CN101080121A - An organic EL part and its making method - Google Patents

Abstract

The invention relates to a packaging structure of an organic electroluminescent device and a preparation method thereof. An organic electroluminescent device includes a packaging structure, which has a flat packaging cover, and its material is one of glass, polymer, metal or alloy materials and composite film materials. The planar packaging cap of the present invention can be prepared by a roller extrusion method to cover the device. The present invention is especially suitable for large-sized or flexible OLEDs. Because there is no gas space in the packaging process, the device can be made thinner, and the resulting deformation of the packaging cover can be avoided, thereby avoiding defects that cause gas leakage and damage to the cathode. , the preparation process can adopt assembly line operation, the production rhythm is continuous, fast and stable, and the production cost is reduced.

Description

A kind of organic electroluminescence device and preparation method thereof

technical field

The invention relates to a packaging structure of an organic electroluminescence device and a preparation method thereof, belonging to the technical field of organic electroluminescence.

Background technique

Today, with the development of multimedia technology and the advent of the information society, the requirements for the performance of flat panel displays are getting higher and higher. In recent years, three new display technologies have emerged: plasma display, field emission display and organic electroluminescent display (hereinafter referred to as OLED), all of which have made up for the shortcomings of cathode ray tubes and liquid crystal displays to a certain extent. Among them, organic electroluminescent displays have a series of advantages such as self-illumination, low-voltage DC drive, full curing, wide viewing angle, and rich colors. Low, its response speed can reach 1000 times that of LCD, but its manufacturing cost is lower than that of LCD with the same resolution. Therefore, organic electroluminescent displays have broad application prospects and are regarded as one of the extremely competitive future flat panel display technologies.

From the perspective of mass production technology, OLED products have not yet met the requirements of productization. The difficulties faced in realizing mass production of OLEDs mainly include the following aspects: (1) the life of OLEDs, (2) production technology and quality management Problems, (3) related technical problems (especially drive technology), among which, life is one of the biggest problems currently faced. It can be said that if the lifespan problem of OLEDs cannot be solved accordingly, the commercialization and practical application of a new generation of displays will be out of the question. At present, because the organic matter and the cathode in the device are very sensitive to water vapor and oxygen, that is to say, the lifetime of the OLED largely depends on the packaging effect of the device. A large number of studies have shown that water vapor and oxygen are the main reasons for the failure of OLEDs, and active metals as OLED cathodes are easy to react with water vapor and oxygen. We can make a simple estimate, the atomic weight of Mg is 24, and the density is 1.74g/cm ³ , if the thickness of the metal cathode Mg layer in the OLED is 50nm, the amount of metal Mg contained in the device is 3.6×10 ^-7 mol /cm ² , only about 6.4×10 ^-6 g of water is needed to completely react with it. To make Mg completely destroyed within one year, the encapsulation layer must have a water permeability of less than 1.5×10 ^-4 g/m ² /day. In fact, as long as 10% of the cathode in the device is oxidized, the non-luminescent region formed is very obvious (if the oxidation of the cathode occurs at the interface between the metal and the organic matter, even if the damaged cathode is only 5 Ȧ, the device may fail) It is generally believed that, ignoring the destructive effect of water and oxygen on the organic layer, the water-oxygen transmission rate of the encapsulation layer required by OLED should be less than 10 ^-5 g/m ² /day (Burrows PE, Graff GL, Gross ME, et al.Displays 22, 65 2001).

The existing OLED packaging method is a helmet-type packaging structure, that is, metal or glass is used as the packaging cover, and the adhesive is coated on the edge of the packaging cover to bond the packaging cover and the display screen together to form a relatively sealed space; In order to further absorb water vapor, it is also necessary to make a groove in the package cover, and fill the dry powder or dry flakes into the groove of the package cover. This kind of packaging method can well solve the damage of water and oxygen to OLED devices, but because the whole display screen is made of two thick glass or metal, OLED loses its light and thin advantages; in addition, because there is a Groove, the center of the package cover must have collapse and deformation. When preparing a large-size display, this collapse is more obvious, and the center of the package cover will even rub against the pixels of the display, destroying the display; The change of the gas pressure in the tank creates a pressure difference with the atmosphere, which leads to cracks in the encapsulation glue and damages the encapsulation effect. At the same time, this packaging method cannot be used for flexible displays and is not suitable for soft screens, because when the soft screen device is bent, the bonded packaging sheet may rub and damage the metal layer. Today, as a fully cured display device (whether it is a small molecule or a polymer), OLED's greatest advantage lies in the ability to prepare flexible display devices. Flexible organic electroluminescent devices refer to organic electroluminescent devices that use flexible materials as substrates. Luminescent devices, due to the characteristics of flexible substrates, endow such devices with unique application prospects, such as flexible display devices, flexible electronic newspapers, wallpaper TVs, wearable displays, etc.

