JP2002305076A - Display equipment and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress generating of a dark spot by moisture and occurring of exfoliation of a negative electrode in display equipment using an organic light emitting diode(OLED). SOLUTION: Making a peripheral edge part of a sealed substrate (a 2nd substrate) 102 have a convex-like structure, a gap between the sealed substrate and an element substrate is controlled by the convex-like part. Then, a layer 106, which has needed adhesive ability sticking the sealing substrate and the element substrate becomes unnecessary, and for this reason, the layer 16 can be made as thinly as possible. Thus, quantity of the moisture, which invades the sealing domain passing the layer, which consists of an organic material and has adhesive ability, can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using an organic light emitting device and a method for manufacturing the same, and more particularly, to a display device using an organic light emitting device that maintains stable light emitting characteristics for a long period of time.

[0002] In this specification, an organic light-emitting element is an element which emits light with an organic compound interposed between two electrodes. Organic light emitting devices include organic light emitting diodes (Organi
c Light emitting devices using Light Emitting Diode (OLED). An organic light-emitting diode is a device in which an organic compound is sandwiched between two electrodes, holes are injected from one electrode, and electrons are injected from the other electrode, so that electrons and electrons are injected into the organic compound layer. A luminous body that emits light when combined with a hole.

[0003]

2. Description of the Related Art In recent years, display devices using organic light emitting elements have been actively studied. A display device using an organic light emitting element can be lighter and thinner than a conventional CRT.
Applications to various applications are underway. Mobile phones and personal digital assistants (Personal Digital Assistant: PD
A), etc., can be connected to the Internet, and the amount of information shown on the video display has increased dramatically, and the demand for color and high definition display devices has increased.

On the other hand, the weight of the display device mounted on such a portable information terminal is emphasized. For example, a mobile phone weighing less than 70 g is on the market. In order to reduce the weight, most of the components used, such as individual electronic components, housings, and batteries, are being reviewed. However, in order to further reduce the weight, it is necessary to promote the reduction in the weight of the display device.

A display device having a pixel portion formed of an organic light emitting element is a self-luminous type and does not require a light source such as a backlight unlike a liquid crystal display device. Therefore, it is promising as a means for achieving weight reduction and thinning. Have been.

[0006]

The organic light-emitting element can emit blue light, and can realize a full-color display self-luminous display device. However, various deterioration phenomena have been confirmed in the organic light emitting device, and the solution is urgently required as a problem that hinders practical use.

[0007] For example, a dark spot is a non-light emitting point defect appearing in a pixel portion, and has been regarded as a problem as significantly reducing display quality. It is said that the dark spot is a progressive defect and increases when moisture is present without operating the device. It is considered that the cause of the dark spot is an oxidation reaction of a cathode formed using an alkali metal.

Therefore, in a display device using an organic light-emitting element, an element substrate provided with a light-emitting element and a sealing substrate provided opposite to the element substrate are bonded to each other with an adhesive sealing material. The light emitting element is not exposed to the outside air containing moisture. The sealing substrate is made of a metal such as stainless steel or aluminum which is easy to process,
A desiccant is arranged in a depression on the surface of the sealing substrate.

A filler is mixed in the sealing material to control a gap between the element substrate and the sealing substrate. For this reason,
The sealant has both a function of bonding the sealing substrate and the element substrate and a function of controlling a gap between the sealing substrate and the element substrate. For this reason, when the gap between the element substrate and the sealing substrate is set to a general value of 10 μm to 50 μm, the thickness of the sealing material has to be changed accordingly.

[0010] The shortest distance between the light emitting element and the surface of the sealing substrate facing the light emitting element is referred to as a gap between the sealing substrate and the element substrate, or simply a gap.

Incidentally, the sealing material for controlling the gap between the element substrate and the sealing substrate is made of an organic resin material, and has a higher moisture permeability than an inorganic material such as a glass material. For example, at 60 ° C. and 90% humidity, the moisture permeability is 15 g / m ² · 24 hr to 30
g / m ² · 24 hr. Even when the sealing substrate and the element substrate are sealed with a sealant, the organic light-emitting element is deteriorated by water vapor passing through the sealant and entering the sealing region.
The amount of water vapor passing through the sealing material is determined by the product of the area of the sealing material exposed to the outside air and the moisture permeability. For this reason, it is desirable that the area of the sealing material exposed to the outside air be small. That is, it is desirable that the sealing material be as thin as possible.

That is, as the thickness of the sealing material increases,
The amount of moisture passing through the sealant increases, and even if a desiccant is provided, the light emitting element is deteriorated by moisture that cannot be absorbed by the desiccant. Therefore, it is an object of the present invention to reduce the amount of moisture passing through the sealing material.

[0013] To reduce the weight of a portable information terminal,
A method of reducing the thickness of the glass substrate can be considered. However, as the glass substrate becomes thinner, the glass substrate is liable to break and the impact resistance is reduced. In particular, when the sealing substrate made of metal and the element substrate made of glass are bonded together,
Due to a difference in thermal expansion coefficient, a strain is generated by a rapid temperature change, and a crack is generated in the glass substrate. However, this would be a fatal drawback for use in portable information terminals.

Therefore, it is an object of the present invention to prevent the substrate from being damaged and to increase the durability in a structure in which the glass substrate is made thinner and the display device is made thinner.

As described above, the display device including the organic light emitting element is very useful for reducing the weight of the display device.
There remains a problem to be solved in order to ensure the reliability of the organic light emitting device. The present invention is a technique for solving such a problem, and an object of the present invention is to provide a display device using an organic light emitting element with high reliability and a method for manufacturing the display device.

[0016]

According to the thinning of a glass substrate, when an element substrate made of glass and a sealing substrate made of metal are combined, a rapid temperature change occurs due to a difference in thermal expansion coefficient. The possibility that the element substrate made of glass is damaged is increased. To prevent this,
In the present invention, a substrate made of glass is applied to an element substrate and a sealing substrate, and the thermal expansion coefficients are made equal. This allows
The object of the present invention is solved by increasing the resistance to a rapid temperature change.

Further, according to the present invention, the surface of the sealing substrate made of glass is processed to form a depression, and a desiccant is placed in the depression. Thereby, a desiccant is provided in the gap sealed with the element substrate, the sealing substrate, and the sealing material as in the related art,
Moisture entering through the adhesive can be captured. As the desiccant, calcium oxide, barium oxide, or the like can be suitably used. The place where the desiccant is installed may be provided, for example, on a drive circuit. Then, in the sealing region between the element substrate and the sealing substrate, the desiccant is present in proximity to the light emitting element, so that penetration of moisture into the light emitting element can be reduced. Thereby, the stability of the light emitting element can be improved. For example, dark spots generated by oxidization of the cathode can be reduced.

Further, according to the present invention, a sealing substrate made of glass is processed, and an outer edge portion of the sealing substrate is projected into a convex shape.
The projection controls the gap between the element substrate and the sealing substrate. For this reason, the adhesive layer provided between the element substrate and the sealing substrate only needs to have a function of bonding the element substrate and the sealing substrate, and does not need a function of controlling the gap. For this reason, the layer having adhesiveness can be made as thin as possible as far as the material allows. Accordingly, the amount of moisture that passes through the adhesive layer and penetrates into the sealing region can be reduced, and the problem of the present invention of reducing the amount of moisture that passes through the adhesive layer is solved. Is done. The thickness of the layer having an adhesive property (adhesive) is preferably 10 μm or less, more preferably 1 μm or less.

As a method of processing the surface of the sealing substrate,
An abrasive processing method (sand blast method) can be used. The abrasive processing method is a technique of blowing sand or fine steel pieces together with compressed air to process the surface of a glass substrate.

An example of the structure of the present invention is shown in FIGS.
This will be described with reference to FIG. 8 (A) to 8 (C)
1 shows a cross-sectional view of a display device using the organic light emitting device of the present invention.

