초록 ▼

To provide a technique for manufacturing a wiring line having a low resistance and a high heat resistance so as to make an active matrix type display device larger and finer. The wiring line is constructed of a laminated structure of a refractory metal, a low resistance metal and a refractory metal,

To provide a technique for manufacturing a wiring line having a low resistance and a high heat resistance so as to make an active matrix type display device larger and finer. The wiring line is constructed of a laminated structure of a refractory metal, a low resistance metal and a refractory metal, and the wiring line is further protected with an anodized film. As a result, it is possible to form the wiring line having the low resistance and the high heat resistance and to form a contact with an upper line easily.

대표청구항 ▼

What is claimed is: 1. A portable telephone comprising: a voice output unit: a voice input unit; and a display unit, wherein the display unit comprises: a semiconductor film formed over a substrate, the semiconductor film having a channel region, a source region and a drain region; a gate insulatin

What is claimed is: 1. A portable telephone comprising: a voice output unit: a voice input unit; and a display unit, wherein the display unit comprises: a semiconductor film formed over a substrate, the semiconductor film having a channel region, a source region and a drain region; a gate insulating film over the semiconductor film; and a gate electrode formed over the gate insulating film, the gate electrode having a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer, and a third conductive layer on the second conductive layer, wherein a width of the second conductive layer is smaller than those of the first and third conductive layers. 2. A portable telephone according to claim 1, wherein the third conductive layer comprises a valve metal. 3. A portable telephone according to claim 1, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 4. A portable telephone according to claim 1, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 5. A portable book comprising: a display unit; and a control switch, wherein the display unit comprises: a semiconductor film formed over a substrate, the semiconductor film having a channel region, a source region and a drain region; a gate insulating film over the semiconductor film; and a gate electrode formed over the gate insulating film, the gate electrode having a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer, and a third conductive layer on the second conductive layer, wherein a width of the second conductive layer is smaller than those of the first and third conductive layers. 6. A portable book according to claim 5, wherein the third conductive layer comprises a valve metal. 7. A portable book according to claim 5, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 8. A portable book according to claim 5, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 9. A display device comprising: a display unit, wherein the display unit comprises: a semiconductor film formed over a substrate, the semiconductor film having a channel region, a source region and a drain region; a gate insulating film over the semiconductor film; and a gate electrode formed over the gate insulating film, the gate electrode having a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer, and a third conductive layer on the second conductive layer, wherein a width of the second conductive layer is smaller than those of the first and third conductive layers. 10. A display device according to claim 9, wherein the third conductive layer comprises a valve metal. 11. A display device according to claim 9, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 12. A display device according to claim 9, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 13. A portable telephone comprising: a voice output unit: a voice input unit; and a display unit, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film covering the first wiring line; a second wiring line formed over the insulating him and electrically connected with the first wiring line; and a contact hole extending through the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, and wherein the second wiring line is connected with the upper surface of second conductive layer though the contact hole. 14. A portable telephone according to claim 13, wherein the third conductive layer comprises a valve metal. 15. A portable telephone according to claim 13, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 16. A portable telephone according to claim 13, wherein the wiring line is a gate line of a thin film transistor. 17. A portable telephone according to claim 13, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 18. A portable telephone comprising: a voice output unit: a voice input unit; and a display unit, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an oxide film of The first, second and third conductive layers covering side surfaces and an upper surface of The first wiring line; an insulating film covering the oxide film; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film, the third conductive layer and the oxide film, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, and wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole. 19. A portable telephone according to claim 18, wherein the oxide film of the second conductive layer is formed by anodizing. 20. A portable telephone according to claim 18, wherein the third conductive layer comprises a valve metal. 21. A portable telephone according to claim 18, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 22. A portable telephone according to claim 18, wherein the wiring line is a gate line of a thin film transistor. 23. A portable telephone according to claim 18, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 24. A portable telephone comprising: a voice output unit: a voice input unit; and a display unit, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film formed over the first wiring line; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, wherein the second wiring line is connected with the upper surface of second conductive layer though the contact hole, wherein an oxide film is formed on side surfaces of the second conductive layer, and wherein the second conductive layer has a width different from those of the first conductive layer and the third conductive layer. 25. A portable telephone according to claim 24, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 26. A portable telephone according to claim 24, wherein the third conductive layer comprises a material containing a valve metal as its main component. 