KR20170068235A - Barrier film, method of fabricating the same and Organic light emitting diode display device including the same - Google Patents

Abstract

In the present invention, by providing the barrier film in which the liquid moisture absorber is dispersed in a droplet form in the polymer, the moisture barrier property and the impact relaxation property of the barrier film are improved.
Accordingly, it is possible to provide an organic light emitting diode display device in which damage to the light emitting diode due to external moisture permeation is minimized.

Description

[0001] The present invention relates to a barrier film, a method of manufacturing the same, and an organic light emitting diode (OLED)

The present invention relates to an organic light emitting diode display, and more particularly, to a barrier film having excellent moisture characteristics, a method of manufacturing the same, and an organic light emitting diode display device capable of preventing damage to the light emitting diode, including a barrier film.

As the information society develops, the demand for display devices for displaying images is increasing in various forms. A liquid crystal display (LCD) device, a plasma display panel (PDP), or an organic light emitting diode (OLED), which is thinner and lighter than a conventional cathode ray tube (CRT) )) Display device is actively researched and commercialized.

Of these flat panel display devices, organic light emitting diode display devices have various advantages such as short response time, large contrast ratio, wide viewing angle and low power consumption, and active research is underway to develop them as next generation display devices.

Since the light emitting diode including the organic light emitting layer is very vulnerable to moisture, in order to prevent moisture from the outside from penetrating into the light emitting diode and protect the light emitting diode from external impact, the encapsulation substrate made of glass, Respectively.

Recently, foldable, bendable or rollable display devices (hereinafter, referred to as flexible display devices) capable of bending a display device like paper have been proposed.

In such an organic light emitting diode display device, an encapsulation film in which an inorganic layer and an organic layer are alternately stacked is used instead of an encapsulation substrate made of glass.

1 is a schematic cross-sectional view of a conventional organic light emitting diode display.

1, the organic light emitting diode display device 1 includes a substrate 10 on which a display area AA and a non-display area NA around the display area AA are defined, 10, and an encapsulation film 20 covering the light emitting diode D, as shown in FIG.

The substrate 10 may be made of a polymer such as polyimide, and the light emitting diode D is formed on the substrate 10.

The light emitting diode D is located in the display area AA and a driving unit (not shown) for driving the light emitting diode D is located in the non-display area NA.

Although not shown, the light emitting diode D includes first and second opposing electrodes and an organic light emitting layer positioned between the first and second electrodes. In addition, on the substrate 10, a switching thin film transistor, which is a switching element, and a driving thin film transistor, which is a driving element, are formed for each pixel region, and a first electrode of the light emitting diode D is connected to the driving thin film transistor.

The encapsulation film 20 covers the light emitting diode D and is formed corresponding to the display area AA and the non-display area NA. The encapsulation film 20 prevents the light emitting diode D from being damaged in a high temperature and high humidity environment.

The encapsulation film 20 has a structure in which an inorganic layer and an organic layer are alternately laminated. For example, the encapsulation film 20 may include a first inorganic layer 22 on the light emitting diode D, an organic layer 24 on the first inorganic layer 22, Layer structure composed of the first inorganic layer 26 and the second inorganic layer 26.

The barrier film 30 may be adhered to the encapsulation film 20 through the adhesive layer 32.

For example, each of the first and second inorganic layers 22 and 26 of the encapsulation film 20 is made of an inorganic material such as silicon oxide (SiOx), silicon nitride (SiNx), and aluminum oxide (AlOx) The organic layer 24 of the encapsulation film 20 may be formed of an acryl-based or an expoxy-based organic material.

However, if the organic light emitting diode display device 1 is placed in a high temperature and high humidity environment, the light emitting diode D is damaged, and the display quality of the organic light emitting diode display device 1 deteriorates and / do.

The present invention aims at solving the problem of display quality deterioration and shortening of life span in an organic light emitting diode display device due to damage of a light emitting diode.

In order to solve the above problems, the present invention provides a barrier film comprising a droplet-shaped liquid-phase moisture absorber in a polymer matrix.

The present invention also provides an organic light emitting diode device including the above-mentioned barrier film and a method of manufacturing the above-mentioned barrier film.

The barrier film according to the present invention has excellent moisture barrier properties and impact resistance by dispersing the liquid moisture absorber in a droplet form in a cured polymer matrix.

In addition, the barrier film of the present invention includes a first layer in which a liquid moisture absorbent is dispersed in a droplet form in a cured polymer, and a second layer and a second layer, which are positioned below and above the first layer, And the moisture barrier property of the barrier film is further improved.

In addition, the barrier film of the present invention is used in an organic light emitting diode display device to cover a light emitting diode, thereby minimizing damage to the light emitting diode.

