Semiconductor device and manufacturing method thereof

• US 8,525,173 B2
• Filed: 03/01/2011
• Issued: 09/03/2013
• Est. Priority Date: 05/09/2000
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Lee, Kyoung
• Application Number:
  US13/037,927
• Publication Number:
  US 20110147752A1
• Time in Patent Office: 917 Days
• Field of Search: None
• US Class Current: 257/59
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/1337 Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2203/03 scattering
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48464 the other connecting portion not on the bonding area also being a ball bond, i.e. ball-to-ball
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 25/18 : the devices being of types provided for in two or more different subgroups of the same main group of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N
• CPC Class Codes: H01L 27/12 : the substrate being other than a semiconductor body, e.g. an insulating body
• 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 27/124 : 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 27/1248 : with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 27/1288 : employing particular masking sequences or specially adapted masks, e.g. half-tone mask
• CPC Class Codes: H01L 29/78669 : with inverted-type structure, e.g. with bottom gate
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/07811 : Extrinsic, i.e. with electrical conductive fillers
• CPC Class Codes: H01L 33/0041 : characterised by field-effect operation

Abstract

A means of forming unevenness for preventing specular reflection of a pixel electrode, without increasing the number of process steps, is provided. In a method of manufacturing a reflecting type liquid crystal display device, the formation of unevenness (having a radius of curvature r in a convex portion) in the surface of a pixel electrode is performed by the same photomask as that used for forming a channel etch type TFT, in which the convex portion is formed in order to provide unevenness to the surface of the pixel electrode and give light scattering characteristics.

Claims

1. A liquid crystal display device comprising:

a first substrate;

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring comprises a same material as a material of the gate electrode,

wherein each of the second wiring and the convex portion comprises a same material as a material of the source electrode and the drain electrode,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the convex portion is island-shaped, and

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode.

2. The liquid crystal display device according to claim 1, wherein the light shielding portion is a laminate of color filters.

3. The liquid crystal display device according to claim 1, wherein the first wiring is a capacitor wiring.

4. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

5. The liquid crystal display device according to claim 1, wherein the pixel electrode comprises a conductive film having reflectivity.

6. The liquid crystal display device according to claim 1, wherein the convex portion is electrically connected to the pixel electrode.

7. The liquid crystal display device according to claim 1, wherein the pixel electrode is contact with an upper surface of the convex portion.

8. The liquid crystal display device according to claim 1, wherein the convex portion is completely overlapped with the first wiring.

9. A liquid crystal display device comprising:

a first substrate;

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring comprises a same material as a material of the gate electrode,

wherein each of the second wiring and the convex portion comprises a same material as a material of the source electrode and the drain electrode,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the convex portion is island-shaped,

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode,

wherein an size of the convex portion is 1 to 400 μ

m², and

wherein adjacent convex portions are isolated by 0.1 μ

m or greater.

10. The liquid crystal display device according to claim 9, wherein the light shielding portion is a laminate of color filters.

11. The liquid crystal display device according to claim 9, wherein the first wiring is a capacitor wiring.

12. The liquid crystal display device according to claim 9, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

13. The liquid crystal display device according to claim 9, wherein the pixel electrode comprises a conductive film having reflectivity.

14. The liquid crystal display device according to claim 9, wherein the convex portion is electrically connected to the pixel electrode.

15. The liquid crystal display device according to claim 9, wherein the pixel electrode is contact with an upper surface of the convex portion.

16. The liquid crystal display device according to claim 9, wherein the convex portion is completely overlapped with the first wiring.

17. A liquid crystal display device comprising:

a first substrate;

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a terminal portion comprising a first layer and a second layer over the first substrate, the terminal portion electrically being connected to a flexible printed circuit,

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring comprises a same material as a material of the gate electrode,

wherein each of the second wiring and the convex portion comprises a same material as a material of the source electrode and the drain electrode,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the first layer comprises a same material as a material of the gate electrode, and the second layer comprises a same material as a material of the pixel electrode,

wherein the second layer covers at least one end of the first layer,

wherein the convex portion is island-shaped, and

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode.

18. The liquid crystal display device according to claim 17, wherein the light shielding portion is a laminate of color filters.

19. The liquid crystal display device according to claim 17, wherein the first wiring is a capacitor wiring.

20. The liquid crystal display device according to claim 17, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

21. The liquid crystal display device according to claim 17, wherein the pixel electrode comprises a conductive film having reflectivity.

22. The liquid crystal display device according to claim 17, wherein the convex portion is electrically connected to the pixel electrode.

23. The liquid crystal display device according to claim 17, wherein the pixel electrode is contact with an upper surface of the convex portion.

24. The liquid crystal display device according to claim 17, wherein the convex portion is completely overlapped with the first wiring.

25. A liquid crystal display device comprising:

a first substrate;

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a terminal portion comprising a first layer and a second layer over the first substrate, the terminal portion electrically being connected to a flexible printed circuit,

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring comprises a same material as a material of the gate electrode,

wherein each of the second wiring and the convex portion comprises a same material as a material of the source electrode and the drain electrode,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the first layer comprises a same material as a material of the gate electrode, and the second layer comprises a same material as a material of the pixel electrode,

wherein the second layer covers at least one end of the first layer,

wherein the convex portion is island-shaped,

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode,

wherein an size of the convex portion is 1 to 400 μ

m², and

wherein adjacent convex portions are isolated by 0.1 μ

m or greater.

26. The liquid crystal display device according to claim 25, wherein the light shielding portion is a laminate of color filters.

27. The liquid crystal display device according to claim 25, wherein the first wiring is a capacitor wiring.

28. The liquid crystal display device according to claim 25, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

29. The liquid crystal display device according to claim 25, wherein the pixel electrode comprises a conductive film having reflectivity.

