Claims
- 1. A combined substrate and dielectric layer component for use in an EL laminate, comprising:
a substrate providing a rear electrode; and a thick film dielectric layer formed on the substrate from a pressed, sintered ceramic material having, compared to an unpressed, sintered dielectric layer of the same composition, improved dielectric strength, reduced porosity and uniform luminosity in an EL laminate.
- 2. The combined substrate and dielectric layer component as set forth in claim 1, formed on a rigid substrate providing a rear electrode.
- 3. The combined substrate and dielectric layer component as set forth in claim 2, wherein the dielectric layer has been pressed by cold isostatic pressing to reduce the thickness, after sintering, by about 20 to 50%.
- 4. The combined substrate and dielectric layer component as set forth in claim 3, wherein the pressed ceramic material has a reduced thickness, after sintering, of 30 to 40%.
- 5. The combined substrate and dielectric layer component as set forth in claim 4, wherein the pressed ceramic material has a thickness, after sintering, of between 10 and 50 μm.
- 6. The combined substrate and dielectric layer component as set forth in claim 4, wherein the pressed ceramic material has a thickness, after sintering, of between 10 and 20 μm.
- 7. The combined substrate and dielectric layer component as set forth in claim 6, wherein the ceramic material is a ferroelectric ceramic material having a dielectric constant greater than 500.
- 8. The combined substrate and dielectric layer component as set forth in claim 7, wherein the ceramic material has a perovskite crystal structure.
- 9. The combined substrate and dielectric layer component as set forth in claim 8, wherein the ceramic material is selected from the group consisting of one or more of BaTiO3, PbTiO3, PMN and PMN—PT.
- 10. The combined substrate and dielectric layer component as set forth in claim 8, wherein the ceramic material is selected from the group consisting of BaTiO3, PbTiO3, PMN and PMN—PT.
- 11. The combined substrate and dielectric layer component as set forth in claim 8, wherein the ceramic material is PMN—PT.
- 12. The combined substrate and dielectric layer component as set forth in claim 9, wherein a second ceramic material is formed on the pressed, sintered dielectric layer to further smooth the surface.
- 13. The combined substrate and dielectric layer component as set forth in claim 10, wherein a second ceramic material is formed on the pressed, sintered dielectric layer to further smooth the surface.
- 14. The combined substrate and dielectric layer component as set forth in claim 11, wherein a second ceramic material is formed on the pressed, sintered dielectric layer to further smooth the surface.
- 15. The combined substrate and dielectric layer component as set forth in claim 13, wherein the second ceramic material is a ferroelectric ceramic material deposited by sol gel techniques followed by heating to convert to a ceramic material.
- 16. The combined substrate and dielectric layer component as set forth in claim 15, wherein the second ceramic material has a dielectric constant of at least 20 and a thickness of at least about 1 μm.
- 17. The combined substrate and dielectric layer component as set forth in claim 16, wherein the second ceramic material has a dielectric constant of at least 100.
- 18. The combined substrate and dielectric layer component as set forth in claim 17, wherein the second ceramic material has a thickness in the range of 1 to 3 μm.
- 19. The combined substrate and dielectric layer component as set forth in claim 18, wherein the second ceramic material is a ferroelectric ceramic material having a perovskite crystal structure.
- 20. The combined substrate and dielectric layer component as set forth in claim 19, wherein the second ceramic material is lead zirconium titanate or lead lanthanum zirconate titanate.
- 21. The combined substrate and dielectric layer component as set forth in claim 1, wherein the combined substrate and dielectric layer component is formed on a rigid substrate, on which is formed the rear electrode.
- 22. The combined substrate and dielectric layer component as set forth in claim 14, wherein the combined substrate and dielectric layer component is formed on a rigid substrate, on which is formed the rear electrode.
- 23. The combined substrate and dielectric layer component as set forth in claim 20, wherein the combined substrate and dielectric layer component is formed on a rigid substrate, on which is formed the rear electrode.
- 24. The combined substrate and dielectric layer component as set forth in claim 23, wherein the substrate and the rear electrode are formed from materials which can withstand temperatures of about 850□ C.
- 25. The combined substrate and dielectric layer component as set forth in claim 24, wherein the substrate is an alumina sheet.
- 26. The combined substrate and dielectric layer component as set forth in claim 1, which further comprises, a diffusion barrier layer above the dielectric layer, which diffusion barrier layer is composed of a metal-containing electrically insulating binary compound that is chemically compatible with any adjacent layers and which is precisely stoichiometric.
- 27. The combined substrate and dielectric layer component as set forth in claim 13, which further comprises, a diffusion barrier layer or above the second ceramic material, which diffusion barrier layer is composed of a metal-containing electrically insulating binary compound that is chemically compatible with any adjacent layers and which is precisely stoichiometric.
- 28. The combined substrate and dielectric layer component as set forth in claim 23, which further comprises, a diffusion barrier layer above the second ceramic material, which diffusion barrier layer is composed of a metal-containing electrically insulating binary compound that is chemically compatible with any adjacent layers and which is precisely stoichiometric.