1 is a schematic cross-sectional view of a conventional organic light emitting diode display.
2 is a schematic cross-sectional view of a barrier film according to a first embodiment of the present invention.
3 is a schematic view for explaining the moisture permeation characteristics of the barrier film according to the first embodiment of the present invention.
4 is a schematic cross-sectional view of an organic light emitting diode display device according to a second embodiment of the present invention.
5 is a schematic cross-sectional view showing a pixel region including a light emitting diode.
6 is a schematic cross-sectional view of an organic light emitting diode display device according to a second embodiment of the present invention.
7 is a schematic cross-sectional view of a barrier film according to a third embodiment of the present invention.
8 is a schematic cross-sectional view of an organic light emitting diode display device according to a fourth embodiment of the present invention.
9A and 9B are schematic cross-sectional views illustrating a manufacturing process of a barrier film according to a fifth embodiment of the present invention.

In the conventional organic light emitting diode display device, an encapsulation film composed of a first inorganic film, an organic film, and a second inorganic film is used to prevent moisture from penetrating into the light emitting diode.

However, since the organic film serves to mitigate the stress of the inorganic film and to compensate for the step difference, it does not have a direct moisture barrier characteristic and extends the water's path of progression to delay water penetration, so that the encapsulation film has a sufficient moisture barrier property I do not have.

In addition, since the first and second inorganic films constituting the encapsulation film and the organic film have a relatively large modulus value, damage such as cracks is easily generated in the encapsulation film due to an external impact, So that the light emitting diode can be damaged.

That is, the encapsulation film used in the conventional organic light emitting diode display has insufficient moisture barrier properties and insufficient impact resistance characteristics.

In order to solve the above-mentioned problems, the present invention provides a barrier film comprising a polymer having a void space and a first layer on which a liquid-phase moisture absorber in the void space is exposed.

According to another aspect of the present invention, there is provided a barrier film comprising a polymer having a void space, an organic layer including a liquid moisture absorbent in the void space, and a barrier film according to the present invention of the organic layer, And a second layer and a third layer made of a material.

In the barrier film according to the embodiment of the present invention, the liquid moisture absorber may have a hydroxyl group.

In the barrier film according to the embodiment of the present invention, the liquid moisture absorber may be glycerin.

In the barrier film according to the embodiment of the present invention, the size of the liquid moisture absorber may be 400 nm or less.

In the barrier film according to the embodiment of the present invention, the size of the liquid humidifying agent may be 400 to 700 nm, and the refractive index difference between the polymer and the liquid humidifying agent may be 0.01 or less.

In the barrier film according to the embodiment of the present invention, the liquid humidifying agent may have a first size in the first region and a second size larger than the first size in the second region.

In another aspect, the present invention provides an organic light emitting diode display device including a substrate, a light emitting diode disposed on the substrate, and the above-described barrier film covering the light emitting diode.

According to still another aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, comprising: forming an organic material layer by coating an organic material including a monomer, a liquid moisture absorber and a photoinitiator; And a step in which the moisture absorbent is agglomerated.

In the barrier film production method according to the embodiment of the present invention, the size of the agglomerated liquid-phase moisture absorber may be inversely proportional to the intensity of the UV.

In the method for producing a barrier film according to an embodiment of the present invention, the size of the flocculated liquid-phase moisture absorber may be proportional to the process temperature of the UV irradiation step.

In the method of producing a barrier film according to an embodiment of the present invention, the liquid humidifying agent may have a first size in the first region and a second size in the second region larger than the first size.

Hereinafter, the present invention capable of solving the above problems will be described in detail with reference to the drawings.

- First Embodiment -

FIG. 2 is a schematic cross-sectional view of a barrier film according to a first embodiment of the present invention, and FIG. 3 is a schematic view for explaining the moisture permeation characteristics of the barrier film according to the first embodiment of the present invention.

2, the barrier film 100 according to the first embodiment of the present invention includes a polymer 110 having an empty space 120 and a liquid humidifying agent 130 disposed in the empty space 120. [ . That is, the polymer 110 including the liquid moisture absorbent 130 dispersed in a droplet form constitutes the barrier film 100 and has a moisture barrier property by the liquid moisture absorber 130.

The polymer 110 may be an epoxy-based polymer, an acryl-based polymer, or a silicon-based polymer.

The liquid-phase moisture absorber 130 is made of a material having a hydroxyl group and having a liquid state at about 0 to 100 ° C. For example, the liquid moisture absorbent 130 may be glycerin.

The size of the void space 120, that is, the droplet size of the liquid moisture absorbent 130 may be smaller than the wavelength of visible light. For example, the droplet size of the liquid moisture absorbent 130 may be smaller than 400 nm. Preferably, the droplet size of the liquid humidifying agent 130 may be smaller than 200 nm. Therefore, even if the liquid humectant 130 filling the polymer 110 and the empty space 120 has a different refractive index, no haze occurs and the transmittance of the barrier film 100 is not reduced.

On the other hand, the droplet size of the liquid moisture absorbent 130 may be larger than the visible light wavelength. In this case, the refractive index of the polymer 110 and the liquid-phase moisture absorber 130 can be controlled to prevent the occurrence of haze. For example, when the droplet size of the liquid humidifying agent 130 is 400 nm to 700 nm, the refractive index difference between the polymer 110 and the liquid humidifying agent 130 may be 0.01 or less so that the occurrence of haze can be minimized.

