JPH0373991A - Thin-film el display panel - Google Patents

Abstract

PURPOSE:To improve the reliability by embedding the external terminal lead-out conductive terminal of a thin-film EL element in cover glass. CONSTITUTION:The lead-out conductive terminal 40 for the external terminal 38 of the thin-film EL element 22 is embedded in the cover glass 28. Electrode lead-out flexible leads 36 of the thin-film EL element 22 are formed by adhering external leads 38 of copper foil, etc., on a plastic film 37 in stripes. End parts of corresponding leads 38 are connected electrically with a soldering or mechanically or terminal parts 34 and 35 formed on the peripheral part of a glass substrate 21. Consequently, a defect in electric feeding due to a disconnection of a terminal lead-out extended part is precluded and the reliability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thin film EL display panel, and particularly to a matrix thin 11iE display panel for displaying various information.
This invention relates to an L display panel.

[Conventional technology]

Matrix type thin film EL display panels generally have a glass package structure. An example of its structure will be explained with reference to FIGS. 4(a) and 5(b) and FIGS. 5(a) and 5(b).

Note that FIG. 4(a) is a sectional view in the X direction, and FIG. 4(b) is a sectional view in the Y direction orthogonal to the X direction.

In FIGS. 4(a) and 4(b), reference numeral 1 indicates a light-transmitting glass substrate, and reference numeral 2 indicates a matrix type thin film EL element formed on the glass substrate 1. In FIG. In the thin film EL element 2, 3 is a large number of striped transparent electrodes formed on the glass substrate 1 by vapor deposition or sputtering at a predetermined pitch along the X direction, and 4 covers the transparent electrode 3. Y2O3
5 is a light emitting layer such as ZnS:Mn laminated on the first dielectric layer 4, 6 is a transparent second dielectric layer such as Y2O covering the light emitting layer 5. The dielectric layer 7 is a back electrode made of an A1 vapor-deposited film formed on the second dielectric layer 6 in the form of a large number of stripes at a predetermined pitch along the Y direction. Reference numeral 8 denotes an inverted dish-shaped cover glass that is fixed onto the glass substrate 1 via an adhesive 9 such as epoxy resin to hermetically seal the thin film EL element 2.
Constructs an envelope 10 that seals the. Reference numeral 11 denotes an insulating protective fluid such as silicone oil filled in the internal space of the envelope 10 in order to improve the moisture resistance of the thin film EL element 2. The fluid is injected through an injection hole 12 formed in a part of the cover glass 8. After injection, the injection hole 12 is sealed with a cover plate 13.

By the way, one end of each of the transparent electrode 3 and the back electrode 7 is extended to the peripheral part of the glass substrate 1, and each extended end is connected to a terminal part 14, 15 formed on the peripheral part of the glass substrate 1. is connected in a superimposed manner. The terminal portion 14 on the side of the transparent electrode 3 disposed along the X direction is formed to overlap the extending end portion of the transparent electrode 3, while the back electrode 7 disposed along the Y direction An extended end portion of the back electrode 7 is formed to overlap with the terminal portion 15 on the side. Reference numeral 16 denotes a flexible lead for externally extending the electrodes of the thin film EL element 2, which is made by adhering a large number of external leads 18 such as copper foil to a plastic film 17, and has a large number of terminal parts 1.16 exposed from the envelope 10. 4.
The corresponding ends of external leads 18 on 15 are electrically and mechanically connected with solder.

[Problem to be solved by the invention]

At the periphery of the conventional 1iEL element 2 described above, the back electrode 7 is bent due to the contraction force of the adhesive 9 that fixes the cover glass 8 to the glass substrate 1, the warpage of the cover glass 8, etc., as shown in FIG. There was a problem in that the thin film EL element 2 was cut off at the end, making it impossible to conduct electricity to the thin film EL element 2, and the reliability was also significantly reduced.

An object of the present invention is to provide a highly reliable thin film EL display panel in which the back electrode is not cut and electricity cannot be supplied to the thin film EL element.

[Means to solve the problem]

The present invention provides a thin-film EL display panel in which a thin-film EL element is enclosed in an envelope formed by bonding a glass substrate and a cover glass, in which a conductive terminal for taking out an external terminal of the thin-film EL element is embedded in the cover glass. It is characterized by

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIGS. 1(a) and (b) are cross-sectional views in the X and Y directions of the first embodiment of the present invention, respectively, and FIGS. 2(a) and (b) are respectively FIGS. FIG. 3B is a partially enlarged cross-sectional view of the external terminal extraction portion of FIG. Fig. 1 (a>, (b)) and Fig. 2 (a).