- 29. The combined substrate and dielectric layer component as set forth in claim 28, wherein the diffusion barrier layer is formed from a compound which differs from its precise stoichiometric composition by less than 0.1 atomic percent.
- 30. The combined substrate and dielectric layer component as set forth in claim 29, wherein the diffusion barrier layer is formed from alumina, silica, or zinc sulfide.
- 31. The combined substrate and dielectric layer component as set forth in claim 29, wherein the diffusion barrier is formed from alumina.
- 32. The combined substrate and dielectric layer component as set forth in claim 30, wherein the diffusion barrier has a thickness of 100 to 1000 Å.
- 33. The combined substrate and dielectric layer component as set forth in claim 31, wherein the diffusion barrier has a thickness of 100 to 1000 Å.
- 34. The combined substrate and dielectric layer component as set forth in claim 1, which further comprises, an injection layer above the dielectric layer to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 35. The combined substrate and dielectric layer component as set forth in claim 14, which further comprises, an injection layer above the second ceramic material to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 36. The combined substrate and dielectric layer component as set forth in claim 23, which further comprises, an injection layer above the second ceramic material to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 37. The combined substrate and dielectric layer component as set forth in claim 28, which further comprises, an injection layer above the diffusion barrier layer to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 38. The combined substrate and dielectric layer component as set forth in claim 34, wherein the injection layer is formed from a material which has greater than 0.5% atomic deviation from its stoichiometric composition.
- 39. The combined substrate and dielectric layer component as set forth in claim 38, wherein the injection layer is formed from hafnia or yttria.
- 40. The combined substrate and dielectric layer component as set forth in claim 39, wherein the injection layer has a thickness of 100 to 1000 Å.
- 41. The combined substrate and dielectric layer component as set forth in claim 38, wherein the injection layer is hafnia with a zinc sulfide phosphor, and wherein a diffusion barrier layer of zinc sulfide is used with a strontium sulfide phosphor.
- 42. The combined substrate and dielectric layer component as set forth in claim 40, wherein the injection layer is hafnia with a zinc sulfide phosphor, and wherein a diffusion barrier layer of zinc sulfide is used with a strontium sulfide phosphor.
- 43. An EL laminate, comprising:
a planar phosphor layer; a front and rear planar electrode on either side of the phosphor layer; a rear substrate providing the rear electrode, the rear substrate having sufficient rigidity to support the laminate; and a thick film dielectric layer on the rigid substrate providing the rear electrode, the thick film dielectric layer being formed from a pressed, sintered ceramic material having, compared to an unpressed, sintered dielectric layer of the same composition, improved dielectric strength, reduced porosity and uniform luminosity in an EL laminate.
- 44. The EL laminate as set forth in claim 43, formed on a rigid substrate providing a rear electrode.
- 45. The EL laminate as set forth in claim 43, wherein the dielectric layer has been pressed by cold isostatic pressing to reduce the thickness, after sintering, by about 20 to 50%.
- 46. The EL laminate as set forth in claim 44, wherein the dielectric layer has been pressed by cold isostatic pressing to reduce the thickness, after sintering, by about 20 to 50%.
- 47. The EL laminate as set forth in claim 46, wherein the pressed ceramic material has a reduced thickness, after sintering, of 30 to 40%.
- 48. The EL laminate as set forth in claim 47, wherein the pressed ceramic material has a thickness, after sintering, of between 10 and 50 μm.
- 49. The EL laminate as set forth in claim 47, wherein the pressed ceramic material has a thickness, after sintering, of between 10 and 20 μm.
- 50. The EL laminate as set forth in claim 49, wherein the ceramic material is a ferroelectric ceramic material having a dielectric constant greater than 500.
- 51. The EL laminate as set forth in claim 50, wherein the ceramic material has a perovskite crystal structure.
- 52. The EL laminate as set forth in claim 51, wherein the ceramic material is selected from the group consisting of one or more of BaTiO3, PbTiO3, PMN and PMN—PT.
- 53. The EL laminate as set forth in claim 51, wherein the ceramic material is selected from the group consisting of BaTiO3, PbTiO3, PMN and PMN—PT.
- 54. The EL laminate as set forth in claim 51, wherein the ceramic material is PMN—PT.
- 55. The EL laminate as set forth in claim 52, wherein a second ceramic material is formed on the pressed, sintered dielectric layer to further smooth the surface.
- 56. The EL laminate as set forth in claim 53, wherein a second ceramic material is formed on the pressed, sintered dielectric layer to further smooth the surface.
- 57. The EL laminate as set forth in claim 54, wherein a second ceramic material is formed on the pressed, sintered dielectric layer to further smooth the surface.
- 58. The EL laminate as set forth in claim 56, wherein the second ceramic material is a ferroelectric ceramic material deposited by sol gel techniques followed by heating to convert to a ceramic material.
- 59. The EL laminate as set forth in claim 58, wherein the second ceramic material has a dielectric constant of at least 20 and a thickness of at least about 1 μm.
- 60. The EL laminate as set forth in claim 59, wherein the second ceramic material has a dielectric constant of at least 100.