When water is permeated into the barrier film 100 according to the first embodiment of the present invention, the water molecules are combined with the liquid moisture absorbent 130 and become trapped in the void space 120. That is, water molecules are trapped by the liquid moisture absorbent 130, and the barrier film 100 has a characteristic of preventing moisture permeation or delaying the moisture permeation.

More specifically, referring to FIG. 3, the hydrogen of the hydroxyl group (OH) in the liquid phase moisture absorber as glycerin has a positive electronegativity (delta ⁺ ) and the oxygen of the water molecule has a negative electronegativity (delta ^- ) , The hydroxyl group of glycerin and the oxygen of the water molecule become strong hydrogen bonds.

Therefore, permeation of moisture by the barrier film 100 is prevented.

Also, since the polymer 110 has a plurality of empty spaces 120 and the empty space 120 is filled with the liquid humidifying agent 130, the modulus value of the barrier film 100 is reduced. Therefore, damage of the barrier film 100 due to an external impact is prevented or minimized.

On the other hand, when the solid-phase moisture absorber is dispersed in the polymer to form a barrier film, the modulus of the barrier film increases, and the impact resistance characteristic is lowered.

As described above, in the barrier film 100 of the present invention, since the droplet-shaped liquid-phase moisture absorber 130 is dispersed in the cured polymer (110) matrix, the barrier film 100 having improved moisture barrier properties and impact resistance characteristics, Can be provided.

- Second Embodiment -

FIG. 4 is a schematic cross-sectional view of an organic light emitting diode display according to a second embodiment of the present invention, FIG. 5 is a schematic cross-sectional view showing one pixel region including a light emitting diode, 1 is a schematic cross-sectional view of an organic light emitting diode display device according to an embodiment.

4, the organic light emitting diode display 200 according to the second embodiment of the present invention includes a substrate 210, a light emitting diode D disposed on the substrate 210, Diode D includes a covering barrier film 220.

Although not shown, a plurality of pixel regions are defined on the substrate 210, and the light emitting diodes D are formed in each pixel region.

5, a gate line GL, a data line DL, and a power line PL are formed on a substrate 210 so as to define a pixel region P intersecting with each other. In the pixel region P, A switching thin film transistor Ts, a driving thin film transistor Td, a storage capacitor Cst, and an organic light emitting diode D are formed.

The switching thin film transistor Ts is connected to the gate wiring GL and the data wiring DL and the driving thin film transistor Td and the storage capacitor Cst are connected between the switching thin film transistor Ts and the power wiring PL. And the organic light emitting diode D is connected to the driving thin film transistor Td.

When the switching thin film transistor Ts is turned on in response to a gate signal applied to the gate line GL, the organic light emitting diode display device is turned on, A data signal is applied to the gate electrode of the driving thin film transistor Td and one electrode of the storage capacitor Cst through the switching thin film transistor Ts.

The driving thin film transistor Td is turned on in accordance with the data signal applied to the gate electrode so that a current proportional to the data signal is supplied from the power wiring PL to the organic light emitting diode D through the driving thin film transistor Td, And the organic light emitting diode D emits light with a luminance proportional to the current flowing through the driving thin film transistor Td.

At this time, the storage capacitor Cst is charged with a voltage proportional to the data signal so that the voltage of the gate electrode of the driving thin film transistor Td is kept constant during one frame.

Therefore, the organic light emitting display device can display a desired image by the gate signal and the data signal.

Referring to FIG. 6, a driving thin film transistor Td is disposed on the substrate 210, a light emitting diode D is disposed on the driving thin film transistor Td, A film 220 is placed on the front surface of the substrate 210.

The substrate 210 may be a glass substrate or a polymer such as polyimide, but is not limited thereto.

Although not shown, a buffer layer made of an inorganic insulating material such as silicon oxide or silicon nitride may be formed on the substrate 210.

The semiconductor layer 252 is formed on the substrate 210, and may be formed of an oxide semiconductor material or polycrystalline silicon.

When the semiconductor layer 252 is made of an oxide semiconductor material, a light shielding pattern (not shown) may be formed under the semiconductor layer 252, and the light shielding pattern may prevent light from being incident on the semiconductor layer 252 Thereby preventing the semiconductor layer 252 from being deteriorated by light. Alternatively, the semiconductor layer 252 may be made of polycrystalline silicon. In this case, impurities may be doped on both edges of the semiconductor layer 252.

A gate insulating layer 254 made of an insulating material is formed on the entire surface of the substrate 210 on the semiconductor layer 252. The gate insulating layer 254 may be formed of an inorganic insulating material such as silicon oxide or silicon nitride.

A gate electrode 260 made of a conductive material such as metal is formed on the gate insulating layer 254 to correspond to the center of the semiconductor layer 252. The gate electrode 260 is connected to the switching thin film transistor Ts.