FIG. 8A shows a display device in which an element substrate and a sealing substrate are bonded together with an adhesive layer by processing the surface of the sealing substrate to form a desiccant and a moisture-permeable film. Are shown in the sealing region. First substrate 10
Each of the first and second substrates 102 is a light-transmitting substrate, for example, a glass substrate. The first substrate is an element substrate,
An organic light emitting element is provided in the display area 129. Second
Is a sealing substrate, the surface of which is processed and depressed, on which a desiccant 107 and a moisture-permeable film are provided. When light emitted from the organic light-emitting element is extracted from the side of the sealing substrate, the area where the desiccant and the moisture-permeable film are provided is desirably outside the display area.

In the present invention, the layer 1 having an adhesive property is used.
A region where 06 is on the same plane as a portion to be bonded to the second substrate is referred to as a first region 103 of the second substrate. A region that is concave with respect to the first region is referred to as a second region 104. A region that is concave with respect to the second region is referred to as a third region 105. That is, when the surface on the side facing the organic light emitting element is the surface of the front surface of the second substrate, when viewed from the back surface of the second substrate, the first region is different from the second region and the third region. It is protruding in a convex shape.

A desiccant 107 is provided in the third area 105. The desiccant can be a granular material,
A plate-like material can also be used. To fill the desiccant, the third region is 50-150 relative to the second region.
Preferably it has a depth of μm.

The moisture permeable film having high moisture permeability and water vapor permeability is composed of an adhesive layer 125, a porous layer 126 and a substrate 127. In order to confine the desiccant in the third area, an adhesive layer 125 is in contact with a part of the second area, and a moisture-permeable film is stretched. The moisture-permeable film composed of the adhesive layer, the porous layer, and the substrate has a thickness of 150 to 300 μm. Further, it is preferable that the first substrate is provided at a distance of 10 to 50 μm or more from the surface of the base material constituting the moisture permeable film so that the moisture permeable film does not contact the first substrate. For this reason, it is preferable that the second region is depressed by 160 to 350 μm with respect to the first region.

As the layer 106 having an adhesive property for adhering the element substrate and the sealing substrate, it is possible to use an ultraviolet curable resin or a thermosetting resin. The amount of water entering the sealing region is determined by the product of the area of the adhesive layer exposed to the outside air and the moisture permeability of the adhesive layer. For this reason, it is desirable that the layer having adhesiveness be as thin as possible to reduce the area that is exposed to the outside air.

According to the present invention, since the outer edge (first region) of the second substrate protrudes in a convex shape, the first edge of the second substrate has a height equal to the height of the convex portion of the outer edge. The gap between the first substrate and the second substrate can be determined. The adhesive layer does not require a function of controlling a gap, and may be used as an auxiliary to bond the second substrate to the first substrate. For this reason, the layer having adhesiveness can be made as thin as the material allows.

Next, another example of the present invention will be described. The present invention described below has a configuration that takes into account not only reducing the amount of moisture that penetrates through the layer having adhesiveness, but also reducing the amount of moisture remaining in the dry gas in the sealed region. It is.

FIG. 8B shows a cross section of the organic light emitting device. 8A is different from FIG. 8A in that the gap between the first substrate and the second substrate in the display region 129 is reduced to 10 to 50 μm. The moisture-permeable film is as thick as 150 to 300 μm, and a gap so thick is unnecessary in a display area where no moisture-permeable film is provided. The gap is reduced to 3% to 50% in the display region occupying the dominant area in the display device as compared with FIG. 8A (150 to 300 μm).
Is reduced to 10 to 50 μm), which contributes to reducing the volume of the sealing space, that is, the volume of the dry gas, and reduces the total amount of moisture remaining in the gas.

FIG. 8C shows an example in which a flat desiccant 107 is provided in the third region 105 of the second substrate 102. Calcium oxide or the like may be used as the flat desiccant.

In order to prevent the desiccant from being lost due to the impact and the fine powder from being mixed into the display area, an adhesive 109 is provided at several places on the surface of the desiccant to form a porous film 108 having a thickness of 10 to 30 μm. Affix to the desiccant using adhesive 109. In this manner, by covering the periphery of the desiccant with the porous film, fine powder generated due to the mechanical impact can be confined inside the porous film. It is preferable that the desiccant is exposed by exposing the porous film to two or three places in a circular shape, the adhesive 110 is applied to the exposed part, and the desiccant and the second substrate are bonded. By adjusting the amount of the adhesive applied to the surface of the desiccant, the thickness can be 1 to 5 μm. In FIG. 8C, 50 is set for the second area.
It is preferable to adjust the thickness of the porous film, the thickness of the desiccant, and the thickness of the adhesive so that the desiccant or the porous film enters the third region recessed to 150 μm.

In FIG. 8A and FIG. 8B, the moisture-permeable film has a thickness of 10 so as not to be crushed by the weight of the desiccant.
A substrate 127 having a thickness of 100 μm to 150 μm is provided in contact with a porous film 126 having a thickness of about 70 μm,
It was necessary to increase the mechanical strength by increasing the thickness of the multi-hard film. Furthermore, since the adhesive layer 125 having a thickness of 40 to 80 μm is required to adhere the film to the substrate, the thickness of the moisture-permeable film is 150 to 300 μm. Therefore, the amount of water remaining in the gas in the sealed space is increased by the volume occupied by the moisture-permeable film.

However, according to FIG. 8 (C), the film only needs to cover the periphery of the desiccant, and does not require a very high strength. Therefore, there is no practical problem even if a porous film as thin as 10 to 30 μm is used. In addition, as the film becomes thinner, the volume of the sealed space can be reduced. In order to enclose the desiccant, a porous film is provided on the upper surface (the surface facing the second substrate) and the lower surface (the surface facing the first substrate) of the desiccant.
When a porous film of 0 to 30 μm is used, the thickness occupied by the porous film between the gaps is twice that of 20 to 30 μm.
60 μm. Nevertheless, the thickness occupied between the gaps of the porous film can be made smaller than the thickness occupied by the moisture permeable film. If the amount of the desiccant is the same, FIG.
With this structure, the volume of the sealing region can be reduced, and the amount of moisture remaining in the gas decreases. this is,
This leads to suppression of the oxidation reaction of the cathode caused by moisture, and the useful life of the display device can be increased.

In FIG. 8C, the second region 104 is depressed by 10 to 50 μm with respect to the first region, and the gap between the first substrate and the second substrate in the display region is reduced by one.
It is preferable to set it to 0 to 50 μm.

In the present invention, since the sealing substrate and the element substrate are translucent, the emission direction of the emitted light of the organic light emitting element provided on the element substrate is the same as that of the element substrate even on the sealing substrate side. The side is fine. It is possible to freely design in consideration of the light emitting area and the like of the organic light emitting element.

The present invention based on the above description is as follows.

The invention (1) described in the present specification has a first substrate provided with an organic light-emitting element, and a second substrate having a light-transmitting property. The second substrate is bonded using an adhesive layer, and the second substrate is bonded to the second substrate.
The surface of the substrate facing the first substrate has a first region and a second region, the first region is bonded with the adhesive layer, and the second region is the second region. A display device, which is located inside a first region and is concave with respect to the first region.

In the invention (1) described in the present specification, it is sufficient that the portion of the sealing substrate on which the adhesive layer is provided is convex with respect to the element substrate. Thereby, the first substrate and the second substrate
The gap between the first substrate and the second substrate can be determined by the convex portion of the second substrate.
It can be used only for the purpose of bonding with the substrate.

The invention (2) described in the present specification has a first substrate provided with an organic light emitting element, and a second substrate having a light-transmitting property. The second substrate is bonded using an adhesive layer, and the second substrate is bonded to the second substrate.
The surface of the substrate facing the first substrate has a first region, a second region, and a third region, and the first region is bonded with the adhesive layer, The second region is inside the first region and is concave with respect to the first region, and the third region is inside the second region and is concave with respect to the second region. And a desiccant is provided in the third region.

