Semiconductor device and fabrication method of the same

• US 6,875,628 B1
• Filed: 03/06/1997
• Issued: 04/05/2005
• Est. Priority Date: 05/26/1993
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Takemura, Yasuhiko, Takayama, Toru, Zhang, Hongyong, Miyanaga, Akiharu
• Primary Examiner(s): Coleman, W. David
• Assistant Examiner(s): NGUYEN, KHIEM D
• Application Number:
  US08/811,742
• Time in Patent Office: 2,952 Days
• Field of Search: 438/30, 438/151, 438/164, 438/166, 438/486, 438/487, 438/162
• US Class Current: 438/30
• CPC Class Codes: H01L 21/02422 Non-crystalline insulating materials, e.g. glass, polymers
• CPC Class Codes: H01L 21/02488 Insulating materials
• CPC Class Codes: H01L 21/02491 Conductive materials
• CPC Class Codes: H01L 21/02496 Layer structure
• CPC Class Codes: H01L 21/02502 consisting of two layers
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02672 using crystallisation enhancing elements
• CPC Class Codes: H01L 21/02678 Beam shaping, e.g. using a mask
• CPC Class Codes: H01L 21/02686 Pulsed laser beam
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1277 using a crystallisation promoting species, e.g. local introduction of Ni catalyst

Abstract

Nickel is introduced to a predetermined region of a peripheral circuit section, other than a picture element section, on an amorphous silicon film to crystallize from that region. After forming gate electrodes and others, sources, drains and channels are formed by doping impurities, and laser is irradiated to improve the crystallization. After that, electrodes/wires are formed. Thereby an active matrix type liquid crystal display whose thin film transistors (TFT) in the peripheral circuit section are composed of the crystalline silicon film whose crystal is grown in the direction parallel to the flow of carriers and whose TFTs in the picture element section are composed of the amorphous silicon film can be obtained.

Claims

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

forming a semiconductor film over a substrate;

disposing a crystallizing promoting material in contact with a selected portion of the semiconductor film;

crystallizing the semiconductor film by heating wherein a crystal grows from said selected portion of the semiconductor film to a second portion of the semiconductor film adjacent to said selected portion;

patterning the crystallized semiconductor film to form an active layer wherein said active layer includes at least a first region and a second region where said first region includes at least a part of the selected portion of the semiconductor film and said second region includes at least a part of the second portion of the semiconductor film;

forming a gate insulating film over the active layer;

forming a gate electrode over the gate insulating film;

forming an insulating film over the gate insulating film; and

forming a wiring over the insulating film,

wherein the wiring is in contact with said first region of the active layer.

2. A method according to claim 1, wherein the crystallization promoting material comprises an element selected from the group consisting of Ni, Fe, Co, Pd and Pt.

3. A method according to claim 1, wherein the heating is performed at a temperature of 450 to 500°

C.

4. A method according to claim 1, wherein the crystallization promoting material is disposed by a spin-coating.

5. A method according to claim 1, wherein the active layer contains the crystallization promoting material at a concentration of 1×

10¹⁵ atoms/cm³ or more.

6. A method according to claim 1, wherein the semiconductor device constitute a driver circuit of an active matrix display device.

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

forming a semiconductor film over a substrate;

disposing a crystallizing promoting material in contact with a selected portion of the semiconductor film;

crystallizing the semiconductor film by heating wherein a crystal grows from said selected portion of the semiconductor film to a second portion of the semiconductor film adjacent to said selected portion;

patterning the crystallized semiconductor film to form an active layer wherein said active layer includes at least a first region and a second region where said first region includes at least a part of the selected portion of the semiconductor film and said second region includes at least a part of the second portion of the semiconductor film;

forming a gate insulating film over the active layer;

forming two gate electrodes over the gate insulating film;

forming an insulating film over the gate insulating film; and

forming a wiring over the insulating film,

wherein the wiring is in contact with said first region of the active layer,

wherein the active layer constitutes a pair of N-channel and P-channel thin film transistors.

8. A method according to claim 7, wherein the crystallization promoting material comprises an element selected from the group consisting of Ni, Fe, Co, Pd and Pt.

9. A method according to claim 7, wherein the heating is performed at a temperature of 450 to 500°

C.

10. A method according to claim 7, wherein the crystallization promoting material is disposed by a spin-coating.

11. A method according to claim 7, wherein the active layer contains the crystallization promoting material at a concentration of 1×

10¹⁵ atoms/cm³ or more.

12. A method according to claim 7, wherein the semiconductor device constitute a driver circuit of an active matrix display device.

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

forming a semiconductor film over a substrate;

disposing a crystallizing promoting material contact with a selected portion of the semiconductor film;

crystallizing the semiconductor film by heating wherein a crystal grows from said selected portion of the semiconductor film to a second portion of the semiconductor film adjacent to said selected portion;

patterning the crystallized semiconductor film to form an active layer wherein said active layer includes at least a first region and a second region where said first region includes at least a part of the selected portion of the semiconductor film and said region includes at least a part of the second portion of the semiconductor film;

forming a gate insulating film over the active layer;

forming a gate electrode over the gate insulating film;

forming an insulating film over the gate insulating film; and

forming a wiring over the insulating film,

wherein the wiring is in contact with said first region of the active layer.

