JP2006324261A - Organic electroluminescent display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL display device wherein thickness in depth can be made thin as much as possible, and to provide an organic EL display with excellent moisture resistance. <P>SOLUTION: This organic electroluminescent display device is provided with a first substrate wherein at least an organic luminous element layer is formed in one surface and a second substrate disposed facing the surface wherein the organic luminous element layer of the first substrate is formed. The first substrate and the second substrate are fixed through a wall. The second substrate has a spacer extended along a first side of the second substrate in a surface facing the organic luminous element layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic electroluminescence display device.

An organic electroluminescence display device (hereinafter referred to as an organic EL ((Electro Luminescence)) display device) is composed of an organic EL laminated body that emits light independently for each pixel on the back surface of the transparent substrate on the observation side. An organic light emitter layer is formed.
And the said transparent substrate comprises the envelope of this organic EL display apparatus with the sealing cap attached so that the said organic EL laminated body of the back surface might be enclosed.

  The sealing cap is easily affected by moisture present in the surroundings of the organic EL laminated body. Therefore, the sealing cap and the surrounding area of the organic EL laminated body together with the transparent substrate are used to improve moisture resistance. Yes.

However, the organic EL display device having such a configuration has a shape formed into a container shape because the sealing cap is combined with a flat transparent substrate to form the sealed space. there were.
For this reason, there has been a disadvantage that the depth of the organic EL display device becomes relatively large.

  In addition, it is usual to apply a desiccant-containing layer on the inner surface of the sealing cap to achieve a moisture resistance effect, but there has been a disadvantage that it is relatively difficult to form this desiccant-containing layer. .

The present invention has been made based on such circumstances, and an object thereof is to provide an organic EL display device capable of reducing the depth as much as possible.
Another object of the present invention is to provide an organic EL display device excellent in moisture resistance.

  Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.

Means 1.
An organic EL display device according to the present invention includes, for example, a transparent substrate having at least an organic light emitter layer formed on one surface thereof, and a flat plate disposed to face the surface of the transparent substrate on which the organic light emitter layer is formed. Shaped substrate and
The substrate is fixed to the transparent substrate through a wall.

Mean 2
The organic EL display device according to the present invention is characterized in that, for example, on the premise of the configuration of the means 1, a desiccant is disposed on the surface of the flat substrate facing the organic light emitting layer. is there.

Means 3.
The organic EL display device according to the present invention is characterized in that, for example, the configuration of the means 2 is premised, and the amount of the desiccant is larger in the vicinity of the wall than in other portions.

Means 4.
The organic EL display device according to the present invention is based on, for example, the configuration of the means 1, and the wall body has one formed on the transparent substrate side and one formed on the flat substrate side, and the positions thereof are It is characterized by being formed out of alignment.

Means 5.
An organic EL display device according to the present invention includes, for example, a transparent substrate having at least an organic light emitter layer formed on one surface thereof, and a flat plate disposed to face the surface of the transparent substrate on which the organic light emitter layer is formed. Shaped substrate and
The substrate is fixed to the transparent substrate through a wall body, and a spacer is disposed between the substrate surrounded by the wall body and the transparent substrate. is there.

Means 6.
The organic EL display device according to the present invention is characterized in that, for example, the configuration of the means 5 is premised, and the spacer is formed simultaneously with the formation of the wall body.
In addition, this invention is not limited to the above structure, A various change is possible in the range which does not deviate from the technical idea of this invention.

  As is apparent from the above description, according to the organic EL display device of the present invention, the depth thickness can be reduced as much as possible. Moreover, the thing excellent in moisture resistance can be obtained.

  Embodiments of an organic EL display device according to the present invention will be described below with reference to the drawings.

Example 1.
<Overall configuration>
FIG. 2 is an overall plan view showing an embodiment of the organic EL display device according to the present invention. Although the figure shows an equivalent circuit, it is drawn so as to substantially correspond to the actual geometric arrangement.
In the figure, there is a transparent substrate SUB1. The transparent substrate SUB1 is arranged on the viewer side, and the viewer observes the display through the transparent substrate SUB1.
On the back surface of the transparent substrate SUB1, gate signal lines GL extending in the x direction and arranged in parallel in the y direction and drain signal lines DL extending in the y direction and arranged in parallel in the x direction are formed. .
A region surrounded by each gate signal line GL and each drain signal line DL constitutes a pixel region, and a matrix-like aggregate of these pixel regions constitutes an image display unit AR.

Further, a common electrode signal line CL is formed in common for each pixel arranged in the x direction in the figure, and this common electrode signal line CL is connected in common with other common electrode signal lines CL.
In each pixel region, a thin film transistor TFT operated by a scanning signal from one side gate signal line GL and a pixel electrode PX to which a video signal from one side drain signal line DL is supplied via the thin film transistor TFT are formed. Has been.
The pixel electrode PX is configured to sandwich a light emitting material layer FLR made of organic EL with the counter electrode CT connected to the counter electrode signal line CL, and the light emitting material layer FLR emits light by a current flowing therethrough. It has become.