In the invention (2) described in this specification, the sealing substrate has a function of controlling the gap since the second substrate has a convex shape with respect to the portion to which the adhesive layer is adhered. This is the same as the invention (1) described in this specification. further,
A desiccant is provided in the depression on the surface of the second substrate to capture moisture penetrating into the sealing region, thereby ensuring the stability of the organic light-emitting element in long-term operation.

According to the invention (3) described in the present specification, in the invention (2) described in the present specification, a moisture-permeable film adheres to a part of the second region, and the desiccant is added to the second region. 3 is a display device that is provided so as to be confined in the region of No. 3.

As in the invention (3) described in the present specification, a moisture-permeable film may be used as a means for installing a desiccant in the third region.

According to the invention (4) described in the present specification, the first substrate provided with the organic light-emitting element and the periphery of the region provided with the organic light-emitting element on the first substrate are separated by a gap. An enclosing adhesive layer and a light-transmitting second substrate, wherein the first substrate and the second substrate are attached to each other using the adhesive layer; A surface of the second substrate facing the first substrate has a first region and a second region.
And a third region, wherein the first region is bonded with the adhesive layer, and the second region is the first region.
And the third region is between the layer having the adhesive property and the region above the organic light emitting element, and the third region is located between the first region and the second region. The display device is concave with respect to the region, and a desiccant is provided in the third region.

The invention (4) described in the present specification is different from the invention (2) described in the present specification in that the region where the desiccant is provided is limited outside the display region.

The invention (5) according to the present invention is the invention (4) according to the invention (4), in which the moisture-permeable layer is provided between the adhesive layer and the region above the organic light-emitting element. Wherein the moisture-permeable film is adhered to a part of the second region, and the desiccant is confined in the third region.

As in the invention (5) described in the present specification, a moisture-permeable film may be used as a means for installing a desiccant in the third region. The moisture-permeable film is preferably disposed outside the display area.

The invention (6) described in the present specification is the invention (3) or the invention (5) described in the present specification, wherein the moisture-permeable material adhered to the second region is used. The display device is characterized in that the film fits between a plane contacting the first region and a surface where the moisture-permeable film adheres to the second region. That is, it is necessary at least that the moisture-permeable film does not contact the first substrate.

The invention (7) described in the present specification is the invention (2) described in the present specification or the invention (4) described in the present specification, wherein the second region is concave with respect to the first region. The difference between the height of the bottom of the region and the height of the first region is 10 μm to 5 μm.
A display device having a thickness of 0 μm or less. An example of the invention (7) described in this specification has already been described with reference to FIG.

The invention (8) described in the present specification is the invention (3) or the invention (5) described in the present specification, wherein the first region is concave with respect to the first region. A height difference between the bottom of the second region and the first region is not less than 160 μm and not more than 350 μm. One example of the present invention described in claim 8 has already been described with reference to FIGS. 8A and 8B.

The invention (9) described in the present specification is the invention according to any one of the inventions (1) to (8) described in the present specification, wherein the third region is concave with respect to the second region. The difference between the bottom of the region and the height of the second region is 50 μm or more and 150 μm or more.
It is a display device characterized by being not more than μm. One example of the present invention described in the invention (9) described in this specification is shown in FIG.
This has already been described with reference to FIGS.

According to the invention described in the invention (10) described in this specification, the invention described in any one of the inventions (1) to (9) described in the specification is characterized in that the first substrate or the second substrate The substrate is a glass substrate.

As the thickness of the substrate is reduced, the impact resistance is reduced. Therefore, if the material of the substrate is different, a rapid change in temperature may cause a crack in the substrate made of glass. This is a phenomenon caused by a difference in thermal expansion coefficient. However, if the first substrate and the second substrate are made of the same material, generation of cracks due to thermal shock can be prevented.

The invention (11) described in the present specification is the invention according to any one of the inventions (1) to (10) described in the present specification, wherein the second substrate is provided with irregularities, The distance between the protrusion and the tip of the protrusion adjacent to the protrusion is 0.05 to 1
A display device having a range of μm.

The second substrate is provided with projections and depressions, and light incident from the outside is reflected in all directions by the projections and depressions on the surface of the second substrate, so that reflection on the second substrate is prevented. it can.

The invention (12) described in the present specification is the invention according to any one of the inventions (1) to (11) described in the present specification, wherein the thickness of the adhesive layer is 10 μm or less. A display device characterized in that:

In the present invention, since it is not necessary to maintain the gap by the adhesive layer, the thickness of the adhesive layer can be reduced as much as possible. In particular, it is desirable that the thickness of the layer having adhesiveness be 10 μm or less in order to suppress the penetration of moisture into the sealing region.

According to the invention (13) described in this specification, a first substrate having a light-transmitting property and a second substrate are attached to each other using a layer having an adhesive property, and an organic layer is provided on the first substrate. In a method for manufacturing a display device provided with a light-emitting element,
A region of the second substrate to which the layer having the adhesive property is adhered is defined as a first region, and at least a first region is formed in the first region.
A first step of providing a mask, and a second step of excavating the second substrate by an abrasive processing method to form a second region that is concave with respect to the first region; A third step of removing the first mask, and a second mask formed on at least a region of the second substrate provided with the first mask and a region above the region provided with the organic light emitting element. A fourth step of excavating the second substrate by a sand processing method to form a third region that is concave with respect to the second region, and applying a desiccant to the third region. And a fifth step of providing a display device.

The invention (14) according to the present invention is the invention (13) according to the invention (13), wherein a moisture-permeable film is provided in the second region after the fifth step. A method for manufacturing a display device, which includes a step.

As a method of installing the desiccant in the third area, a method of adhering the desiccant to the second substrate and a method of adhering the adhesive layer of the moisture-permeable film to the second area to apply the desiccant to the third area are used.
The invention (14) described in the present specification is a method used to adopt the latter method.

According to the invention (15) described in the present specification, in the invention (14) described in the present specification, the excavation depth of the second substrate in the second step is the same as that of the moisture-permeable film. This is a method for manufacturing a display device, characterized in that the display device is deeper than the thickness of the display device.

The invention (16) described in the present specification is characterized in that, in the invention (13) described in the present specification, the excavation depth in the second step is 10 μm or more and 50 μm or less. This is a method for manufacturing a display device. According to the invention described in the invention (16) described in this specification, for example, by processing the surface of the second substrate in the configuration of FIG. 10 areas
It can be recessed to at least 50 μm.

The invention described in the invention (17) described in the present specification is the invention (14) described in the specification or the invention (15) described in the present specification, wherein the second step is performed in the second step. A method for manufacturing a display device, wherein a depth of excavation is not less than 160 μm and not more than 350 μm. According to the invention (17) described in this specification, in the structure of FIG. 8A or 8B, the second region 104 is recessed from the first region 103 to 160 μm or more and 350 μm or less. be able to.

The invention (18) described in the present specification is the invention according to any one of the inventions (13) to (17) described in the present specification, wherein the depth of the excavation is 50 in the third step.
A method for manufacturing a display device, which is not less than μm and not more than 150 μm. According to the invention (18) described in this specification, as shown in FIGS. 8A to 8C, the third region 105 where the desiccant is provided is 50 μm with respect to the second region 104.
m and 150 μm or less.

The invention (19) described in the present specification is the invention according to the inventions (13) to (16) described in the present specification, wherein the first substrate and the second substrate are provided after the fifth step. And a sixth step of bonding using the layer having the adhesive property,
And a seventh step of cutting the first substrate and the second substrate using a gas laser.