30. The liquid crystal display device according to claim 25, wherein the convex portion is electrically connected to the pixel electrode.

31. The liquid crystal display device according to claim 25, wherein the pixel electrode is contact with an upper surface of the convex portion.

32. The liquid crystal display device according to claim 25, wherein the convex portion is completely overlapped with the first wiring.

33. A liquid crystal display device comprising:

a first substrate,

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring and the gate electrode are concurrently formed by a first same patterning process step,

wherein the second wiring, the convex portion, the source electrode, and the drain electrode are concurrently formed by a second same patterning process step,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the convex portion is island-shaped, and

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode.

34. The liquid crystal display device according to claim 33, wherein the light shielding portion is a laminate of color filters.

35. The liquid crystal display device according to claim 33, wherein the first wiring is a capacitor wiring.

36. The liquid crystal display device according to claim 33, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

37. The liquid crystal display device according to claim 33, wherein the pixel electrode comprises a conductive film having reflectivity.

38. The liquid crystal display device according to claim 33, wherein the convex portion is electrically connected to the pixel electrode.

39. The liquid crystal display device according to claim 33, wherein the pixel electrode is contact with an upper surface of the convex portion.

40. The liquid crystal display device according to claim 33, wherein the convex portion is completely overlapped with the first wiring.

41. A liquid crystal display device comprising:

a first substrate,

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring and the gate electrode are concurrently formed by a first same patterning process step,

wherein the second wiring, the convex portion, the source electrode, and the drain electrode are concurrently formed by a second same patterning process step,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the convex portion is island-shaped,

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode,

wherein an size of the convex portion is 1 to 400 μ

m², and

wherein adjacent convex portions are isolated by 0.1 μ

m or greater.

42. The liquid crystal display device according to claim 41, wherein the light shielding portion is a laminate of color filters.

43. The liquid crystal display device according to claim 41, wherein the first wiring is a capacitor wiring.

44. The liquid crystal display device according to claim 41, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

45. The liquid crystal display device according to claim 41, wherein the pixel electrode comprises a conductive film having reflectivity.

46. The liquid crystal display device according to claim 41, wherein the convex portion is electrically connected to the pixel electrode.

47. The liquid crystal display device according to claim 41, wherein the pixel electrode is contact with an upper surface of the convex portion.

48. The liquid crystal display device according to claim 42, wherein the convex portion is completely overlapped with the first wiring.

49. A liquid crystal display device comprising:

a first substrate;

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a terminal portion comprising a first layer and a second layer over the first substrate, the terminal portion electrically being connected to a flexible printed circuit;

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring, the first layer and the gate electrode are concurrently formed by a first patterning process step,

wherein the second wiring, the convex portion, the source electrode, and the drain electrode are concurrently formed by a second pattering process step,

wherein the second layer and the pixel electrode are concurrently formed by a third patterning process step,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the second layer covers at least one end of the first layer,

wherein the convex portion is island-shaped, and

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode.

50. The liquid crystal display device according to claim 49, wherein the light shielding portion is a laminate of color filters.

51. The liquid crystal display device according to claim 49, wherein the first wiring is a capacitor wiring.

52. The liquid crystal display device according to claim 49, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

53. The liquid crystal display device according to claim 49, wherein the pixel electrode comprises a conductive film having reflectivity.

54. The liquid crystal display device according to claim 49, wherein the convex portion is electrically connected to the pixel electrode.

55. The liquid crystal display device according to claim 49, wherein the pixel electrode is contact with an upper surface of the convex portion.

56. The liquid crystal display device according to claim 49, wherein the convex portion is completely overlapped with the first wiring.

57. A liquid crystal display device comprising:

a first substrate;

a thin film transistor over the first substrate, the thin film transistor comprising;

a gate electrode over the first substrate;

a semiconductor film having a channel forming region over the gate electrode;

a source electrode and a drain electrode over the semiconductor film;

a pixel electrode electrically connected to the thin film transistor;

a first wiring over the first substrate;

a second wiring over the first wiring;

a convex portion overlapped with the first wiring;

a terminal portion comprising a first layer and a second layer over the first substrate, the terminal portion electrically being connected to a flexible printed circuit;

a second substrate opposite to the first substrate; and

a light shielding portion located between the thin film transistor and the second substrate,

wherein the first wiring, the first layer and the gate electrode are concurrently formed by a first patterning process step,

wherein the second wiring, the convex portion, the source electrode, and the drain electrode are concurrently formed by a second pattering process step,

wherein the second layer and the pixel electrode are concurrently formed by a third patterning process step,

wherein the second wiring has a lamination structure comprising at least two conductive layers,

wherein the second layer covers at least one end of the first layer,

wherein the convex portion is island-shaped,

wherein the channel forming region overlaps with the light shielding portion, and does not overlap with the pixel electrode,

wherein a size of the convex portion is 1 to 400 μ

m², and

wherein adjacent convex portions are isolated by 0.1 μ

m or greater.

58. The liquid crystal display device according to claim 57, wherein the light shielding portion is a laminate of color filters.

59. The liquid crystal display device according to claim 57, wherein the first wiring is a capacitor wiring.

60. The liquid crystal display device according to claim 57, wherein the liquid crystal display device is a reflecting type liquid crystal display device.

61. The liquid crystal display device according to claim 57, wherein the pixel electrode comprises a conductive film having reflectivity.

62. The liquid crystal display device according to claim 57, wherein the convex portion is electrically connected to the pixel electrode.

63. The liquid crystal display device according to claim 57, wherein the pixel electrode is contact with an upper surface of the convex portion.

64. The liquid crystal display device according to claim 57, wherein the convex portion is completely overlapped with the first wiring.