One end of each of the gate signal lines GL extends to the periphery of the transparent substrate SUB1, and the extended end constitutes a terminal to which the output terminal of the scanning signal driving circuit V is connected. A signal from a printed circuit board (not shown) disposed around the transparent substrate SUB1 is input to the input terminal of the scanning signal drive circuit V.
The scanning signal drive circuit V is composed of, for example, a plurality of semiconductor devices formed by a tape carrier method, and is grouped for each of a plurality of adjacent gate signal lines GL, and one semiconductor device is assigned to each of these groups. It is like that.

Similarly, one end of each of the drain signal lines DL extends to the periphery of the transparent substrate SUB1, and the extended end constitutes a terminal to which the output terminal of the video signal driving circuit He is connected. . The input terminal of the video signal driving circuit He receives a signal from a printed circuit board (not shown) arranged around the transparent substrate SUB1.
This video signal drive circuit He is also composed of a plurality of semiconductor devices formed by a tape carrier system, and is grouped for each of a plurality of drain signal lines DL adjacent to each other, and one semiconductor device is assigned to each of these groups. It is like that.

One of the gate signal lines GL is sequentially selected by a scanning signal from a scanning signal driving circuit V.
In addition, a video signal is supplied to each of the drain signal lines DL by the video signal driving circuit He in accordance with the selection timing of the gate signal line GL.

  Further, a sealing substrate SUB2 is disposed opposite to the surface of the transparent substrate SUB1 on which the gate signal line GL, the drain signal line DL, the thin film transistor TFT, etc. are formed so as to sufficiently cover the image display portion AR. The transparent substrate SUB1 is fixed by a sealing wall SW formed around the sealing substrate.

Here, like the transparent substrate SUB1, the sealing substrate SUB2 has a flat plate shape, and is made of, for example, stainless steel or a transparent substrate. In this case, the sealing substrate SUB2 is not particularly limited to the above-described material, and may be another material.
The space between the transparent substrate SUB1 and the sealing substrate SUB2 is filled with an inert gas such as nitrogen (N), for example, and a desiccant is applied to the surface of the sealing substrate SUB2 facing the transparent substrate SUB1. It has been applied.

  In the above-described embodiment, the scanning signal driving circuit V and the video signal driving circuit He are so-called tape carrier type semiconductor devices connected across the transparent substrate SUB1 and the printed circuit board. For example, it may be a chip-like semiconductor device mounted on the transparent substrate SUB1, and when the semiconductor layer of the thin film transistor TFT is composed of polycrystalline silicon (p-Si), the polycrystalline substrate is formed on the transparent substrate SUB1 surface. A semiconductor element made of silicon may be formed together with a wiring layer.

<Pixel configuration>
FIG. 3 is a plan view showing a configuration of one pixel formed on the surface of the transparent substrate SUB1, and is a view seen from the opposite side of the transparent substrate SUB1. FIG. 4 shows a cross-sectional view taken along line IV-IV in FIG.
In FIG. 3, first, a base layer GW made of SiO or SiN is formed on the surface of the transparent substrate SUB1. The underlayer GW is formed in order to avoid that ionic impurities contained in the transparent substrate SUB1 affect the thin film transistor TFT described later.
A semiconductor layer PS made of a polysilicon layer extending in the x direction is formed at, for example, the lower left portion of each pixel region of the base layer GW. The semiconductor layer PS becomes a semiconductor layer of the thin film transistor TFT.

An insulating film GI is formed on the surface of the substrate SUB, covering the semiconductor layer PS. This insulating film GI functions as a gate insulating film in the formation region of the thin film transistor TFT.
A gate signal line GL extending in the x direction and arranged in parallel in the y direction is formed on the surface of the insulating film GI. The gate signal line GL is formed so as to define the pixel region with a drain signal line DL described later.

In addition, the gate signal line GL is formed with an extension part extending so as to cross almost the central part of the semiconductor layer PS, and this extension part functions as the gate electrode GT of the thin film transistor TFT. It is supposed to be.
After the formation of the gate electrode GT, impurity ions are implanted using the gate electrode GT as a mask so that the resistance of the semiconductor layer PS in the region other than directly below the gate electrode GT is reduced.