According to the invention (20) described in the present specification, in any one of the inventions (14) to (16) described in the present specification, after the sixth step, the first substrate A seventh step of bonding the second substrate with the layer having the adhesive property, and an eighth step of cutting the first substrate and the second substrate using a gas laser. A method for manufacturing a display device, characterized in that:

According to the invention described in the invention (21) described in this specification, the gas laser according to the invention (19) described in this specification or the invention (20) described in this specification is CO 2
This is a method for manufacturing a display device, which is characterized by using _two lasers.

[0066]

[Embodiment 1] An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view of an active matrix type display device using an organic light emitting element.

On the first substrate (element substrate) 101, T
The driving circuit portion 111 and the pixel portion 112 are formed using FT.

First substrate and second substrate (sealing substrate) 1
For 02, a substrate made of glass such as barium borosilicate glass, aluminoborosilicate glass, or quartz glass is used.

The surface of the second substrate is processed by an abrasive processing method and is selectively shaved. Through this processing, the surface of the second substrate has a first region 103, a second region 104, and a third region 105. The first region is a surface to which an adhesive layer is bonded. With reference to the back surface of the second substrate, the first region protrudes in a convex shape as compared with the second region and the third region.

For the layer 106 having adhesiveness, an epoxy-based adhesive is used. It is desirable that the adhesive layer be as thin as possible. The adhesive is L sold by Chisso
IXSON BOND LX-0001 can also be used. LX-0001 is a two-part epoxy resin. After applying LX-0001 to the first substrate, the substrate is cured at 100 ° C. for 2 hours while applying pressure around the first substrate and the second substrate. The adhesive after curing is 0.5 μm to 2.0 μm
Of thickness.

A desiccant 107 is provided in the depression in the third region. The desiccant uses calcium oxide. Known materials can be used as the desiccant. In this embodiment, a desiccant is used in the form of a flat plate. The thickness of the desiccant is 10 μm to 8
Desirably, it is 0 μm. In the present embodiment, the thickness of the desiccant is 80 μm. In particular, the desiccant absorbs moisture that enters the organic light-emitting element after the first substrate and the second substrate are sealed with an adhesive layer. Since the desiccant is provided close to the region where the light-emitting element is provided, the moisture concentration in the sealing region can be reduced and the life of the display device can be prolonged.

A porous film 108 is provided so as to cover the desiccant so that the fine powder of the desiccant does not move to the pixel portion and the drive circuit portion. The adhesive 109 is applied to the surface of the desiccant in a dot-like manner, and a porous film is attached to the desiccant. In addition, a porous film is cut out in a circular shape, an adhesive 110 is applied to a portion where the desiccant is exposed, and the desiccant 107 and the second
Is bonded to the substrate 102.

It is desirable that the thickness of the porous film be as thin as possible. In this embodiment, the thickness of the porous film is 10 μm. The amount of the adhesive can be adjusted to 5 μm or less, preferably 1 μm or less by adjusting the amount of the adhesive applied to the desiccant. In the present embodiment, the thickness of the adhesive is 5.0 μm. Since the thickness of the desiccant is 80 μm, if the third region is formed to be 110 μm concave with respect to the second region, the desiccant 107 and the adhesives 109 to 11 are formed in the third region.
0, a porous film 108 can be accommodated.

It is preferable that the gap between the first substrate and the second substrate in the pixel portion is set to 10 μm to 50 μm. In order to keep the gap of the pixel part in this range,
The second area 104 is set to 10 to 5 with respect to the first area 103.
It is good to make it concave about 0 μm. In the present embodiment, the gap between the first substrate and the second substrate in the pixel portion is 50 μm.
m, the second area is 48
μm concave. This is a value in consideration of the thickness (2 μm) of the adhesive layer in the present embodiment. In addition,
The gap between the organic light emitting element in the pixel portion and the sealing substrate has a strict difference of several μm depending on the thickness of the interlayer insulating film 121, but for convenience of explanation, the thickness of the interlayer insulating film is assumed to be negligible.

Since there is a gap of approximately 50 μm between the porous film 108 and the driving circuit, the porous film is in contact with the driving circuit 108 and it is possible to prevent the TFT of the driving circuit from being destroyed. .

The organic light emitting device 116 has a structure in which a cathode 113, an organic compound layer 114, and an anode 115 are laminated in this order, and light emitted from the light emitting device is emitted toward the second substrate 102. With such a structure, a cathode made of a reflective conductive film can be provided over the electrodes and wirings of the TFT, so that a light-emitting area is increased, and a display with high luminance and high visibility is obtained. .

As the cathode 113, a material containing magnesium (Mg), lithium (Li) or calcium (Ca) having a small work function is used. Preferably MgAg
(Material in which Mg and Ag are mixed at Mg: Ag = 10: 1)
May be used. In addition, MgAgAl electrode,
A LiAl electrode and a LiFAl electrode are mentioned. The cathode is formed using a material such as MgAg or LiF.
The thickness of the cathode may be 100 nm to 200 nm.

As the anode 115, an ITO (Indium Tin Oxide: Indium Tin Oxide) film which is a light-transmitting conductive film is formed. The thickness of the anode may be 100 nm to 200 nm.

The organic compound layer 114 is laminated in the order of electron transport layer / light emitting layer / hole transport layer / hole injection layer. A structure such as a transport layer / a light emitting layer / a hole transport layer / a hole injection layer may be employed. In the present invention, any known structure may be used.

As a specific light emitting layer, cyanopolyphenylene is used for the light emitting layer emitting red light, polyphenylene vinylene is used for the light emitting layer emitting green light, and polyphenylene vinylene or polyalkylphenylene is used for the light emitting layer emitting blue light. good. The thickness of the light emitting layer is 30 to 150 nm
It is good.

The above example is an example of a material that can be used for the light emitting layer, and is not limited to this.
Materials for forming the light emitting layer, the hole transport layer, the hole injection layer, the electron transport layer, and the electron injection layer can be freely selected in a possible combination thereof.

The TFTs of the drive circuit portion and the pixel portion are provided on the insulating base film 117. The TFT includes a semiconductor film 118, a gate insulating film 118, a gate electrode 119, an interlayer insulating film 121, a drain electrode 122, and a source electrode 12.
Consists of three. The thickness of the semiconductor layer is 10 to 150 nm, the thickness of the gate insulating film is 50 to 200 nm, the thickness of the gate electrode is 50 to 800 nm, the thickness of the interlayer insulating film is 1 to 6 μm,
The thickness of the drain electrode and the source electrode is 200 nm to 80
It is good to be 0 nm.

In order to prevent a short circuit between the anode 115 and the cathode 113 due to disconnection of the organic compound layer 114 or disconnection of the organic light emitting element, an organic material such as acryl or polyimide may be partially overlapped with the end of the cathode. A bank 124 made of a resin, preferably a photosensitive organic resin is provided. Bank 124
By forming the organic compound layer along the gentle taper, disconnection of the organic compound layer at the end of the cathode is prevented, and short-circuit between the anode and the cathode due to disconnection of the organic compound layer is prevented. The thickness of the bank is set to 1 to 3 μm.

In the present embodiment, the thickness of the layer having an adhesive property necessary for setting the gap between the first substrate and the second substrate in the pixel portion to 50 μm may be 2 μm. Therefore, the area of the side surface of the display device where the organic resin material is exposed to the outside air is reduced, and the amount of moisture passing through the organic resin material (the layer having adhesiveness) can be significantly reduced as compared with the conventional case. .

That is, it is possible to reduce the amount of water that penetrates the sealing space through the layer having adhesiveness, so that the object of the present invention can be solved and the life of the organic light emitting element can be increased.

FIG. 7 is a cross-sectional view for explaining a step of processing a substrate by a grinding sand processing method. As an example of an apparatus used for processing, MB-1 manufactured by Shinto Breiter Co., Ltd. can be mentioned.