- 61. The EL laminate as set forth in claim 60, wherein the second ceramic material has a thickness in the range of 1 to 3 μm.
- 62. The EL laminate as set forth in claim 61, wherein the second ceramic material is a ferroelectric ceramic material having a perovskite crystal structure.
- 63. The EL laminate as set forth in claim 62, wherein the second ceramic material is lead zirconium titanate or lead lanthanum zirconate titanate.
- 64. The EL laminate as set forth in claim 43, wherein the EL laminate is formed on a rigid substrate, on which is formed the rear electrode.
- 65. The EL laminate as set forth in claim 56, wherein the EL laminate is formed on a rigid substrate, on which is formed the rear electrode.
- 66. The EL laminate as set forth in claim 63, wherein the EL laminate is formed on a rigid substrate, on which is formed the rear electrode.
- 67. The EL laminate as set forth in claim 66, wherein the substrate and the rear electrode are formed from materials which can withstand temperatures of about 850□ C.
- 68. The EL laminate as set forth in claim 67, wherein the substrate is an alumina sheet.
- 69. The EL laminate as set forth in claim 43, which further comprises, a diffusion barrier layer above the dielectric layer, which diffusion barrier layer is composed of a metal-containing electrically insulating binary compound that is chemically compatible with any adjacent layers and which is precisely stoichiometric.
- 70. The EL laminate as set forth in claim 56, which further comprises, a diffusion barrier layer above the second ceramic material, which diffusion barrier layer is composed of a metal-containing electrically insulating binary compound that is chemically compatible with any adjacent layers and which is precisely stoichiometric.
- 71. The EL laminate as set forth in claim 66, which further comprises, a diffusion barrier layer above the second ceramic material, which diffusion barrier layer is composed of a metal-containing electrically insulating binary compound that is chemically compatible with any adjacent layers and which is precisely stoichiometric.
- 72. The EL laminate as set forth in claim 71, wherein the diffusion barrier layer is formed from a compound which differs from its precise stoichiometric composition by less than 0.1 atomic percent.
- 73. The EL laminate as set forth in claim 72, wherein the diffusion barrier layer is formed from alumina, silica, or zinc sulfide.
- 74. The EL laminate as set forth in claim 72, wherein the diffusion barrier is formed from alumina.
- 75. The EL laminate as set forth in claim 73, wherein the diffusion barrier has a thickness of 100 to 1000 Å.
- 76. The EL laminate as set forth in claim 74, wherein the diffusion barrier has a thickness of 100 to 1000 Å.
- 77. The EL laminate as set forth in claim 43, which further comprises, an injection layer above the dielectric layer to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 78. The EL laminate as set forth in claim 56, which further comprises, an injection layer above the second ceramic material to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 79. The EL laminate as set forth in claim 66, which further comprises, an injection layer above the second ceramic material to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 80. The EL laminate as set forth in claim 71, which further comprises, an injection layer above the diffusion barrier layer to provide a phosphor interface, composed of a binary, dielectric material which is non-stoichiometric in its composition and having electrons in a range of energy for injection into the phosphor layer.
- 81. The EL laminate as set forth in claim 77, wherein the injection layer is formed from a material which has greater than 0.5% atomic deviation from its stoichiometric composition.
- 82. The EL laminate as set forth in claim 81, wherein the injection layer is formed from hafnia or yttria.
- 83. The EL laminate as set forth in claim 82, wherein the injection layer has a thickness of 100 to 1000 Å.
- 84. The EL laminate as set forth in claim 81, wherein the injection layer is hafnia with a zinc sulfide phosphor, and wherein a diffusion barrier layer of zinc sulfide is used with a strontium sulfide phosphor.
- 85. The EL laminate as set forth in claim 83, wherein the injection layer is hafnia with a zinc sulfide phosphor, and wherein a diffusion barrier layer of zinc sulfide is used with a strontium sulfide phosphor.
- 86. The combined substrate and dielectric layer component as set forth in claim 4, wherein the pressed ceramic material has a thickness, after sintering, sufficient to prevent dielectric breakdown during operation as determined by the equation d2=V/S, wherein d2 is the thickness of the dielectric layer and V is the maximum applied voltage.
- 87. The combined substrate and dielectric layer component as set forth in claim 4, wherein d2 is 10 μm or greater.
- 88. The EL laminate as set forth in claim 47, wherein the pressed ceramic material is has a thickness, after sintering, sufficient to prevent dielectric breakdown during operation as determined by the equation d2=V/S, wherein d2 is the thickness of the dielectric layer and V is the maximum applied voltage.
- 89. The combined substrate and dielectric layer component as set forth in claim 4, wherein d2 is 10 μm or greater.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser. No. 09/540,288 filed Mar. 31, 2000, which, in turn, claims priority to U.S. provisional application No. 60/134,299, filed May 14, 1999, all of which are incorporated by reference in their entirety herein.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60134299 |
May 1999 |
US |
Divisions (1)
|
Number |
Date |
Country |
Parent |
09540288 |
Mar 2000 |
US |
Child |
10640789 |
Aug 2003 |
US |