The gate insulating layer 254 may be formed on the entire surface of the substrate 210. The gate insulating layer 254 may be patterned to have the same shape as the gate electrode 260. [

An interlayer insulating layer 262 made of an insulating material is formed on the entire surface of the substrate 210 on the gate electrode 260. The interlayer insulating layer 262 may be formed of an inorganic insulating material such as silicon oxide or silicon nitride, or may be formed of an organic insulating material such as benzocyclobutene or photo-acryl.

The interlayer insulating film 262 has first and second contact holes 264 and 266 that expose both sides of the semiconductor layer 252. The first and second contact holes 264 and 266 are spaced apart from the gate electrode 260 on both sides of the gate electrode 260.

Here, the first and second contact holes 264 and 266 are also formed in the gate insulating film 254. Alternatively, when the gate insulating layer 254 is patterned to have the same shape as the gate electrode 260, the first and second contact holes 264 and 266 may be formed only in the interlayer insulating layer 262 .

A source electrode 270 and a drain electrode 272 made of a conductive material such as metal are formed on the interlayer insulating layer 262.

The drain electrode 272 and the source electrode 270 are spaced around the gate electrode 260 and are electrically connected to the semiconductor layer 252 through the first and second contact holes 264 and 266, As shown in Fig. The source electrode 270 may be connected to the power line (not shown).

The semiconductor layer 252 and the gate electrode 260, the source electrode 270 and the drain electrode 272 constitute the driving thin film transistor Td, The gate electrode 260, the source electrode 270, and the drain electrode 272 are located on the upper portion of the gate electrode 252.

Alternatively, the driving thin film transistor Td may have an inverted staggered structure in which a gate electrode is located below the semiconductor layer and a source electrode and a drain electrode are located above the semiconductor layer. In this case, the semiconductor layer may be made of amorphous silicon.

Meanwhile, the switching thin film transistor (not shown) may have substantially the same structure as the driving thin film transistor Td.

A protective layer 274 having a drain contact hole 276 exposing the drain electrode 272 of the driving thin film transistor Td is formed covering the driving thin film transistor Td.

A first electrode 280 connected to the drain electrode 272 of the driving TFT Td through the drain contact hole 276 is formed on the protective layer 274 for each pixel region.

The first electrode 280 may be an anode and may be formed of a conductive material having a relatively large work function value. For example, the first electrode 280 may be made of a transparent conductive material such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) .

Meanwhile, when the organic light emitting diode display 100 according to the second embodiment of the present invention is a top emission type, a reflective electrode or a reflective layer may be formed on the bottom and / Can be further formed. For example, the reflective electrode or the reflective layer may be formed of an aluminum-palladium-copper (APC) alloy. That is, the first electrode 280 may have a two-layer structure of a transparent conductive electrode, a reflective electrode, or a reflective layer, or may have a triple-layer structure in which a reflective electrode or a reflective layer is located above and below the transparent conductive electrode.

In addition, a bank layer 286 covering the edge of the first electrode 280 is formed on the protective layer 274. The bank layer 286 exposes the center of the first electrode 280 corresponding to the pixel region.

An organic light emitting layer 282 is formed on the first electrode 280. The organic light emitting layer 282 may have a single layer structure of a light emitting material layer made of a light emitting material. The organic light emitting layer 282 may include a hole injection layer, a hole transporting layer, a light emitting material layer, and an electron transporting layer, which are sequentially stacked on the first electrode 280, (electron transporting layer) and an electron injection layer (multilayer structure).

A second electrode 284 is formed on the substrate 210 on which the organic light emitting layer 282 is formed. The second electrode 284 is disposed on the entire surface of the display region and is made of a conductive material having a relatively small work function value and can be used as a cathode. For example, the second electrode 284 may be formed of any one of aluminum (Al), magnesium (Mg), and aluminum-magnesium alloy (AlMg).

The first electrode 280, the organic light emitting layer 282, and the second electrode 284 form a light emitting diode (D).

A barrier film 220 is formed on the second electrode 284 to prevent external moisture from penetrating the light emitting diode D.

The barrier film 220 includes a polymer 222 having an empty space 224 and a liquid moisture absorbent 226 located in the empty space 224. That is, the barrier film 220 has a single-layer structure made of an organic material.

The polymer 222 may be an epoxy-based polymer, an acrylic-based polymer, or a silicon-based polymer.

The liquid moisture absorber 226 is made of a material having a hydroxyl group and having a liquid state at a temperature of about 0 to 100 ° C. For example, the liquid absorbent 226 may be glycerin.

The size of the void space 224, that is, the droplet size of the liquid moisture absorber 226 may be smaller than the wavelength of visible light. For example, the droplet size of the liquid moisture absorbent 226 may be smaller than 400 nm. Preferably, the droplet size of the liquid moisture absorber 226 may be smaller than 200 nm. Therefore, even if the liquid absorbent 226 filling the empty space 224 and the polymer 222 have a different refractive index, haze is not generated and the transmittance of the barrier film 220 is not lowered.