FIG. 7A is a cross-sectional view in which a first mask 201 is disposed at a selective position on a substrate 202 made of glass before processing. The first mask is provided in a region where an adhesive layer is provided. The first mask is formed by attaching a film to the surface of a substrate, exposing the film to ultraviolet light, developing with a weak alkaline solution, and drying. It is desirable to use a UV-curable urethane resin for the film to be attached to the surface of the substrate. This is because the resistance is high in the step of grinding sand processing. The thickness of the first mask is 0.05 mm
It is good to be 0.5 mm.

FIG. 7B is a cross-sectional view showing a first processing step in which fine powder is sprayed onto a substrate by grinding sand processing to perform grinding sand processing. A fine powder having an average particle diameter of 3 μm to 40 μm is sprayed on the surface of the substrate, and a portion without the first mask is selectively removed. After processing, the substrate is washed to remove processing dust from the substrate. Thereby, the first region 20 is formed on the surface of the substrate.
3 and a second region 204 recessed with respect to the first region.

FIG. 7C is a cross-sectional view showing a second processing step in which the second mask 206 is provided on the substrate to perform grinding sand processing. By injecting fine powder and excavating the surface of the substrate, the third region 205 recessed with respect to the second region is formed on the surface of the substrate.
Can be.

FIG. 7D shows a cross section of the substrate after removing the second mask. In the present embodiment, the excavation depth in the first processing step is 48 μm, and the excavation depth in the second processing step is 110 μm. Assuming that the thickness of the substrate before processing is 0.6 mm, the thickness of the substrate in the first region 203 is 0.6 mm, and the thickness of the substrate in the second region 204 is 0.55.
2 mm, the thickness of the substrate in the third region 205 is 0.442 m
m. In the present embodiment, the second region occupies a large area. 0.55 thickness of substrate in second region
2 mm is a preferable value in terms of reducing the weight and thickness of the display device. Of course, the thickness of the second substrate before processing is 0.6
mm or less, it is possible to further reduce the weight of the display device.

Next, the amount of moisture that can be captured will be estimated from the amount of desiccant provided in the third region. The moisture permeability of the organic resin is 15 to 30 in an environment of 60 ° C. and 90% humidity.
g / m ² · day. In the present embodiment, the moisture permeability of the adhesive is set to 20 g / m ² · day, and the amount of moisture that passes through the adhesive and enters the sealing region is estimated.

The display device of this embodiment has a square outer shape with a side of 7 cm, and the height of an adhesive layer (adhesive) is 2 μm. The area where the adhesive layer is exposed to air is 0.56 × 10 ⁻⁶ m ² , and when the exposed area is multiplied by the moisture permeability, the amount of water permeated per day is 114 ×
It is 10 ^-7 g / day.

The amount of water for 10 years passing through the adhesive layer is 41.6 × 10 ⁻³ g. When calcium oxide is used as a desiccant, the amount of calcium oxide required to adsorb 1 g of water is 3 g, and the amount of calcium oxide capable of completely adsorbing water for 10 years is 125 mg. Since the specific gravity of the calcium oxide is 3.0 g / cm ³ , if the volume filled with the calcium oxide is 41.7 mm ^3, it is possible to completely adsorb moisture for 10 years that has penetrated from the adhesive layer.

The display area is a square having a side of 60 mm.
The width of the drive circuit unit is set to 60 mm parallel to the display area and 3 mm perpendicular to the display area. When three drive circuit units are provided (two gate drivers and one source driver), the area occupied by the drive circuit units is 540 mm ² . That is,
A gap is provided at a position above the drive circuit portion of the sealing substrate,
When calcium oxide is filled, if the thickness of the desiccant made of calcium oxide is 77 μm, the volume of the desiccant is 4 μm.
1.7 mm ³ , which penetrates from the adhesive layer 1
An amount that can completely absorb water for 0 years can be filled. Since the thickness of the desiccant in this embodiment is 80 μm, there is a sufficient amount of desiccant in terms of calculation for long-term use (use for at least 10 years).

Since the amount of moisture passing through the sealant varies depending on the temperature and humidity, the amount of the desiccant used in the present invention may be determined as appropriate according to the use environment of the display device.

[Embodiment 2] In this embodiment, an example is shown in which a desiccant and a moisture-permeable film are provided above a drive circuit portion. In the present embodiment, points different from the first embodiment will be described in detail. This embodiment will be described with reference to the cross-sectional view of FIG.
FIG. 2 is a cross-sectional view of an active-matrix display device using an active-matrix organic light-emitting element, which has a driving circuit integrated structure in which a pixel portion 112 and a driving circuit portion 111 are formed over the same substrate. .

As the first substrate 101 and the second substrate 102, substrates made of glass can be used.

In the present embodiment, a granular material is used as the drying agent 107. When the desiccant is granulated, the surface area increases,
It becomes easier to adsorb moisture. Particle size of desiccant is 10-8
Desirably, it is 0 μm. In this embodiment, 30 μm
A desiccant having a particle size of m is used. In the present embodiment, the third region 105 where the desiccant is provided is the second region 10.
4 has a depth of 100 μm. The desiccant uses calcium oxide.

In order to confine the desiccant in the third region 105, a moisture-permeable film composed of the adhesive layer 125, the porous layer 126, and the substrate 127 is used. The base material is polyester,
For the porous layer, a polyfluorinated ethylene fiber can be used. The porous film is made of Nitto Denko with high moisture permeability.
TF1121 (JIS K 7129 MethodA)
It is preferable to use 6800 g / m < ² >. Further, the thickness of the moisture-permeable film is preferably 150 μm to 300 μm. In this embodiment, the thickness of the moisture-permeable film is 150 μm.

Also, a gap of about 50 μm is provided between the moisture-permeable film and the drive circuit so that the TFT of the drive circuit does not come into contact with the moisture-permeable film. For this reason, considering the thickness (150 μm) of the moisture-permeable film and the distance between the moisture-permeable film and the drive circuit section, the first
A second region 104 on which a moisture-permeable film is provided is recessed by 200 μm with respect to the region 103.

It is desirable that the layer 106 having an adhesive property for bonding the first substrate and the second substrate be as thin as possible. In the present embodiment, the thickness of the adhesive layer is 1.5 μm.

In order to reduce the volume of the sealed space surrounded by the first substrate, the second substrate, and the adhesive layer, and to reduce the total amount of moisture remaining in the dry gas in the sealed space, a driving circuit It is preferable that the distance between the first substrate and the second substrate in the pixel portion be smaller than the distance between the first substrate and the second substrate in the portion. Since the pixel portion is not particularly limited by providing a moisture-permeable film, the distance between the substrates in the pixel portion can be arbitrarily determined in consideration of the visibility of the display region and the like. In the present embodiment, the distance between the first substrate and the second substrate in the pixel portion is set to 50 μm.

In this embodiment, the organic light emitting device 116 is
An anode 113, an organic compound layer 114, and a cathode 115 are stacked in this order. By using a transparent electrode made of ITO for the anode and an alkaline earth metal such as MgAg or an alkali metal such as AlLi as the metal having a small work function for the cathode, light emission of the organic light emitting element is emitted from the first substrate 101 side. Configuration. The organic compound layer is stacked in the order of a hole transport layer, a light emitting layer, and an electron transport layer. It is preferable to form three types of light emitting layers corresponding to RGB so that color display is possible.

Assuming that the thickness of the second substrate is 0.7 mm,
The thickness of the substrate in the first region is 0.7 mm, the thickness of the substrate in the second region is 0.5 mm, and the thickness of the substrate in the third region is 0.5 mm.
4 mm. Since the second substrate occupies a large area in the second substrate, it can be considered that the thickness and weight of the second substrate are almost determined by the thickness of the glass substrate in the second region. That is, in the second region that occupies most of the substrate, the thickness of the glass substrate of 0.5 mm is a preferable value in terms of reducing the thickness and weight of the display device.