An insulating film IN is formed on the surface of the substrate SUB, covering the gate signal line GL (gate electrode GT). This insulating film IN has a function as an interlayer insulating film for the gate signal line GL together with the insulating film GI in the drain signal line DL formation region described later.
A drain signal line DL extending in the y direction and arranged in parallel in the x direction is formed on the surface of the insulating film IN. A part of the drain signal line DL extends to one end of the semiconductor layer PS and is connected to the semiconductor layer PS through a through hole TH1 formed in advance through the insulating film IN and the insulating film GI. . That is, the extending portion of the drain signal line DL functions as the drain electrode SD1 of the thin film transistor TFT.

The other end of the semiconductor layer PS is formed with a source electrode SD2 that penetrates the insulating film IN and the insulating film GI and is connected through a previously formed through hole TH2. The source electrode SD2 is a pixel electrode that will be described later. An extension for connecting to PX is formed.
Then, the insulating film IL is formed on the surface of the substrate SUB on which the drain signal line DL (drain electrode SD1) and the source electrode SD2 are formed in this way, and the insulating film INL is further stacked on the upper surface thereof. Yes.

On the upper surface of the insulating film INL, a pixel electrode PX made of a light-transmitting conductive film such as ITO (Indium Tin Oxide) is formed in the center except for a slight periphery of each pixel region. The thin film transistor TFT is connected to the source electrode SD2 through a through hole TH3 formed in the insulating film INL and the insulating film IL.
A bank film BNK made of, for example, an organic material layer is formed on the surface of the transparent substrate SUB1 on which the pixel electrode PX is formed. A part of the bank film BNK film is perforated to remove the periphery of the pixel electrode PX. The part is exposed.

Further, a light emitting material layer FLR made of organic EL is formed on the surface of the bank film BNK and the pixel electrode PX exposed from the bank film BNK.
A counter electrode CT made of, for example, aluminum is formed over the entire surface of the light emitting material layer FLR. In this case, the aluminum functions as the counter electrode CT in a portion facing the pixel electrode PX through the light emitting material layer FLR, and the other portion functions as the counter electrode signal line CL shown in FIG.

  The present invention is not limited to the pixel configuration described above, and other configurations, that is, a configuration in which a layer called a hole injection layer, an electron injection layer, or an electron transport layer is added, or The present invention is also applicable to a configuration in which the bank layer BNK does not exist.

<Sealing wall body>
FIG. 1 is a view showing a cross section taken along the line II of FIG. In the figure, a sealing substrate SUB2 is disposed so as to face the surface of the transparent substrate SUB1 on which the gate signal line GL, the drain signal line DL, and the thin film transistor TFT are formed.
A sealing wall body SW is formed around the sealing substrate SUB2, and the sealing wall body SW is fixed to the transparent substrate SUB1 via an adhesive AD, whereby the image display portion AR of the transparent substrate SUB1 is formed. A sealed space is configured on the surface side of the.
This sealed space is filled with an inert gas such as nitrogen (N), for example, so as to chemically stabilize the light emitting material layer FLR.

The sealed space filled with the inert gas can be formed by assembling the sealing substrate SUB2 with the transparent substrate SUB1 in the inert gas.
When configured in this manner, the sealing substrate SUB2 can use a flat substrate similarly to the transparent substrate SUB1, so that the depth length W of the organic EL display device can be reduced.
A desiccant DR is formed on the surface of the sealing substrate SUB2 surrounded by the sealing wall body SW by, for example, coating. The desiccant DR is formed over almost the entire surface surrounded by the sealing wall SW, thereby increasing the drying efficiency in the sealed space.

Since the sealing substrate SUB2 is made of a flat substrate, it is possible to apply the desiccant DR over almost the entire surface of the sealing substrate SUB2 as an easy operation.
The desiccant DR is provided to prevent deterioration of the light emitting material layer FLR due to moisture.

  Further, on the outer wall surface of the sealing wall SW, for example, an epoxy resin EO is applied including a part of the upper and lower transparent substrates SUB1 and SUB2, and the transparent substrate SUB1 is applied by the epoxy resin EO. In addition, moisture is prevented from entering the sealed space in the sealing substrate SUB2.

Example 2
FIG. 5 is a block diagram showing another embodiment of the organic EL display device according to the present invention and corresponds to FIG.
A different configuration compared to FIG. 1 is the desiccant DR. That is, among the desiccant DR formed on the surface of the sealing substrate SUB2, in particular, the amount per unit area of the desiccant DR1 in the vicinity of the sealing wall body SW is the amount of the desiccant DR in the other region. That is, it is formed more than the amount per unit area.

In this embodiment, the area where the desiccant DR1 is formed has a multilayer structure, for example, so that the amount of desiccant DR in other areas is increased.
In view of the intrusion of moisture from the outside from the forming portion of the sealing wall body SW, it is intended to increase the moisture absorption capacity in the vicinity of the sealing wall body SW.
Since the inconvenience of deterioration due to moisture of the light emitting material layer FLR cannot be ignored as the size of the organic EL display device is increased, the above-described configuration is effective.