In view of the above situation, the thin film encapsulation technology is being gradually developed and perfected, which is represented by Vitex's organic-inorganic composite thin film encapsulation technology. Its technology is characterized by first using organic materials to form a flat plane on the back of the device, and then forming a dense inorganic film on the plane to achieve the ability to block water and oxygen. Because a single inorganic film layer cannot obtain a good barrier effect , the encapsulation layer needs to be prepared into a multi-layer alternating structure. However, to prepare multiple cycles of organic polymers and inorganic ceramic materials, the process and equipment are very complicated, especially for ceramic materials, which are generally prepared by magnetron sputtering, plasma-enhanced chemical vapor deposition and other methods. Higher, it is easy to damage the organic layer or metal electrode of the OLED device, and when the object is bent, the material with poor bending ability (such as ceramic material) is easy to fall off, and follows the mechanism of "tunneling-delamination-bulge-fracture" , affecting the lifetime and mechanical properties of the device. Therefore, in the actual production application of this technology, there are disadvantages such as preparation process, complicated equipment, increased process difficulty, slow production rhythm, and high preparation cost.

Contents of the invention

The present invention focuses on the problems existing in the above-mentioned thin-film packaging technology, and proposes a new packaging structure and packaging method, which is especially suitable for large-size OLEDs and flexible OLEDs, so as to greatly improve the life of devices prepared by using thin-film packaging technology. Simultaneously, the preparation process is simplified and the production cost is reduced.

The invention proposes an organic electroluminescence device, which includes a substrate, an anode, a cathode and an organic functional layer between the two electrodes, and also includes a package structure with a planar package cover.

The encapsulation structure is located on the cathode side of the device, and is bonded to the device by encapsulation glue.

The material of the planar packaging cover of the present invention is glass, polymer, metal or alloy material and composite film material thereof. The preferred material is one of polyester (PET), polycarbonate (PC), polyethersulfone (PES), polyarylethernitrile (PEN), aluminum foil, steel foil, TiN/steel foil, PET/aluminum foil one of the films.

The encapsulating glue in the present invention is selected from one of UV glue, thermosetting glue and AB glue.

The encapsulation glue can also be doped with dry hygroscopic material. The dry hygroscopic material is at least one selected from alkali metals, alkaline earth metals, metal oxides, halides, sulfates, perchlorates, zeolites, and metal alcoholates with long-chain hydrocarbons.

A layer of protective film is also included between the encapsulation glue and the device in the encapsulation structure, and its material is selected from at least one of organic small molecule materials, inorganic materials or metal materials, preferably selected from AlQ, CuPc, SiOx, AlOx, SiNxOy, TiN One of.

There is also a dry layer between the flat package cover and the device in the package structure, and its material is selected from alkali metals, alkaline earth metals, metal oxides, halides, sulfates, perchlorates, zeolites, long-chain hydrocarbons metal alkoxides.

There is also a water and oxygen barrier layer between the planar package cover and the device in the package structure, and its material is selected from SiOx, AlOx, SiNxOy, TiN, polymethyl methacrylate, polyethyl methacrylate, epoxy resin , acrylic resin, one of UV curing glue and its composite structure.

The substrate of the organic electroluminescence device of the present invention can be flexible, and its material is selected from plastics, metal foil or ultra-thin glass.

The present invention also provides a method for encapsulating structures in organic electroluminescent devices. When the planar encapsulation cover is made of flexible materials, the encapsulation process includes: device delivery, encapsulation glue deposition, planar encapsulation cover transport, and planar encapsulation cover covering the device 1. The encapsulation glue is cured, which is characterized in that the planar encapsulation cover is covered on the device by a roller extrusion method.

The conveying of the planar packaging cap in the packaging method of the organic electroluminescent device in the present invention is roller conveying.

The method for conveying the device in the packaging method of the organic electroluminescence device of the present invention is selected from one of conveyor belt conveyance and roller-roller conveyance.

The encapsulation glue deposition described in the packaging method of the organic electroluminescent device of the present invention is deposited by a printing method, and the deposition process is carried out during the device delivery process.