Further, according to the structure of the present embodiment, a granular desiccant having a large surface area and a high hygroscopicity can be provided in the sealing region by using a moisture-permeable film. Further, in the present embodiment, the desiccant is provided on the drive circuit portion, but it is also possible to provide the desiccant on the pixel portion. This is because, considering the direction of light emitted from the organic light emitting element, even if the desiccant is provided on the pixel portion, there is no effect on display.

[Embodiment 3] This embodiment will be described with reference to FIG. FIG. 3 shows a display device provided with an organic light-emitting element 116, in which fine unevenness is formed on the surface of a substrate from which light emitted from the organic light-emitting element is emitted. Hereinafter, the present embodiment will be described in detail.

In this embodiment, the organic light emitting device 116 is
The cathode 113, the organic compound layer 114, and the anode 115 are stacked in this order, and the light emitted from the organic light emitting element 116 is emitted to the side indicated by the arrow in the figure. That is, the user views the image from the second substrate 102 side. At this time, since external light is reflected at the interface between the second substrate 102 and the sealing space and the interface between the second substrate and air, the surrounding scenery is reflected. In order to prevent this reflection, fine irregularities are formed on the surface of the second substrate.

When the surface of the substrate is processed by the abrasive processing method, the first region and the second region 104 are formed on the surface of the second substrate.
After the formation of the third region, the particle size and the spraying speed of the fine powder to be sprayed on the surface of the substrate are adjusted so that the fine irregularities are formed on the surfaces of the first region, the second region and the third region. What is necessary is just to form. The height of the fine unevenness is 0.1 μm to 3 μm, preferably 0.1 μm to 0.5 μm. Further, it is preferable to provide unevenness having different curvatures in order to prevent diffraction, so as to enhance scattering. If the interval (pitch) between the tip of the protrusion and the tip of the protrusion adjacent to the protrusion is (X), X = 0.05
１1 μm (preferably 0.3-0.8 μm). That is, if the pitch is set so as to substantially match the wavelength of visible light, diffused reflection of reflected light can be effectively generated.

Further, in this embodiment, when the user visually recognizes the image formed by the organic light emitting element, external light is reflected at the interface between the second substrate and air, and the surrounding scene is prevented from being reflected. For this purpose, an antireflection film 128 is formed at the interface between the second substrate and air. In the case of a display device capable of color display, since light of three colors RGB is emitted, the antireflection film has a wide band wavelength (400 nm to 7
00 nm), preferably less than 1%, preferably 0.1%.
It is desirable that the content be 5% or less.

According to the present embodiment, the reflected light at the interface between the second substrate and the sealing space is scattered by the fine unevenness. In combination with the effect of the antireflection film provided on the surface of the second substrate, it is possible to prevent the scene around the second substrate from being reflected at the interface of the second substrate and recognized by the user.

[0111]

[Embodiment 1] The present invention can be applied to any display device using an organic light emitting device. FIG. 4 illustrates an example of such an active matrix display device manufactured using TFTs. The TFT of the embodiment may be distinguished from the amorphous silicon TFT or the polysilicon TFT depending on the material of the semiconductor film forming the channel formation region. However, if the field effect mobility is sufficiently high, the present invention can be applied to either of them. can do.

The drive circuit section 437 has an n-channel TFT 4
31 and a p-channel TFT 432 are formed.
38 is a switching TFT 433 and a reset TFT
434, a current control TFT 436 and a storage capacitor 435 are formed.

The substrate 401 is made of quartz or Corning # 7.
A substrate made of glass such as barium borosilicate glass represented by 059 glass or # 1737 glass or aluminoborosilicate glass is used.

Next, a base film 402 made of an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film is provided. For example, the plasma CVD method
H _4, NH _3, silicon oxynitride is formed from N ₂ O film 402a of 10 to 200 nm (preferably 50~100n
m) Then, a silicon oxynitride hydride film 402b similarly made of SiH ₄ and N ₂ O is formed to a thickness of 50 to 200 nm (preferably 100 to 150 nm). Although the base film 402 has a two-layer structure in this embodiment, the base film 402 may be formed as a single-layer film of the insulating film or a structure in which two or more layers are stacked.

Next, island-shaped semiconductor layers 403 to 407, a gate insulating film 408, and gate electrodes 409 to 412 are formed. The thickness of the island-shaped semiconductor films 403 to 407 is 10 to 150.
nm, the gate insulating film has a thickness of 50 to 200 nm, and the gate electrode has a thickness of 50 to 800 nm.

Next, an interlayer insulating film 413 having a laminated structure of an insulating film made of an inorganic material such as silicon nitride or silicon oxynitride and an insulating film made of an organic material such as acrylic or polyimide is formed. I do. The thickness of the interlayer insulating film is preferably 1 to 3 μm. The insulating film made of an organic material is the island-shaped semiconductor films 403 to 407, the gate electrode 4
It is desirable that the thickness be sufficient to flatten the unevenness caused by the components 09 to 412.

Next, a cathode 423 of the organic light emitting device is formed. It is preferable to use a material such as MgAg or LiF for the cathode. The thickness of the cathode is preferably 100 nm to 200 nm.

Next, a conductive film containing aluminum as a main component and having a thickness of 1 to 5 μm is formed and etched. Thereby, in the pixel portion, the data wiring 4
18, a drain side wiring 419, a power supply wiring 420,
An electrode 421 on the drain side is formed. Data wiring 418
Is connected to the source side of the switching TFT 433, and the drain side wiring 419 connected to the drain side of the switching TFT 433 is not shown, but is not shown.
6, the power supply wiring 420 is connected to the drain side of the current control TFT 436, and the drain side electrode 421 is connected to the source side and the cathode of the current control TFT 436. Drive circuit section 437
Means that the wiring 414 and the wiring 416 are n-channel TFT4
The wiring 415 and the wiring 417 are connected to the island-shaped semiconductor film 404 of the p-channel TFT 432. In this embodiment, the conditions for etching the conductive film containing aluminum as a main component are adjusted, and the side surfaces of these wirings are formed at 15 ° to 70 ° with respect to the surface (upper surface) of the interlayer insulating film. With a taper. Light emitted from the organic light-emitting element radiated in random directions is reflected on the side surfaces of these wirings to prevent total reflection.

Next, a bank 422 made of an insulating material is formed so as to cover these wirings. Bank 422 is
The cathode 423 is formed so as to cover the end of the cathode 423, and prevents the cathode and the anode from being short-circuited at this portion. In this embodiment,
A thickness of 1 using an inorganic material such as silicon oxide or silicon oxynitride;
A bank of about 3 μm is formed. Since the inorganic insulating film is formed parallel to the tapered surface of the drain-side electrode 421 or the like, it is easy to predict the traveling direction of the reflected light using Snell's law.

Next, the organic compound layer 42 of the organic light emitting device
4 is formed. The organic compound layer is used in a single layer or a laminated structure, but the luminous efficiency is better when used in a laminated structure. In general, a hole injection layer / a hole transport layer / a light emitting layer / an electron transport layer are formed in this order on the anode, but a hole transport layer / a light emitting layer / an electron transport layer, or a hole injection layer / a hole A structure such as a transport layer / light emitting layer / electron transport layer / electron injection layer may be used. In the present invention, any known structure may be used.

In this embodiment, color display is performed by a method of depositing three kinds of light emitting layers corresponding to RGB. As specific light emitting layers, cyanopolyphenylene may be used for a light emitting layer emitting red light, polyphenylenevinylene may be used for a light emitting layer emitting green light, and polyphenylenevinylene or polyalkylphenylene may be used for a light emitting layer emitting blue light. The thickness of the light emitting layer may be 30 to 150 nm. The above example is an example of an organic compound layer that can be used as a light emitting layer, and the present invention is not limited to this.