Example 3
FIG. 6 is a block diagram showing another embodiment of the organic EL display device according to the present invention and corresponds to FIG.
A different configuration compared to FIG. 1 is the sealing wall. That is, sealing wall bodies SW1 and SW2 are formed on the transparent substrate SUB1 and the sealing substrate SUB2, respectively, and the other sealing wall body is outside the one sealing wall body or the other sealing wall body. The position is shifted inside.
In this case, the moisture intrusion route becomes a labyrinth-like route, and the moisture prevention effect can be improved.

Further, as shown in FIG. 6, for example, the sealing wall body SW1 formed on the transparent substrate SUB1 is formed on the outer side and the inner side with respect to the sealing wall body SW2 formed on the sealing substrate SUB2. There is an effect that the sealing wall body can be formed with a constant width w.
The pair of sealing wall bodies SW1 formed on the transparent substrate SUB1 becomes a sealing wall of the adhesive AD filled between them, and can be prevented from getting over the sealing wall and entering the image display unit AR side. Because.
In addition, by using a photo-curable adhesive AD, as shown in FIG. 6, the adhesive AD can be easily cured by irradiation with UV light.

Example 4
FIG. 7 is a plan view showing another embodiment of the organic EL display device according to the present invention. For example, the spacers SP are scattered in the sealing wall of the sealing substrate SUB2.
In FIG. 7A, the shape of the spacer SP is round, and the spacers SP are arranged almost uniformly in the sealing wall SW.

  This spacer SP is for making the gap between the transparent substrate SUB1 and the sealing substrate SUB2 uniform, and when the organic EL display device is enlarged or at least one of the transparent substrate SUB1 and the sealing substrate SUB2. This is effective when the rigidity is not sufficient.

Since the spacer SP is formed at substantially the same height as the sealing wall body SW, it can be formed simultaneously with the formation of the sealing wall body SW, and in this case, an increase in the number of manufacturing steps can be avoided.
Of course, each of these spacers SP may be formed on the sealing substrate SUB2 via the desiccant DR, or may be formed in a selective removal portion of the desiccant DR.

  FIG. 7B shows a change in the shape of the spacer SP, and a rectangular spacer SP extending in the y direction and arranged in parallel in the x direction is provided. Similarly, it goes without saying that spacers SP extending in the x direction and arranged in parallel in the y direction may be provided.

Furthermore, in this embodiment, the spacer SP is formed on the sealing substrate SUB2 side, but it goes without saying that it may be formed on the transparent substrate SUB1 side.
Each of the embodiments described above may be used alone or in combination. This is because the effects of the respective embodiments can be achieved independently or synergistically.

It is a block diagram which shows one Example of the organic electroluminescence display by this invention, and is sectional drawing in the II line | wire of FIG. 1 is an overall configuration diagram showing an embodiment of an organic EL display device according to the present invention. It is a top view which shows one Example of the pixel of the organic electroluminescent display apparatus by this invention. It is sectional drawing in the IV-IV line of FIG. It is a block diagram which shows the other Example of the organic electroluminescent display apparatus by this invention. It is a block diagram which shows the other Example of the organic electroluminescent display apparatus by this invention. It is a top view which shows the other Example of the organic electroluminescent display apparatus by this invention.

Explanation of symbols

SUB1 ... Transparent substrate, SUB2 ... Sealing substrate, SW ... Sealing wall, AD ... Adhesive, DR ... Drying agent, GL ... Gate signal line, DL ... Drain signal line, TFT ... Thin film transistor, PX ... pixel electrode, CT ... counter electrode, FLR ... light emitting material layer.

Claims (5)

A first substrate having at least an organic light emitter layer formed on one surface;
A second substrate disposed opposite to a surface of the first substrate on which the organic light emitting layer is formed,
The first substrate and the second substrate are fixed to each other through a wall body,
The organic electroluminescence display device, wherein the second substrate has a spacer extending along a first side of the second substrate on a surface facing the organic light emitting layer. In claim 1,
The organic electroluminescence display device, wherein the spacer is provided on a second side adjacent to the first side. In claim 1 or 2,
An organic electroluminescence display device, wherein the spacer has a rectangular shape. In claims 1 to 3,
The organic electroluminescence display device, wherein the spacer has substantially the same height as the partition wall. A first substrate having at least an organic light emitter layer formed on one surface;
A second substrate disposed opposite to a surface of the first substrate on which the organic light emitting layer is formed,
On one surface of the first substrate, provided with a partition, and a wiring formed between the partition and the first substrate,
The partition and the second substrate are fixed via an adhesive,
An organic electroluminescence display device, wherein a sealing space is provided between the first substrate and the second substrate, and a desiccant is provided on a second substrate surface on the sealing space side.

Images