Electroluminescent device using nanorods

Abstract

An electroluminescent device may be constructed with a first electrode and a second electrode which are spaced apart from each other and face each other, an inorganic light emitting layer formed between the first and second electrodes, a dielectric layer formed on an inner surface of the second electrode, and a field emission layer which is formed on at least one of an upper or lower surface of the inorganic light emitting layer and which is made from nanorods having a large aspect ratio.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:

FIG. 1 is a cross-sectional view of a contemporary inorganic electroluminescent device;

FIG. 2 is a cross-sectional view of an electroluminescent device constructed as an embodiment of the principles of the present invention;

FIGS. 3A and 3B are scanning electron microscope (SEM) images, made at different resolution scales of 6.00 μm and 600 nm respectively, showing carbon nanotubes (CNTs) formed by a chemical vapor deposition (CVD) method;

FIGS. 4A and 4B are SEM images, made at different resolution scales of 10.0 μm and 3.00 μm respectively, showing CNTs formed using a CNT paste;

FIG. 5 is a cross-sectional view of an electroluminescent device constructed as another embodiment of the principles of the present invention;

FIG. 6 is an SEM image made at a resolution scale of 10.0 μm showing a mixture of 2 wt % ZnO nanowires with a phosphor material; and

FIG. 7 is a two-coordinates graph of driving voltage as a function of the brightness of light obtained from electroluminescent devices including a contemporary electroluminescent device and electroluminescent devices constructed as embodiments of the principles of the present invention.

Claims

1. An electroluminescent device comprising: a first electrode and a second electrode spaced apart from each other and facing each other;an inorganic light emitting layer formed between the first and second electrodes;a dielectric layer formed on an inner surface of the second electrode; anda field emission layer formed on at least one of an upper and lower surface of the inorganic light emitting layer and made from nanorods.

2. The electroluminescent device of claim 1, comprised of the nanorods comprising nanowires.

3. The electroluminescent device of claim 2, comprised of the nanowires being made from ZnO, TiO2, or SiC.

4. The electroluminescent device of claim 2, comprised of the nanowires being aligned perpendicularly to the surface of the inorganic light emitting layer.

5. The electroluminescent device of claim 1, comprised of the nanorods comprising carbon nanotubes (CNTs) aligned perpendicular to the surface of the inorganic light emitting layer.

6. The electroluminescent device of claim 1, comprised of the inorganic light emitting layer being made from at least one of an electroluminescent (EL) phosphor material and a cathode luminescent (CL) phosphor material.

7. The electroluminescent device of claim 1, comprised of the first electrode being made from a transparent conductive material.

8. The electroluminescent device of claim 7, comprised of the transparent conductive material comprising ITO.

9. The electroluminescent device of claim 1, comprised of the second electrode being made from one of a transparent and electrically conductive material or from an electrically conducting metal.

10. The electroluminescent device of claim 1, comprised of the dielectric layer being made from SiO2.

11. The electroluminescent device of claim 1, further comprising a dielectric layer formed on an inner surface of the first electrode.

12. The electroluminescent device of claim 1, comprised of an alternating polarity voltage being applied between the first and second electrodes.

13. An electroluminescent device comprising: a first electrode and a second electrode spaced apart from each other and facing each other;a field emission light emitting layer disposed between the first and second electrodes and made from a mixture of a field emission material comprised of nanorods and an inorganic light emitting material; anda dielectric layer formed on an inner surface of the second electrode.

14. The electroluminescent device of claim 13, comprised of the nanorods comprising nanowires.

15. The electroluminescent device of claim 14, comprised of the nanowires being made from a material selected from the group of ZnO, TiO and SiC.

16. The electroluminescent device of claim 14, comprised of the nanowires being vertically aligned.

17. The electroluminescent device of claim 13, comprised of the nanorods comprising vertically aligned CNTs.

18. The electroluminescent device of claim 13, comprised of the inorganic light emitting layer comprising at least one of an electroluminescent (EL) phosphor material and a cathode luminescent (CL) phosphor material.

19. The electroluminescent device of claim 13, comprised of the first electrode being made from a transparent and electrically conductive material.

20. The electroluminescent device of claim 13, comprised of the second electrode being made from a transparent and electrically conductive material or an electrically conducting metal.

21. The electroluminescent device of claim 13, further comprising a dielectric layer formed on an inner surface of the first electrode.

22. The electroluminescent device of claim 13, comprised of an alternating polarity voltage being applied between the first and second electrodes.

23. The electroluminescent device of claim 13, wherein the amount of the field emission material with respect to the inorganic light emitting material is 0.01 through 10 wt %.