The organic compound layer shown in this embodiment has a structure in which a light emitting layer and a hole injection layer made of PEDOT (poly (3,4-thioethylenedioxythiophene) or PAni (polyaniline) are laminated.

Next, ITO (indium tin oxide)
An anode 425 is formed. As described above, Mg
An organic light emitting device including a cathode formed using a material such as Ag or LiF, an organic compound layer in which a light emitting layer and a hole transport layer are laminated, and an anode formed of ITO (indium tin oxide) is provided. . Note that by using a transparent electrode for the anode, light can be emitted toward the sealing substrate (second substrate) 427 in FIG.

The outer edge of the sealing substrate 427 is convex with respect to the first substrate. The gap between the organic light emitting element provided on the first substrate and the second substrate in the pixel portion 438 is adjusted by the convex portion. Since the gap is determined by the convex outer edge portion of the sealing substrate, the adhesive layer 439 provided between the sealing substrate and the element substrate can be made as thin as possible. In this embodiment, the thickness of the adhesive layer is set to 1.0 μm.

As the sealing substrate and the element substrate provided with the organic light emitting element 426, a substrate made of glass is used. However, in this embodiment, a desiccant 429 is provided in the sealing region by processing the surface of the sealing substrate. For this reason, as in the case where a metal substrate is used as the sealing substrate, moisture in the sealing region can be adsorbed by the desiccant. Desiccant 4
29 is wrapped in a porous film 430. The porous film is bonded to a desiccant by an adhesive 428.
An adhesive 440 is applied to a portion where the porous film is hollowed out and the desiccant is exposed, and is adhered to the sealing substrate 427.

FIG. 5 is a top view of the pixel portion shown in FIG. 4, and is denoted by the same reference numerals as in FIG. 4 for convenience. In FIG. 5, a cross section corresponding to the line AA ′ and the line BB ′ is shown in FIG. Note that a bank is provided outside a region surrounded by a chain line. Further, a light emitting layer corresponding to RGB is provided inside a region surrounded by a chain line.

FIG. 6 shows an equivalent circuit of such a pixel portion, and the same reference numerals as in FIG. 4 are used for convenience. The switching TFT 433 has a multi-gate structure, and the current control TFT 436 is provided with an LDD overlapping with the gate electrode. TFT using polysilicon
Has a high operating speed, and is liable to deteriorate such as hot carrier injection. Therefore, forming a TFT having a different structure (a switching TFT having a sufficiently low off-current and a current control TFT having a strong resistance to hot carrier injection) having a different structure in a pixel has high reliability.
Moreover, it is very effective in manufacturing a display device capable of displaying a good image (having high operation performance).

Further, even after the switching TFT 433 changes from the conducting state to the non-conducting state, the current controlling T
It is effective to provide a storage capacitor (capacitor) 435 in order to maintain the FT 436 in the conductive state, keep the organic light-emitting element emitting light, and obtain a display with high luminance.

Further, in the time-division gray scale method in which gradation is displayed by changing the time width of light emission of the organic light emitting element, the resetting TFT 432 is turned on, and the organic light emitting element is turned off from the light emitting state. It is preferable to control the time width of light emission of the organic light emitting element by changing to the state of (1).

In a display device using such an organic light emitting device, by providing a drying agent close to the organic light emitting device, deterioration of the organic light emitting device can be prevented and long-term stability of the display device can be ensured. it can. In addition, since the gap can be controlled using the sealing substrate, the thickness of the adhesive layer provided between the sealing substrate and the element substrate can be reduced as much as possible. Therefore, the area where the adhesive layer is exposed to the outside air is reduced, and the amount of water vapor passing through the adhesive layer can be reduced.

[Embodiment 2] In this embodiment, when a mother substrate (mother glass) corresponding to an area obtained by combining a large number of unit panels is bonded and cut into individual panels, a means for cutting is used. An example using a CO ₂ laser will be described.

The CO ₂ laser is a laser using carbon dioxide as a reaction medium, and is operated by setting carbon dioxide in an excited state and in an inverted distribution state. Infrared wavelength (1
(0.6 nm), the object to be irradiated with the laser light can be heated.

A method of cutting a glass substrate using a CO ₂ laser will be described with reference to the perspective view of FIG. FIG. 9 is a perspective view showing a method of cutting one of the bonded glass substrates 501 to 502. Glass substrate 50 moving in the direction of the arrow
1 is irradiated with an elliptical laser beam spot by an optical system 504 that irradiates a laser, and a coolant is blown by a nozzle 507 to a portion (cooling portion 506) behind the beam spot 503. As described above, the portion heated by the laser irradiation is rapidly cooled next, so that thermal distortion occurs inside the glass substrate, and the glass substrate 501 is divided along the laser irradiation line 505.

As a device for cutting a glass substrate using a CO ₂ laser, a laser scriber manufactured by Samsung Diamond Industrial Co., Ltd. can be used. Two mother substrates (mother glass) may be cut at the same time, or the mother substrates (mother glass) may be cut one by one. It is preferable to cut two sheets at the same time because the tact time of the process is improved and productivity is increased.

By irradiating the glass substrate surface with a CO ₂ laser for cutting, the generation of cutting chips on the glass substrate can be suppressed, and the occurrence of defects can be prevented. In addition, the substrate cutting method using a CO ₂ laser uses laser irradiation and injection of a cooling medium in combination, so that the impact applied to the substrate is small. For this reason,
When the impact resistance of the substrate is reduced as the display device becomes thinner, a method of dividing the glass substrate using a CO ₂ laser is effective.

[Embodiment 3] A light emitting device formed by carrying out the present invention is incorporated in various electric appliances, and a pixel portion is used as an image display portion. As the electronic device of the present invention, a mobile phone, a PDA, an electronic book, a video camera, a notebook personal computer, an image reproducing device equipped with a recording medium,
For example, DVD (Digital Versatile Disc) player,
Digital camera, and the like. Specific examples of these electronic devices are shown in FIGS.

FIG. 10A shows a mobile phone, which includes a display panel 9001, an operation panel 9002, and a connection portion 9003.
The display panel 9001 includes a display device 900.
4, an audio output unit 9005, an antenna 9009, and the like. An operation key 900 is provided on the operation panel 9002.
6, a power switch 9007, a voice input unit 9008, and the like. The invention can be applied to the display device 9004.

FIG. 10B shows a mobile computer or a portable information terminal.
02, an image receiving section 9203, operation switches 9204, and a display device 9205. The present invention relates to a display device 920.
5 can be applied. Such electronic devices include:
Although a display device of a 3 inch to 5 inch class is used, the weight of the portable information terminal can be reduced by using the display device of the present invention.

FIG. 10C shows a portable book, and a main body 93.
01, a display device 9303, a storage medium 9304, operation switches 9305, and an antenna 9306,
Data stored on a mini disk (MD) or DVD,
This is for displaying the data received by the antenna. The present invention can be used for the display device 9303. As the portable book, a display device of a class of 4 inches to 12 inches is used. By using the display device of the present invention, the weight and thickness of the portable book can be reduced.

FIG. 10D shows a video camera, which includes a main body 9401, a display device 9402, an audio input portion 9403, operation switches 9404, a battery 9405, and the like. The present invention can be applied to the display device 9402.

FIG. 11A shows a personal computer, which includes a main body 9601, an image input section 9602, and a display device 9.
603 and a keyboard 9604. The present invention can be applied to the display device 9603.

FIG. 11B shows a player that uses a recording medium (hereinafter, referred to as a recording medium) on which a program is recorded, and includes a main body 9701, a display device 9702, and a speaker unit 97.
03, a recording medium 9704, and operation switches 9705. This device uses a DVD (Digi
(tal Versatile Disc), CDs, etc., to enjoy music, movies, games and the Internet. The present invention can be applied to the display device 9702.