In (b), 21 is a transparent glass substrate;
2 is a matrix type thin film EL element formed on a glass substrate 21. 23 in this thin film EL element 22
24 is a transparent electrode on a stripe made of ITO formed at a predetermined pitch along the X direction by a vapor deposition method or a sputtering method; 24 is a transparent first dielectric layer such as Y2O3 that covers the transparent electrode 23; ZnS:Mn formed on the first insulating layer 24
26 is a transparent second dielectric layer such as Y2O5 that covers the light emitting layer 25, and 27 is a back surface made of a striped A1 vapor deposited film formed on the second dielectric layer 26 along the Y direction. It is an electrode. 28 is a cover glass, and adhesive 29
Therefore, the thin film EL element 22 is fixed to the glass substrate 21.
An envelope 30 is configured.

40 is a striped conductive terminal embedded in the cover glass 28 at a predetermined pitch; the conductive terminal 40, the transparent electrode 23, and the back electrode 27 have the same pitch. Transparent electrode 2
3 and one end of the back electrode 27 are extended to the front of the bonding portion of the cover glass 28 to the glass substrate 21, and these extended ends and the conductive terminal 40 embedded in the cover glass 28 are connected in an overlapping manner.

31 is an insulating protective fluid such as silicone oil filled in the inner space of the envelope 30 and is injected from an injection hole 32 formed in the cover glass, and after injection, the injection hole 32 is sealed with a cover plate 33. Reference numerals 34 and 35 indicate terminal portions that are overlapped and connected to draw out the conductive terminal 40. 36 is thin film EL element 2
This is a flexible lead for externally drawing out the electrodes of No. 2, in which a large number of external leads 38 such as copper foil are adhered to a plastic film 37 in a striped manner, and terminal portions 34 and 35 are formed on the periphery of the glass substrate 21. The ends of the external leads 38 corresponding to the top are electrically and mechanically connected with solder.

In this embodiment, the terminals of the thin-film EL element are drawn out of the envelope through the conductive terminals embedded in the cover glass, so there is no risk of failure in energization due to cutting of the extended part of the electrode for terminal extraction. Can be effectively prevented.

FIGS. 3(a) and 3(b) are partially enlarged cross-sectional views of the external terminal extraction portion in the X direction and the Y direction, respectively, of the second embodiment of the present invention. In the second embodiment, as shown in FIGS. 3(a) and 3(b), a cover glass is attached to an outer frame portion 2 including a conductive terminal 40.
8a and a lid portion 28b, first, the outer frame portion 28a is fixed to the glass substrate 21 with an adhesive 29, and then a conductive material 41 such as silver paste is applied to the conductive terminal 40 and the transparent electrode 23. The adhesive portion with the back electrode 27 is reinforced. After this, the lid part 28
b is fixed to the outer frame portion 28a with an adhesive 42 to form a cover glass.

As a result, the conductive terminal 40 and the transparent electrode 23. Back electrode 2
There is an advantage that the adhesion with 7 becomes stronger.

〔Effect of the invention〕

As explained above, the present invention allows the terminals of the thin IEL elements of the thin-film EL display panel to be drawn out of the envelope through the conductive terminals embedded in the cover glass, which is a problem that often occurs in conventional methods. This has the effect of eliminating failures in conduction due to cutting of the electrode extension portion for drawing out the terminals of the thin film EL element under the adhesive portion of the cover glass to the glass substrate.

[Brief explanation of drawings]

FIGS. 1(a) and (b) are cross-sectional views in the X and Y directions of the first embodiment of the present invention, respectively, and FIGS. 2(a) and (b) are respectively FIGS. FIGS. 3(a) and 3(b) are partially enlarged sectional views of the external terminal extracting portion in the X direction and Y direction of the second embodiment of the present invention, respectively; FIGS. 4(a) and 4(b) are cross-sectional views in the X direction and Y direction of an example of a conventional thin film EL display panel, respectively, and FIG. 5(a) is a cross-sectional view of an example of a conventional thin film EL display panel. (b) is a partially enlarged cross-sectional view of the external terminal take-out portion of FIGS. 4(a) and (b), respectively, and FIG. 6 is an enlarged cross-sectional view of a main part illustrating a state in which the extended portion of the back electrode is cut. 1.21...Glass substrate, 2,22...Thin EL element, 3,23...Transparent electrode, 4,24...First dielectric layer, 5,25...Light emitting layer , 6.26... Second dielectric layer, 7, 27... Back electrode, 8, 28... Cover glass, 9.29.42... Adhesive, 10.30
... Envelope, 11.31 ... Insulating protective fluid, 12
゜32... Injection hole, 13.33... Lid plate, 14.1
5゜34.35... Terminal part, 16.36... Flexible lead, 17.37... Plastic film, 18.38... External lead, 40... Conductive terminal,
41... Conductive material, 28a... Cover glass (outer frame part), 28b... Cover glass (lid part).

Claims (1)

[Claims] A thin film EL display panel in which a thin film EL element is enclosed in an envelope formed by bonding a glass substrate and a cover glass, characterized in that a conductive terminal for taking out an external terminal of the thin film EL element is embedded in the cover glass. Thin film EL display panel.