Electric field light-emitting device

• US 5,275,967 A
• Filed: 08/17/1992
• Issued: 01/04/1994
• Est. Priority Date: 12/27/1988
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ikoma, Keiko, Kurihara, Noriko, Taniguchi, Yasushi, Hirabayashi, Keiji
• Primary Examiner(s): Hearn, Brian E.
• Assistant Examiner(s): Picardat, Kevin M.
• Application Number:
  US07/929,916
• Time in Patent Office: 505 Days
• Field of Search: 437/180, 437/184, 437/186, 437/127, 437/23, 437/130, 437/131, 437/132, 148/33.4, 257/77, 257/103
• US Class Current: 438/22
• CPC Class Codes: C09K 11/65 containing carbon in organic compounds C09K11/06
• CPC Class Codes: H05B 33/12 Light sources with substantially two-dimensional radiating surfaces
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: H05B 33/18 characterised by the nature or concentration of the activator
• CPC Class Codes: H05B 33/22 characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers
• CPC Class Codes: H05B 33/26 characterised by the composition or arrangement of the conductive material used as an electrode

Abstract

An electric field effect light emitting device comprises a light emitting layer consisting of a diamond-like carbon film containing oxygen.

Claims

1. A method for producing an electric field effect light-emitting device comprising the steps of:

forming a first conductive film on a supporting body;

forming a light-emitting layer comprising a diamond-like carbon film including an oxygen atom at a concentration not greater than 5 atomic percent on said first conductive film; and

forming a second conductive film on said light-emitting layer.

2. A method according to claim 1, wherein the oxygen atom is included in a raw material gas used in forming the light-emitting layer.

3. A method according to claim 1, wherein after forming the diamond-like carbon film light-emitting layer, the oxygen atom is introduced by oxidization in an atmosphere including oxygen or within a plasma.

4. A method according to claim 1, wherein said light-emitting layer includes a light-emitting center element.

5. A method according to claim 4, wherein the light-emitting center element is contained in the amount of 0.1-3 wt. %.

6. A method according to claim 4, wherein the light-emitting center element is selected from the group consisting of B, Te, As, Au, Mg, P, Sb, Si, Ta, N, halide, sulfide and oxide.

7. A method according to claim 4, wherein the light-emitting center element is selected from the group consisting of Tl, Ba, Li, Cd, Cs, In, Ra, S, Sr, Ti, Zn, Ca, Ce, Co, Cr, Fe, Ga, K, Mn, Nb, Os, Pb, Rb, Rh, Sc, Th, V, W, Y, halide, sulfide and oxide.

8. A method according to claim 4, wherein the light-emitting center element is selected from the group consisting of Ag, Be, Bi, Cu, Ge, Hg, Pt, Re, Zr, Al, Ir, Ni, Ru, Sn, Tb, halide, sulfide and oxide.

9. A method according to claim 4, wherein the light-emitting center element is included in the raw material used in forming the light-emitting layer.

10. A method for producing an electric field effect light-emitting device comprising the steps of:

forming a first conductive layer on a supporting body;

forming an insulating layer on the first conductive layer;

forming a light-emitting layer comprising a single crystalline or monocrystalline diamond film including element constituting a light emission center on the insulating layer; and

forming a second conductive film on the light emission layer.

11. A method according to claim 10, wherein the element constituting the light emission center of a concentration 5×

10^-2 -1×

10^-5 per carbon atom is included in the light-emitting layer.

12. A method according to claim 10, wherein the element constituting the light emission center is selected from the group consisting of B, Te, As, Au, Mg, P, Sb, Si, Ta, N. halide, sulfide and oxide.

13. A method according to claim 10, wherein the element constituting the light emission center is selected from the group consisting of Tl, Ba, Li, Cd, Cs, In, Ra, S, Sr, Ti, Zn, Ca, Ce, Co, Cr, Fe, Ga, K, Nm, Nb, Os, Pb, Rb, Rh, Sc, Th, V, W, Y, halide, sulfide and oxide.

14. A method according to claim 10, wherein the element constituting the light emission center is selected from the group consisting of Ag, Be, Bi, Cu, Ge, Hg, Pt, Re, Zr, Al, Ir, Ni, Ru, Sn, Tb, halide, sulfide and oxide.

15. A method according to claim 10, wherein said insulating layer is formed using a material selected from the group consisting of HfO₂, Si₃ N₄, al₂ O₃, Ta₂ O₅, PbTiO₃, BaTa₂ O₆ and SrTiO₃.

16. A method according to claim 10, further comprising the step forming a protective layer on the second conductive layer.

17. A method according to claim 10, wherein the atom constituting the light emission center is nonuniformly distributed in the cross-section of the insulating layer.

18. A method according to claim 10, wherein the atom constituting the light emission center is uniformly distributed in the cross-section of the insulating layer.

19. A method according to claim 10, wherein the element constituting the light emission center is distributed in a relatively higher density at the side of the insulating layer adjacent the conductive member.

20. A method for producing an electric field effect light-emitting device comprising the steps of:

forming a first conductive layer on a supporting body;

forming a light-emitting layer comprising a polycrystalline or monocrystalline diamond-thin film including an element constituting a light emission center on the first conductive layer;

forming an insulting layer on the light-emitting layer; and

forming a second conductive film on the insulating layer.

21. A method according to claim 20, wherein the element constituting the light emission center of concentration 5×

10^-2 -1×

10^-5 per carbon atom is included in the light-emitting layer.

22. A method according to claim 20, wherein the element constituting the light emission center is selected from the group consisting of B, Te, As, Au, Mg, P, Sb, Si, Ta, N. halide, sulfide and oxide.

23. A method according to claim 20, wherein the element constituting the light emission center is selected from the group consisting of Tl, Ba, Li, Cd, Cs, In, Ra, S, Sr, Ti, Zn, Ca, Ce, Cu, Cr, Fe, Ga, K, Mn, Nb, Os, Pb, Rb, Rh, Sc, Th, V, W, Y, halide, sulfide and oxide.

24. A method according to claim 20, wherein the element constituting the light emission center is selected from the group consisting of Ag, Be, Bi, Cu, Ge, Hg, Pt, Re, Zr, Al, Ir, Ni, Ru, Sn, Tb, halide, sulfide and oxide.

25. A method according to claim 20, wherein the light emission layer is formed after forming the insulating layer on the first conductive layer.

26. A method according to claim 25, wherein the insulating layer between the light emission layer and the first conductive layer and the insulating layer between the light emission layer and the second conductive film have different thicknesses.

27. A method according to claim 26, wherein the insulating layer is formed using a material selected from the group consisting of HfO₂, Si₃ N₄, Al₂ O₃, Ta₂ O₅, PbTiO₃, BaTa₂ O₆ and SrTiO₃.

28. A method according to claim 20, further comprising the step of forming a protective layer on the second conductive layer.

29. A method according to claim 20, wherein the atom constituting the light emission center is nonuniformly distributed in the cross-section of the insulating layer.

30. A method according to claim 26, wherein the atom constituting the light emission center is uniformly distributed in the cross-section of the insulating layer.

31. A method according to claim 29, wherein the atom constituting the light emission center is distributed in a higher concentration at the side of the insulating layer adjacent the conductive member.

32. A method according to claim 20, wherein the light emission layer is formed by a vapor phase growth process.

33. A method according to claim 32, wherein the vapor phase growth process is a microwave CVD, a heated filament CVD, a plasma jet or ECR plasma process.