Functional device

Abstract

A functional device having, on a substrate, a pair of electrodes, a functional layer which is sandwiched between the electrodes and has an output that varies in accordance with an applied electric current, and a terminal arranged to apply an electric current to at least one of the electrodes, wherein an insulator is arranged between the electrodes and the density of the insulator decreases as the distance from the terminal increases, or wherein at least one of the electrodes has a notch section, and the ratio of the area of the notch section to the area of the electrode decreases as the distance from the terminal increases. This is an improved functional device which is excellent in production suitability and gives a uniform in-plane output, and can be rendered, in particular, an organic electroluminescence device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are each a schematic view of a functional device according to a first embodiment of the invention.

FIG. 2 is a schematic view showing one density pattern of an insulator on a cathode electrode.

FIG. 3 is a schematic view showing a relationship between the distance from an anode terminal and the ratio of density of an insulator in a functional device.

FIG. 4 is a schematic view showing another density pattern of the insulator.

FIG. 5 is a schematic view showing still another density pattern of the insulator.

FIG. 6 is a measurement chart of the luminance unevenness of a comparative organic EL device having no insulating layer.

FIG. 7 is a measurement chart of the luminance unevenness of an organic EL device of the invention having an insulator having a density distribution.

FIGS. 8A and 8B are each a schematic view of a functional device according to a second embodiment of the invention.

FIG. 9 is a schematic view showing a pattern wherein a notch section is formed in an anode electrode.

FIG. 10 is a schematic view showing a relationship between the light emission area and the distance from an anode terminal in a functional device of the invention.

FIG. 11 is a schematic view showing another notch pattern in an anode electrode.

FIG. 12 is a schematic view showing still another notch pattern in an anode electrode.

FIG. 13 is a schematic view showing a notch pattern formed in a cathode electrode.

FIG. 14 is a schematic view showing another notch pattern formed in the cathode electrode.

FIG. 15 is a schematic view showing still another notch pattern formed in the cathode electrode.

FIG. 16 is a measurement chart of the luminance unevenness of a comparative organic device having no notch section.

FIG. 17 is a measurement chart of the luminance unevenness of an organic EL device of the invention having a notch section.

Claims

1. A functional device, comprising, on a substrate, a pair of electrodes, a functional layer which is sandwiched between the electrodes and has an output that varies in accordance with an applied electric current, and a terminal arranged to apply an electric current to at least one of the electrodes, wherein an insulator is arranged between the electrodes and the density of the insulator gradually decreases as the distance from the terminal increases.

2. The functional device according to claim 1, wherein the insulator forms a discontinuous phase.

3. The functional device according to claim 2, wherein in a layer comprising the insulator, the insulator forms the discontinuous phase and an electroconductive material forms a continuous phase.

4. The functional device according to claim 1, wherein at least one of the electrodes is formed as a stripe.

5. The functional device according to claim 1, wherein the functional layer comprises an organic electroluminescent material.

6. The functional device according to claim 1, wherein the insulator is an organic material or an inorganic material having an electric resistance of 100Ω or more.

7. The functional device according to claim 6, wherein the insulator is a photosensitive resin or a thermosetting resin.

8. The functional device according to claim 6, wherein the insulator is selected from the group consisting of silicon nitride, silicon oxynitride, silicon oxide, and silicon carbide.

9. The functional device according to claim 1, wherein the density distribution of the insulator is formed by varying the number of portions and/or the area of the insulator.

10. A functional device, comprising, on a substrate, a pair of electrodes, a functional layer which is sandwiched between the electrodes and has an output that varies in accordance with an applied electric current, and a terminal arranged to apply an electric current to at least one of the electrodes, wherein at least one of the electrodes has a notch section, and the ratio of the area of the notch section to the area of the electrode decreases as the distance from the terminal increases.

11. The functional device according to claim 10, wherein at least one of the electrodes is formed as a stripe.

12. The functional device according to claim 11, wherein one of the electrodes is formed as a stripe and the other is planar, and the notch section is formed in the planar electrode.

13. The functional device according to claim 12, wherein a plurality of stripe-form electrodes are arranged, and a plurality of notch sections are arranged in the planar electrode so as to correspond to the plural arrangement of the stripe-form electrodes.

14. The functional device according to claim 11, wherein the notch section is formed in the stripe-form electrode.

15. The functional device according to claim 14, wherein a plurality of the notch sections are arranged in the stripe-form electrode.

16. The functional device according to claim 10, wherein the functional layer comprises an organic electroluminescent material.