On the other hand, the drop size of the liquid moisture absorbent 226 may be larger than the visible light wavelength. In this case, the refractive index of the polymer 222 and the liquid-phase moisture absorber 226 can be controlled to prevent the occurrence of haze. For example, when the droplet size of the liquid hygroscopic agent 226 is 400 nm to 700 nm, the refractive index difference between the polymer 222 and the liquid hygroscopic agent 226 is 0.01 or less so that occurrence of haze can be minimized.

As described above, since the barrier film 220 has excellent moisture barrier characteristics and impact relaxation characteristics, in the organic light emitting diode display device 200 according to the second embodiment of the present invention, the light emitting diode D, Is minimized.

That is, as described in FIG. 3, since the hydrogen of the hydroxyl group in the liquid phase moisture absorber has a positive electronegativity (? ⁺ ) And the oxygen of the water molecule has a negative electronegativity (? ^- ), the hydroxyl group of glycerin The oxygen of the water molecule makes a strong hydrogen bond.

Therefore, permeation of moisture by the barrier film 220 is prevented.

Since the barrier film 220 has a small modulus value by the liquid moisture absorbent 226 filling the empty space 224 of the polymer 222, the external impact is absorbed by the barrier film 220. Therefore, direct penetration of moisture and damage of the barrier film 220 due to an external impact are prevented, so that the damage of the light emitting diode D can be minimized.

Therefore, it is possible to provide a high-quality, long-life organic light emitting diode display device 200 which is free from deterioration of display quality and lifetime caused by damages of the light emitting diode D by moisture.

- Third Embodiment -

7 is a schematic cross-sectional view of a barrier film according to a third embodiment of the present invention.

7, the barrier film 300 according to the third embodiment of the present invention includes an organic layer 310 including a liquid moisture absorbent 316, The first and second inorganic layers 320 and 330, respectively.

In the organic layer 310, the liquid moisture absorbent 316 is located in the empty space 314 of the polymer 312. That is, a polymer 312 including a liquid moisture absorbent 316 dispersed in a droplet form forms the organic layer 310, and the organic layer 310 has a moisture barrier property by the liquid moisture absorbent 316.

The polymer 312 may be an epoxy-based polymer, an acrylic-based polymer, or a silicon-based polymer.

The liquid moisture absorbent 316 is made of a material having a hydroxyl group and having a liquid state at a temperature of about 0 to 100 ° C. For example, the liquid absorbent 316 may be glycerin.

The size of the void space 314, that is, the droplet size of the liquid moisture absorber 316 may be smaller than the wavelength of visible light. For example, the droplet size of the liquid moisture absorber 316 may be smaller than 400 nm. Preferably, the droplet size of the liquid moisture absorber 316 may be less than 200 nm. Therefore, even if the liquid absorbent 316 filling the empty space 314 and the polymer 312 have different refractive indices, haze is not generated and the transmittance of the barrier film 300 is not lowered.

On the other hand, the droplet size of the liquid moisture absorber 316 may be larger than the visible light wavelength. In this case, the refractive index of the polymer 312 and the liquid-phase moisture absorber 316 can be controlled to prevent the occurrence of haze. For example, when the droplet size of the liquid hygroscopic agent 316 is 400 nm to 700 nm, a difference in refractive index between the polymer 312 and the liquid hygroscopic agent 316 is 0.01 or less, thereby minimizing the occurrence of haze.

Each of the first and second inorganic layers 320 and 330 is made of an inorganic material such as silicon nitride (SiNx), silicon oxide (SiOx), or aluminum oxide (AlOx). That is, the first and second inorganic layers 320 and 330 serve to prevent water infiltration.

The water molecules are combined with the liquid moisture absorbent 316 of the organic layer 310 and become trapped in the void space 314 when the barrier film 300 according to the third embodiment of the present invention is permeated. That is, water molecules are trapped by the liquid moisture absorbent 316, and the barrier film 300 has a characteristic of preventing moisture permeation or delaying the moisture permeation.

3, since the hydrogen of the hydroxyl group (OH) in the liquid moisture absorber has a positive electronegativity (delta ⁺ ) and the oxygen of the water molecule has a negative electronegativity (delta ^- ), Of the hydroxyl group and oxygen of the water molecule are subjected to strong hydrogen bonding.

Therefore, permeation of moisture by the barrier film 300 is prevented.

In addition, since the polymer 312 has a large number of empty spaces 314 and the empty space 314 is filled with the liquid moisture absorbent 316, the modulus value of the barrier film 300 is reduced. Therefore, damage of the barrier film 300 due to an external impact is prevented or minimized.

As described above, in the barrier film 300 of the present invention, since the droplet-shaped liquid-phase moisture absorber 316 is dispersed in the cured polymer 312, the barrier film 300 having improved moisture barrier properties and impact resistance .