27. A portable telephone according to claim 24, wherein the first wiring line is a gate line of a thin film transistor. 28. A portable telephone according to claim 24, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 29. A portable telephone comprising: a voice output unit: a voice input unit; and a display unit, wherein the display unit comprises: a p-channel thin film transistor formed over a substrate, the p-channel thin film transistor comprising: a first semiconductor layer having a first channel region, a first source region, and a first drain region; a first gate line footed over the first semiconductor layer with a first gate insulating film interposed therebetween, and an n-channel thin film transistor formed over the substrate, the n-channel thin film transistor comprising: a second semiconductor layer having a second channel region, a second source region, a second drain region, and at least one impurity region between the second channel region and the second source region; a second gate line formed over the second semiconductor layer with a second gate insulating film interposed therebetween; wherein the impurity region partly overlaps the second gate line with the second gate insulating film interposed therebetween, and wherein each of the first and second gate lines includes a multi-layered film comprising a first conductive layer in contact with each of the first and second gate insulating films, a second conductive layer on the first conductive layer and a third conductive layer on the third conductive layer, and wherein the impurity region has a lower impurity concentration than that of the second source region. 30. A portable telephone according to claim 29, wherein the third conductive layer comprises a valve metal. 31. A portable telephone according to claim 29, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 32. A portable telephone according to claim 29, wherein the wiring line is a gate line of a thin film transistor. 33. A portable book comprising: a display unit; and a control switch, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film covering the first wiring line; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, and wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole. 34. A portable book according to claim 33, wherein the third conductive layer comprises a valve metal. 35. A portable book according to claim 33, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 36. A portable book according to claim 33, wherein the wiring line is a gate line of a thin film transistor. 37. A portable book according to claim 33, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 38. A portable book comprising: a display unit; and a control switch, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an oxide film of the first, second and third conductive layers covering side surfaces and an upper surface of the first wiring line; an insulating film covering the oxide film; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film, the third conductive layer and the oxide film, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, and wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole. 39. A portable book according to claim 38, wherein the oxide film of the second conductive layer is formed by anodizing. 40. A portable book according to claim 38, wherein the third conductive layer comprises a valve metal. 41. A portable book according to claim 38, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 42. A portable book according to claim 38, wherein the wiring line is a gate line of a thin film transistor. 43. A portable book according to claim 38, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 44. A portable book comprising: a display unit; and a control switch, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film formed over the first wiring line; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole, wherein an oxide film is formed on side surfaces of the second conductive layer, and wherein the second conductive layer has a width different from those of the first conductive layer and the third conductive layer. 45. A portable book according to claim 44, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 46. A portable book according to claim 44, wherein the third conductive layer comprises a material containing a valve metal as its main component. 47. A portable book according to claim 44, wherein the first wiring line is a gate line of a thin film transistor. 48. A portable book according to claim 44, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 49. A portable book comprising: a display unit; and a control switch, wherein the display unit comprises: a p-channel thin film transistor formed over a substrate, the p-channel thin film transistor comprising: a first semiconductor layer having a first channel region, a first source region, and a first drain region; a first gate line formed over the first semiconductor layer with a first gate insulating film interposed therebetween, and an n-channel thin film transistor formed over the substrate, the n-channel thin film transistor comprising: a second semiconductor layer having a second channel region, a second source region, a second drain region, and at least one impurity region between the second channel region and the second source region; a second gate line formed over the second semiconductor layer with a second gate insulating film interposed therebetween; wherein the impurity region partly overlaps the second gate line with the second gate insulating film interposed therebetween, and wherein each of the first and second gate lines includes a multi-layered film comprising a first conductive layer in contact with each of the first and second gate insulating films, a second conductive layer on the first conductive layer and a third conductive layer on the third conductive layer, and wherein the impurity region has a lower impurity concentration than that of the second source region. 50. A portable book according to claim 49, wherein the third conductive layer comprises a valve metal. 51. A portable book according to claim 49, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 52. A portable book according to claim 49, wherein the wiring line is a gate line of a thin film transistor. 53. A display device comprising: a display unit, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film covering the first wiring line; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending though the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, and wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole. 54. A display device according to claim 53, wherein the third conductive layer comprises a valve metal. 