second oxide semiconductor layer comprises a second material being different from the first material, and

wherein the third oxide semiconductor layer comprises the second material.

10. The semiconductor device according to claim 9,

wherein electrical resistivity of the first oxide semiconductor layer is lower than electrical resistivity of the second oxide semiconductor layer.

11. The semiconductor device according to claim 9,

wherein the first gate insulating film is over the first gate electrode,

wherein the first oxide semiconductor layer is over the first gate insulating film, and

wherein the second oxide semiconductor layer is over the first oxide semiconductor layer.

12. The semiconductor device according to claim 9,

wherein the second gate insulating film is over the second gate electrode, and

wherein the third oxide semiconductor layer is over the second gate insulating film.

13. The semiconductor device according to claim 9,

wherein the second oxide semiconductor layer contains at least one of indium, gallium, and zinc.

14. The semiconductor device according to claim 9,

wherein a thickness of the second oxide semiconductor layer and a thickness of the third oxide semiconductor layer are each 30 nm to 150 nm, inclusive.

15. The semiconductor device according to claim 9,

wherein a thickness of the first oxide semiconductor layer is smaller than a thickness of the second oxide semiconductor layer.

16. A method for manufacturing a semiconductor device comprising a matrix circuit and a driver circuit configured to drive the matrix circuit over a substrate, comprising:

forming a first oxide semiconductor layer over the substrate in a matrix circuit region and a driver circuit region;

removing the first oxide semiconductor layer from the matrix circuit region by etching; and

forming a second oxide semiconductor layer and a third oxide semiconductor layer, the second oxide semiconductor layer being formed over the first oxide semiconductor layer in the driver circuit region and the third oxide semiconductor layer being formed over the substrate in the matrix circuit region,

wherein a first thin film transistor in the driver circuit region comprises a stack of the first oxide semiconductor layer and the second oxide semiconductor layer, and

wherein a second thin film transistor in the matrix circuit region comprises the third oxide semiconductor layer.

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

wherein electrical resistivity of the first oxide semiconductor layer is lower than electrical resistivity of the second oxide semiconductor layer.

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

wherein the first oxide semiconductor layer comprises a first material,

wherein the second oxide semiconductor layer comprises a second material being different from the first material, and

wherein the third oxide semiconductor layer comprises the second material.

19. A method for manufacturing a semiconductor device which includes a matrix circuit and a driver circuit configured to drive the matrix circuit over a substrate, comprising:

forming a metal thin film over the substrate in a matrix circuit region and a driver circuit region;

removing the metal thin film from the matrix circuit region by etching;

forming a first oxide semiconductor layer over the metal thin film in the driver circuit region and over the substrate in the matrix circuit region; and

forming a second oxide semiconductor layer by performing oxidation treatment on the metal thin film after forming the oxide semiconductor layer,

wherein a first thin film transistor comprises a stack of the first oxide semiconductor layer and the second oxide semiconductor layer in the driver circuit region, and

wherein a second thin film transistor comprises a third oxide semiconductor layer in the matrix circuit region.

20. The method for manufacturing a semiconductor device, according to claim 19,

wherein the oxidation treatment is heat treatment which is performed in any one of an atmosphere containing oxygen, air, and a nitrogen atmosphere.

21. The method for manufacturing a semiconductor device, according to claim 19,

wherein the first oxide semiconductor layer contains at least one of indium, gallium, and zinc.

22. The method for manufacturing a semiconductor device, according to claim 19,

wherein the metal thin film contains at least one of indium, zinc, tin, molybdenum, and tungsten.

23. The method for manufacturing a semiconductor device, according to claim 19,

wherein at least one of elements which are contained in the second oxide semiconductor layer is the same as an element contained in the metal thin film.

24. The method for manufacturing a semiconductor device, according to claim 19,

wherein the metal thin film is formed by any one of a sputtering method, a vacuum vapor deposition method, and a coating method.

25. The method for manufacturing a semiconductor device, according to claim 19,

wherein a thickness of the first oxide semiconductor layer is 30 nm to 150 nm, inclusive.

26. The method for manufacturing a semiconductor device, according to claim 19,

wherein a thickness of the metal thin film is smaller than a thickness of the first oxide semiconductor layer.

27. The method for manufacturing a semiconductor device, according to claim 19,

wherein electrical resistivity of the second oxide semiconductor layer is lower than electrical resistivity of the first oxide semiconductor layer.

28. The method for manufacturing a semiconductor device, according to claim 19,

wherein the first oxide semiconductor layer comprises a first material,

wherein the second oxide semiconductor layer comprises a second material being different from the first material, and

wherein the third oxide semiconductor layer comprises the first material.