- Fourth Embodiment -

8 is a schematic cross-sectional view of an organic light emitting diode display device according to a fourth embodiment of the present invention.

8, an organic light emitting diode display 400 according to a fourth embodiment of the present invention includes a substrate 410, a light emitting diode D disposed on the substrate 410, The diode D includes a covering barrier film 420.

Although not shown, a plurality of pixel regions are defined on the substrate 410, and the light emitting diodes D are formed in each pixel region.

The substrate 410 may be a glass substrate or a polymer such as polyimide, but is not limited thereto.

Although not shown, a buffer layer made of an inorganic insulating material such as silicon oxide or silicon nitride may be formed on the substrate 410.

The semiconductor layer 452 is formed on the substrate 410, and may be formed of an oxide semiconductor material or polycrystalline silicon.

When the semiconductor layer 452 is made of an oxide semiconductor material, a light shielding pattern (not shown) may be formed under the semiconductor layer 452, and the light shielding pattern may prevent the light from being incident on the semiconductor layer 452 Thereby preventing the semiconductor layer 452 from being deteriorated by light. Alternatively, the semiconductor layer 452 may be made of polycrystalline silicon. In this case, impurities may be doped on both edges of the semiconductor layer 452.

A gate insulating layer 454 made of an insulating material is formed on the entire surface of the substrate 410 on the semiconductor layer 452. The gate insulating layer 454 may be formed of an inorganic insulating material such as silicon oxide or silicon nitride.

A gate electrode 460 made of a conductive material such as metal is formed on the gate insulating layer 454 to correspond to the center of the semiconductor layer 452. The gate electrode 460 is connected to the switching thin film transistor Ts.

The gate insulating layer 454 is formed on the entire surface of the substrate 410. The gate insulating layer 454 may be patterned to have the same shape as the gate electrode 460. [

An interlayer insulating layer 462 made of an insulating material is formed on the entire surface of the substrate 410 on the gate electrode 460. The interlayer insulating film 462 may be formed of an inorganic insulating material such as silicon oxide or silicon nitride, or may be formed of an organic insulating material such as benzocyclobutene or photo-acryl.

The interlayer insulating film 462 has first and second contact holes 464 and 466 that expose both sides of the semiconductor layer 452. The first and second contact holes 464 and 466 are spaced apart from the gate electrode 460 on both sides of the gate electrode 460.

Here, the first and second contact holes 464 and 466 are also formed in the gate insulating film 454. Alternatively, when the gate insulating layer 454 is patterned to have the same shape as the gate electrode 460, the first and second contact holes 464 and 466 may be formed only in the interlayer insulating layer 462 .

A source electrode 470 and a drain electrode 472 made of a conductive material such as a metal are formed on the interlayer insulating layer 462.

The drain electrode 472 and the source electrode 470 are spaced apart from each other around the gate electrode 460 and are electrically connected to the semiconductor layer 452 through the first and second contact holes 464 and 466, As shown in Fig. The source electrode 470 may be connected to the power line (not shown).

The semiconductor layer 452 and the gate electrode 460, the source electrode 470 and the drain electrode 472 constitute the driving thin film transistor Td, The gate electrode 460, the source electrode 470 and the drain electrode 472 are located on the upper portion of the gate insulating layer 452.

Alternatively, the driving thin film transistor Td may have an inverted staggered structure in which a gate electrode is located below the semiconductor layer and a source electrode and a drain electrode are located above the semiconductor layer. In this case, the semiconductor layer may be made of amorphous silicon.

Meanwhile, the switching thin film transistor (not shown) may have substantially the same structure as the driving thin film transistor Td.

A protective layer 474 having a drain contact hole 476 exposing the drain electrode 472 of the driving thin film transistor Td is formed to cover the driving thin film transistor Td.

A first electrode 480 connected to the drain electrode 472 of the driving TFT Td through the drain contact hole 476 is formed on the protective layer 474 for each pixel region.

The first electrode 480 may be an anode and may be formed of a conductive material having a relatively large work function value. For example, the first electrode 480 may be made of a transparent conductive material such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) .

Meanwhile, when the organic light emitting diode display 100 according to the fourth embodiment of the present invention is a top emission type, a reflective electrode or a reflective layer is formed on the bottom and / or top of the first electrode 480, Can be further formed. For example, the reflective electrode or the reflective layer may be formed of an aluminum-palladium-copper (APC) alloy. That is, the first electrode 480 may have a two-layer structure of a transparent conductive electrode, a reflective electrode, or a reflective layer, or may have a triple-layer structure in which a reflective electrode or a reflective layer is positioned above and below the transparent conductive electrode.

A bank layer 486 covering the edge of the first electrode 480 is formed on the passivation layer 474. The bank layer 486 exposes the center of the first electrode 480 corresponding to the pixel region.