55. A display device according to claim 53, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 56. A display device according to claim 53, wherein the wiring line is a gate line of a thin film transistor. 57. A display device according to claim 53, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 58. A display device comprising: a display unit, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an oxide film of the first, second and third conductive layers covering side surfaces and an upper surface of the first wiring line; an insulating film covering the oxide film; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film, the third conductive layer and the oxide film, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, and wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole. 59. A display device according to claim 58, wherein the oxide film of the second conductive layer is formed by anodizing. 60. A display device according to claim 58, wherein the third conductive layer comprises a valve metal. 61. A display device according to claim 58, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 62. A display device according to claim 58, wherein the wiring line is a gate line of a thin film transistor. 63. A display device according to claim 58, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 64. A display device comprising: a display unit, wherein the display unit comprises: a first wiring line including a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film formed over the first wiring line; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole, wherein an oxide film is formed on side surfaces of the second conductive layer, and wherein the second conductive layer has a width different from those of the first conductive layer and the third conductive layer. 65. A display device according to claim 64, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 66. A display device according to claim 64, wherein the third conductive layer comprises a material containing a valve metal as its main component. 67. A display device according to claim 64, wherein the first wiring line is a gate line of a thin film transistor. 68. A display device according to claim 64, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 69. A display device comprising: a display unit wherein the display unit comprises: a p-channel thin film transistor formed over a substrate, the p-channel thin film transistor comprising: a first semiconductor layer having a first channel region, a first source region, and a first drain region; a first gate line formed over the first semiconductor layer with a first gate insulating film interposed therebetween, and an n-channel thin film transistor formed over the substrate, the n-channel thin film transistor comprising: a second semiconductor layer having a second channel region, a second source region, a second drain region, and at least one impurity region between the second channel region and the second source region; a second gate line formed over the second semiconductor layer with a second gate insulating film interposed therebetween; wherein the impurity region partly overlaps the second gate line with the second gate insulating film interposed therebetween, and wherein each of the first and second gate lines includes a multi-layered film comprising a first conductive layer in contact with each of the first and second gate insulating films, a second conductive layer on the first conductive layer and a third conductive layer on the third conductive layer, and wherein the impurity region has a lower impurity concentration than that of the second source region. 70. A display device according to claim 69, wherein the third conductive layer comprises a valve metal. 71. A display device according to claim 69, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 72. A display device according to claim 69, wherein the wiring line is a gate line of a thin film transistor. 73. A semiconductor device comprising: a thin film transistor comprising a gate electrode, a gate insulating film over the gate electrode, a semiconductor layer over the gate insulating film; a first wiring line including the gate electrode, wherein the first wiring includes a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film covering the first wiring line; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, and wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole. 74. A semiconductor device comprising: a thin film transistor comprising a gate electrode, a gate insulating film over the gate electrode, a semiconductor layer over the gate insulating film; a first wiring line including the gate electrode, wherein the first wiring includes a multi-layered film comprising a first conductive layer, a second conductive layer on the first conductive layer and a third conductive layer on the second conductive layer; an insulating film formed over the first wiring line; a second wiring line formed over the insulating film and electrically connected with the first wiring line; and a contact hole extending through the insulating film and the third conductive layer, wherein an upper surface of the second conductive layer is exposed at a bottom portion of the contact hole, wherein the second wiring line is connected with the upper surface of second conductive layer through the contact hole, and wherein the second conductive layer has a width different from those of the first conductive layer and the third conductive layer. 75. A semiconductor device according to claim 73, wherein the third conductive layer comprises a valve metal. 76. A semiconductor device according to claim 73, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 77. A semiconductor device according to claim 73, wherein the wiring line is a gate line of a thin film transistor. 78. A semiconductor device according to claim 74, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer. 79. A semiconductor device according to claim 74, wherein the third conductive layer comprises a valve metal. 80. A semiconductor device according to claim 74, wherein the second conductive layer comprises a material containing aluminum or titanium as its main component. 81. A semiconductor device according to claim 74, wherein the wiring line is a gate line of a thin film transistor. 82. A semiconductor device according to claim 74, wherein the second conductive layer is in contact with the first conductive layer and the third conductive layer is in contact with the second conductive layer.