In the operation of the mobile phone shown in FIGS. 10A and 10B, the power consumption is reduced by increasing the luminance when using the operation keys and decreasing the luminance after using the operation switches. can do. The power consumption can also be reduced by increasing the brightness of the display device when an incoming call is received and decreasing the brightness during a call. In addition, when the device is continuously used, the power can be reduced by providing a function of turning off the display by time control unless resetting is performed. Note that these may be manually controlled.

Although not shown here, the present invention can also be applied as a display device incorporated in a navigation system, a refrigerator, a washing machine, a microwave oven, a fixed telephone, a facsimile, and the like. As described above, the applicable range of the present invention is extremely wide, and can be applied to various products.

[0145]

As described above, by using the present invention, it is possible to control the gap at the convex portion of the sealing substrate, and to obtain a layer having an adhesive property between the sealing substrate and the element substrate. Can be made as thin as possible. For this reason,
The area of the side surface of the display device where the organic resin material (having adhesiveness) is exposed to the outside air is reduced. Along with this, it is indicated by the product of the area exposed to the outside air and the moisture permeability, and the amount of moisture that passes through the organic resin material and enters the sealing region can be reduced.

Conventionally, in order to provide a desiccant in the sealing area,
It was necessary to bond a metal sealing substrate and a glass substrate. For this reason, when the impact resistance decreases with the thinning of the glass substrate, the difference in the thermal expansion coefficient between metal and glass causes
Strain is generated by a sudden change in heat, and the glass substrate may be damaged. However, according to the present invention, the sealing substrate and the element substrate can be formed of the same material, and resistance to thermal shock is improved. In addition, since the surface of the glass substrate is processed and a desiccant is provided, moisture is absorbed by the desiccant, and the emission luminance is reduced due to the moisture, as in the related art.
It is possible to suppress the occurrence of a dark spot, a decrease in the light emitting area due to the enlargement of the dark spot, and the deterioration of the element.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a display device using an organic light-emitting element of Embodiment 1.

FIG. 2 is a cross-sectional view of a display device using the organic light-emitting element of Embodiment 2.

FIG. 3 is a cross-sectional view of a display device using the organic light-emitting device of Embodiment 3.

FIG. 4 is a cross-sectional view of a display device using the organic light emitting device of Example 1.

FIG. 5 is a top view illustrating a configuration of a pixel portion of a display device using the organic light-emitting element of Example 1.

FIG. 6 is an equivalent circuit of a pixel portion of a display device using the organic light emitting device of Example 1.

FIG. 7 is a cross-sectional view illustrating the method for manufacturing the sealing substrate of Embodiment 1.

FIG. 8 is a cross-sectional view of a display device using the organic light-emitting device of the present invention.

FIG. 9 is a perspective view showing a method for cutting a glass substrate using a CO ₂ laser.

FIG. 10 illustrates an example of an electronic device.

FIG. 11 illustrates an example of an electronic device.

FIG. 12 shows the surface of a second substrate of the display device according to the third embodiment.

Claims (21)

[Claims] A first substrate provided with an organic light-emitting element;
A second substrate having a light-transmitting property, wherein the first substrate and the second substrate are bonded to each other using a layer having an adhesive property; The surface facing the substrate is the first
And a second region, wherein the first region is bonded with the adhesive layer, and the second region is the first region.
A display device which is inside the region and is concave with respect to the first region. 2. A first substrate provided with an organic light emitting element,
A second substrate having a light-transmitting property, wherein the first substrate and the second substrate are bonded to each other using a layer having an adhesive property; The surface facing the substrate is the first
, A second region, and a third region, wherein the first region has the adhesive layer adhered thereto, and the second region is inside the first region. The third region is concave with respect to the first region, the third region is inside the second region and concave with respect to the second region, and the third region is concave with respect to the second region.
A display device, wherein a desiccant is provided in a region of (1). 3. A display according to claim 2, wherein a moisture-permeable film is provided so as to adhere to a part of said second region and to confine said desiccant in said third region. apparatus. 4. A first substrate provided with an organic light emitting device,
An adhesive layer that surrounds a region of the first substrate on which the organic light emitting element is provided with a gap, and a light-transmitting second substrate; The second substrate is attached using the layer having the adhesive property, and a surface of the second substrate facing the first substrate is a first surface.
, A second region, and a third region, wherein the first region is adhered to the layer having the adhesive property, and the second region is surrounded by the first region. The third region is concave with respect to the first region, and the third region is concave between the adhesive layer and the region where the organic light emitting element is provided and is concave with respect to the second region. A display device, wherein a desiccant is provided in the third area. 5. The moisture-permeable film according to claim 4, wherein a moisture-permeable film is provided between the adhesive layer and a region above the region where the organic light-emitting element is provided. Wherein the desiccant is adhered to a part of the third region and the desiccant is confined in the third region. 6. The film according to claim 3, wherein the moisture-permeable film adhered to the second region is between a plane contacting the first region and a surface contacting the second region. A display device characterized in that the display device fits into a display device. 7. The device according to claim 2, wherein a difference in height between a bottom of the second region which is concave with respect to the first region and the first region is not less than 10 μm and not more than 50 μm.
A display device characterized by the following. 8. The method according to claim 3, wherein a difference between the height of the first region and the bottom of the second region, which is concave with respect to the first region, is 160 μm or more.
A display device having a thickness of not more than μm. 9. The device according to claim 1, wherein a difference between a height of the second region and a bottom of the third region, which is concave with respect to the second region, is 50 μm to 150 μm.
A display device characterized by the following. 10. The display device according to claim 1, wherein the first substrate or the second substrate is a glass substrate. 11. The second substrate according to claim 1, wherein the second substrate is provided with irregularities, and a distance between a projecting portion and a tip of the projecting portion adjacent to the projecting portion is 0.1 mm. A display device characterized by being in the range of 0.5 to 1 μm. 12. The display device according to claim 1, wherein the thickness of the adhesive layer is 10 μm or less. 13. A display device in which a first substrate having a light-transmitting property and a second substrate are attached to each other with an adhesive layer, and an organic light-emitting element is provided on the first substrate. In the manufacturing method, a region of the second substrate to which the layer having the adhesive property is adhered is defined as a first region, and at least the first region is formed in the first region.
A first step of providing a mask; a second step of excavating the second substrate by an abrasive processing method to form a second region that is concave with respect to the first region; A third step of removing the first mask; and a second mask formed on at least a region of the second substrate where the first mask is provided and a region above the region where the organic light emitting element is provided. A fourth step of excavating the second substrate by a sand processing method to form a third region that is concave with respect to the second region; and drying a desiccant in the third region. And a fifth step of providing a display device. 14. The method for manufacturing a display device according to claim 13, further comprising a sixth step of providing a moisture-permeable film in the second region after the fifth step. 15. The method according to claim 14, wherein the excavation depth of the second substrate in the second step is deeper than the thickness of the moisture-permeable film. . 16. The method for manufacturing a display device according to claim 13, wherein the excavation depth in the second step is 10 μm or more and 50 μm or less. 17. The method for manufacturing a display device according to claim 14, wherein the depth of the excavation in the second step is 160 μm or more and 350 μm or less. 18. The method for manufacturing a display device according to claim 13, wherein the depth of the excavation in the fourth step is 50 μm or more and 150 μm or less. 19. The method according to claim 13, wherein, after the fifth step, a sixth step of bonding the first substrate and the second substrate using the adhesive layer. And a seventh step of cutting the first substrate and the second substrate using a gas laser. 20. The method according to claim 14, wherein after the sixth step, the first substrate and the second substrate are bonded to each other by using the layer having the adhesive property. 7. A method for manufacturing a display device, comprising: a seventh step; and an eighth step of cutting the first substrate and the second substrate using a gas laser. 21. The method according to claim 19, wherein the gas laser is a CO ₂ laser.