An organic light emitting layer 482 is formed on the first electrode 480. The organic light emitting layer 482 may be a single layer structure of a light emitting material layer made of a light emitting material. The organic light emitting layer 482 may include a hole injection layer, a hole transporting layer, a light emitting material layer, and an electron transporting layer sequentially stacked on the first electrode 480. [ (electron transporting layer) and an electron injection layer (multilayer structure).

A second electrode 484 is formed on the substrate 410 on which the organic light emitting layer 482 is formed. The second electrode 484 is disposed on the entire surface of the display region and is made of a conductive material having a relatively small work function value and can be used as a cathode. For example, the second electrode 484 may be formed of any one of aluminum (Al), magnesium (Mg), and aluminum-magnesium alloy (AlMg).

The first electrode 480, the organic light emitting layer 482, and the second electrode 484 form a light emitting diode (D).

A barrier film 440 is formed on the second electrode 484 to prevent external moisture from penetrating the light emitting diode D.

The barrier film 440 includes an organic layer 420 including a liquid moisture absorbent 426 and first and second inorganic layers 432 and 434 located under and over the organic layer 420 respectively. That is, the barrier film 440 has a triple-layer structure.

In the organic layer 420, the liquid moisture absorbent 426 is located in the empty space 424 of the polymer 422. That is, the polymer 422 including the liquid moisture absorbent 426 dispersed in a droplet form constitutes the organic layer 420, and the organic layer 420 has the moisture barrier property by the liquid moisture absorbent 426.

The polymer 422 may be an epoxy-based polymer, an acrylic-based polymer, or a silicon-based polymer.

The liquid moisture absorber 426 is made of a material having a hydroxyl group and having a liquid state at a temperature of about 0 to 100 ° C. For example, the liquid moisture absorbent 426 may be glycerin.

The size of the void space 424, that is, the droplet size of the liquid moisture absorber 426 may be smaller than the wavelength of visible light. For example, the droplet size of the liquid moisture absorber 426 may be smaller than 400 nm. Preferably, the droplet size of the liquid moisture absorber 426 may be smaller than 200 nm. Therefore, even if the liquid moisture absorber 426 filling the empty space 424 and the polymer 422 have different refractive indices, haze is not generated and the transmittance of the barrier film 440 is not lowered.

On the other hand, the droplet size of the liquid moisture absorbent 426 may be larger than the visible light wavelength. In this case, the refractive index of the polymer 422 and the liquid-phase moisture absorber 426 can be controlled to prevent the occurrence of haze. For example, when the droplet size of the liquid humidifying agent 426 is 400 nm to 700 nm, the refractive index difference between the polymer 422 and the liquid humidifying agent 426 may be 0.01 or less so that occurrence of haze can be minimized.

Each of the first and second inorganic layers 432 and 434 is made of an inorganic material such as silicon nitride (SiNx), silicon oxide (SiOx), and aluminum oxide (AlOx). That is, the first and second inorganic layers 432 and 434 prevent moisture permeation.

In FIGS. 7 and 8, the barrier films 300 and 440 of the three-layer structure are shown. Alternatively, the organic layer and the inorganic layer may be disposed under the first inorganic layers 320 and 432, and the organic layer and the inorganic layer may be disposed on the second inorganic layers 330 and 434, It may have a ply structure.

As described above, since the barrier film 440 has excellent moisture barrier characteristics and impact relaxation characteristics, in the organic light emitting diode display device 400 according to the fourth embodiment of the present invention, the light emitting diode D, Is minimized.

That is, as described in FIG. 3, since the hydrogen of the hydroxyl group in the liquid phase moisture absorber has a positive electronegativity (? ⁺ ) And the oxygen of the water molecule has a negative electronegativity (? ^- ), the hydroxyl group of glycerin The oxygen of the water molecule makes a strong hydrogen bond.

Therefore, permeation of moisture by the barrier film 440 is prevented.

Since the organic layer 420 has a small modulus value by the liquid moisture absorbent 426 filling the empty space 424 of the polymer 422, the external impact is absorbed by the barrier film 440. Therefore, direct penetration of moisture and damage of the barrier film 440 due to an external impact are prevented, so that the damage of the light emitting diode D can be minimized.

Accordingly, it is possible to provide a high-quality, long-life organic light emitting diode display device 400 that does not deteriorate the display quality and the lifetime of the light emitting diode D due to moisture damage.

- Fifth Embodiment -

9A and 9B are schematic cross-sectional views illustrating a manufacturing process of a barrier film according to a fifth embodiment of the present invention.

As shown in FIG. 9A, an organic material is coated on the base 501 to form an organic material layer 510.

The base 501 may be a glass substrate or a plastic substrate. In addition, when the barrier film is used in an organic light emitting diode display device, the base 501 may be an inorganic layer constituting the second electrode or the encapsulation film of the light emitting diode.

The organic material includes a monomer 512, a liquid moisture absorbent 514, a photoinitiator (not shown), and a solvent (not shown). For example, based on the solvent, the monomer 512 has a weight ratio of about 30-50%, the liquid-phase moisture absorber 514 has a weight ratio of about 20-40%, the photoinitiator is about 0.1-1 % ≪ / RTI > by weight. The weight ratio of the monomer (512) is larger than the weight ratio of the liquid moisture absorber (514).