14. A method according to claim 13, wherein the crystallization promoting material comprises an element selected from the group consisting of Ni, Fe, Co, Pd and Pt.

15. A method according to claim 13, wherein the heating is performed at a temperature of 450 to 500°

C.

16. A method according to claim 13, wherein the crystallization promoting material is disposed by a spin-coating.

17. A method according to claim 13, wherein the active layer contains the crystallization promoting material at a concentration of 1×

10¹⁵ atoms/cm³ or more.

18. A method according to claim 13, wherein the semiconductor device constitute a driver circuit of an active matrix display device.

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

a semiconductor film over a substrate;

disposing a crystallizing promoting material in contact with a selected portion of the semiconductor film;

crystallizing the semiconductor film by heating wherein a crystal grows from said selected portion of the semiconductor film to a second portion of the semiconductor film adjacent to said selected portion;

patterning the crystallized semiconductor film to form an active layer wherein said active layer includes at least a first selected portion of the semiconductor film and said second region includes at least a part of the second portion of the semiconductor film;

forming a gate insulating film over the active layer;

forming a gate electrode over the gate insulating film;

forming an insulating film over the gate insulating film; and

forming a wiring over the insulating film,

wherein the wiring is in contact with said first region of the active layer,

wherein the crystals extend along with a direction in which carries of the thin film transistor flow.

20. A method according to claim 19, wherein the crystallization promoting material comprises an element selected from the group consisting of Ni, Fe, Co, Pd and Pt.

21. A method according to claim 19, wherein the heating is performed at a temperature of 450 to 500°

C.

22. A method according to claim 19, wherein the crystallization promoting material is disposed by a spin-coating.

23. A method according to claim 19, wherein the active layer contains the crystallization promoting material at a concentration of 1×

10¹⁵ atoms/cm³ or more.

24. A method according to claim 19, wherein the semiconductor device constitute a driver circuit of an active matrix display device.

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

forming a semiconductor film over a substrate;

disposing a crystallizing promoting material in contact with a selected portion of the semiconductor film;

crystallizing the semiconductor film by heating wherein a crystal grows from said selected portion of the semiconductor film to a second portion of the semiconductor film adjacent to said selected portion;

patterning the crystallized semiconductor film to form an active layer wherein said active layer includes at least a first region and a second region where said first region includes at least a part of the selected portion of the semiconductor film and said second region includes at least a part of the second portion of the semiconductor film;

forming a gate insulating film over the active layer;

forming a gate electrode over the gate insulating film;

forming an insulating film over the gate insulating film; and

forming a wiring over the insulating film,

wherein the wiring is in contact with said first region of the active layer,

wherein the crystals extend along with a direction connecting source and drain regions of the thin film transistor.

26. A method according to claim 25, wherein the crystallization promoting material comprises an element selected from the group consisting of Ni, Fe, Co, Pd and Pt.

27. A method according to claim 25, wherein the heating is performed at a temperature of 450 to 500°

C.

28. A method according to claim 25, wherein the crystallization promoting material is disposed by a spin-coating.

29. A method according to claim 25, wherein the active layer contains the crystallization promoting material at a concentration of 1×

10¹⁵ atoms/cm³ or more.

30. A method according to claim 25, wherein the semiconductor device constitute a driver circuit of an active matrix display device.

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

forming a semiconductor film over a substrate;

disposing a crystallizing promoting material in contact with a selected portion of the semiconductor film;

crystallizing the semiconductor film by heating wherein a crystal grows from said selected portion of the semiconductor film to a second portion of the semiconductor film adjacent to said selected portion;

patterning the crystallized semiconductor film to form an active layer wherein said active layer includes at least a first region and a second region where said first region includes at least a part of the selected portion of the semiconductor film and said second region includes at least a part of the second portion of the semiconductor film;

forming a gate insulating film over the active layer;

forming a gate electrode over the gate insulating film;

forming an insulating film over the gate insulating film; and

forming a wiring over the insulating film,

wherein the wiring is in contact with said first region of the active layer,

wherein the active layer contains the crystallization promoting material at a concentration of 1×

10¹⁹ atoms/cm³ or less.

32. A method according to claim 31, wherein the crystallization promoting material comprises an element selected from the group consisting of Ni, Fe, Co, Pd and Pt.

33. A method according to claim 31, wherein the heating is performed at a temperature of 450 to 500°

C.

34. A method according to claim 31, wherein the crystallization promoting material is disposed by a spin-coating.

35. A method according to claim 31, wherein the active layer contains the crystallization promoting material at a concentration of 1×

10¹⁵ atoms/cm³ or more.

36. A method according to claim 31, wherein the semiconductor device constitute a driver circuit of an active matrix display device.