The organic material layer 510 is formed by a coating process such as ink-jet printing, silk-screen printing, roll printing, or nozzle printing.

When a barrier film is used in an organic light emitting diode display, the coating process of the organic material layer 510 may be performed in a nitrogen atmosphere to prevent damage to the light emitting diode.

Next, as shown in FIG. 9B, a barrier film 520 including the polymer 522 and the droplet-shaped liquid-phase moisture absorber 526 is formed by irradiating UV onto the organic material layer (510 in FIG. 9A) do. Further, the organic material layer 510 is heated to remove the solvent.

When UV is irradiated to the organic material layer 510, the monomer (512 in FIG. 9A) is cured, and a polymerization reaction occurs to form a polymer 522. At this time, the liquid moisture absorbent 526 aggregates and the liquid moisture absorbent 526 forms a droplet shape in the empty space 524 in the polymer 524. That is, the polymerization reaction rate of the monomer (512) is higher than the aggregation rate of the liquid moisture absorbent (526), and the liquid moisture absorbent (526) is introduced into the empty space (524) formed between the polymer (522) ). In other words, the liquid moisture absorbent 526 in the barrier film 520 has an increased droplet size than the liquid moisture absorbent 514 in the coated organic material.

The liquid moisture absorbent 526 has a first size (first diameter D1) in the upper region (UV irradiation direction region) and a second size (second diameter D2) larger than the first size D1 in the lower region, Lt; / RTI > For example, the second size D2 may be 400 nm or less, and the first size D1 may be 200 nm or less.

That is, since the polymeric material 522 is formed by UV irradiation, the liquid absorbent 526 is agglomerated, and the polymerization reaction occurs rapidly in the upper region where the UV irradiation amount is relatively large, so that the size of the void 524 in the upper region is reduced .

The size of the hollow space 524, that is, the size of the liquid moisture absorbent 526 may be inversely proportional to the UV intensity. That is, as the UV intensity increases, the polymerization reaction rate of the monomer 512 increases more than the coagulation speed of the liquid moisture absorber 526, so that the size of the liquid moisture absorber 526 decreases as the UV intensity increases.

The size of the liquid moisture absorber 526 may be proportional to the process temperature. That is, as the process temperature increases, the coagulation speed of the liquid moisture absorber 526 increases and the droplet size of the liquid moisture absorber 526 increases.

When a barrier film is used in an organic light emitting diode display, the UV irradiation process may proceed in a nitrogen atmosphere to prevent damage to the light emitting diode.

On the other hand, if a sufficient UV irradiation process is performed on the organic material layer 510, the liquid moisture absorbent 526 may have a uniform size in the barrier film 520.

In the case of the barrier film 300 shown in FIG. 7, after the first inorganic layer 320 is deposited, the steps of FIGS. 9A and 9B are performed, and then the second inorganic layer 330 is deposited to form a barrier film 300) can be produced.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It can be understood that

100, 300, 220, 440, 520: barrier film
Organic Light Emitting Diode Display Device: 200, 400
110, 222, 312, 422, 522: polymer
120, 224, 314, 424, 524:
130, 226, 316, 426, 526: liquid moisture absorber D: light emitting diode

Claims (12)

A first layer comprising a polymer having an empty space and a liquid absorbent in the empty space;
≪ / RTI >
The method according to claim 1,
Further comprising a second layer and a third layer, each layer being formed on the lower and upper sides of the first layer and made of an inorganic material.
The method according to claim 1,
Wherein the liquid humidifying agent has a hydroxyl group.
The method according to claim 1,
Wherein the liquid humidifying agent is glycerin.
The method according to claim 1,
Wherein a size of the liquid moisture absorber is 400 nm or less.
The method according to claim 1,
Wherein the liquid absorbent has a size of 400 to 700 nm and the refractive index difference between the polymer and the liquid absorbent is 0.01 or less.
The method according to claim 1,
Wherein the liquid humidifying agent has a first size in the first region and a second size in the second region larger than the first size.
Claims [1]
A light emitting diode located on the substrate;
The barrier film according to any one of claims 1 to 7, which covers the light emitting diode
And an organic light emitting diode (OLED) display device.
Coating an organic material including a monomer, a liquid-phase moisture absorber, and a photoinitiator to form an organic material layer;
Wherein the organic material layer is irradiated with UV to polymerize the monomer and aggregate the liquid moisture absorber
≪ / RTI >
10. The method of claim 9,
Wherein the size of the coagulated liquid moisture absorber is inversely proportional to the intensity of the UV.
10. The method of claim 9,
Wherein the size of the coagulated liquid-phase moisture absorber is proportional to the process temperature of the UV irradiation step.
10. The method of claim 9,
Wherein the liquid humidifying agent has a first size in the first region and a second size in the second region larger than the first size.

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