Advantages of the technical solution of the present invention: the packaging cover is a flat packaging cover, and there is no gas space in the packaging process, which avoids the deformation of the packaging cover caused by this, and then causes the defects of gas leakage and destruction of the cathode, and can make the device thinner; packaging The process can adopt assembly line operation, and the production rhythm is continuous, fast and stable, which is especially suitable for the preparation of large-size screens and large-scale production.

Description of drawings

FIG. 1 is a schematic diagram of a device packaging method in Embodiment 4 of the present invention.

Detailed ways

(1) Preparation method of organic light-emitting device OLED:

Prepare the anode, organic functional layer and cathode sequentially on the substrate:

Substrate transparent substrate, which can be glass or flexible substrate, and the flexible substrate is made of polyester, polyimide compound, metal foil or ultra-thin glass;

The anode layer can be made of inorganic materials or organic conductive polymers. Inorganic materials are generally metal oxides such as ITO, zinc oxide, and tin zinc oxide, or metals with high work functions such as gold, copper, and silver. The optimal choice is ITO, organic The conductive polymer is preferably a material in polythiophene/sodium polyvinylbenzene sulfonate (hereinafter referred to as PEDOT:PSS), polyaniline (hereinafter referred to as PANI);

The cathode layer generally adopts metals with lower work functions such as lithium, magnesium, calcium, strontium, aluminum, indium, or their alloys with copper, gold, and silver, or an electrode layer formed alternately between metals and metal fluorides. The present invention preferably sequentially Mg:Ag alloy layer, Ag layer and successive LiF layer, Al layer;

The organic functional layer includes a light-emitting layer, and may also include functional layers such as an electron transport layer and a hole transport layer.

The light-emitting layer can be made of small molecule materials or polymer materials; the material of the light-emitting layer can be fluorescent materials, such as metal-organic complexes (such as Alq ₃ , Gaq ₃ , Al(Saph-q) or Ga(Saph-q)) Such compounds, the small molecule material can be doped with dyes, the doping concentration is 0.01wt% ~ 20wt% of the small molecule material, the dyes are generally aromatic condensed rings (such as rubrene), coumarins (such as DMQA, C545T ) or bispyran (such as DCJTB, DCM) compounds, the light-emitting layer material can also use phosphorescent materials, wherein carbazole derivatives such as CBP, polyvinylcarbazole (PVK) are the main materials, the main material Can be doped with phosphorescent dyes, such as tris(2-phenylpyridine) iridium (Ir(ppy) ₃ ), bis(2-phenylpyridine)(acetylacetonate) iridium (Ir(ppy) ₂ (acac)), octa Platinum ethyl porphyrin (PtOEP), etc.

Electron transport layer, the materials used are generally small molecule electron transport materials, which can be metal-organic complexes (such as Alq ₃ , Gaq ₃ , Al(Saph-q), BAlq or Ga(Saph-q)), aromatic fused rings ( Such as pentacene, perylene) or o-phenanthroline (such as Bphen, BCP) compounds.

For the hole transport layer, the materials used are generally low molecular materials of aromatic amines and dendrimers, such as N,N'-di-(1-naphthyl)-N,N'-diphenyl-1,1- Biphenyl-4,4-diamine (NPB), N,N'-diphenyl-N,N'-bis(m-methylphenyl)-1,1'-biphenyl-4,4' - Diamines (TPD) and the like.

The specific preparation method is to firstly clean the substrate pre-engraved with the anode, then sequentially vapor-deposit the hole transport layer material, the light-emitting layer material and the electron transport layer material on it, and finally prepare the cathode layer by vapor deposition.

(2) The preparation method of the packaging structure of the organic light-emitting device proposed by the present invention:

The material of the flat package cover can be glass, polymer, metal or alloy material and composite film material thereof, preferably polyester (PET), polycarbonate (PC), polyether sulfone (PES), polyarylether nitrile (PEN ), one of aluminum foil, steel foil, TiN/steel foil, PET/aluminum foil.

The packaging glue is selected from UV glue, heat curing glue or AB glue. The thickness of the packaging glue is about 10 μm˜500 μm.

The encapsulation glue can also be mixed with dry hygroscopic material. The dry hygroscopic material is at least one selected from alkali metals, alkaline earth metals, metal oxides, halides, sulfates, perchlorates, zeolites, and metal alcoholates with long-chain hydrocarbons. The volume percentage of the desiccant in the packaging glue is 10%-60%.

A layer of protective film may also be included between the encapsulant and the device, and its material is selected from at least one of organic small molecule materials, inorganic materials or metal materials, preferably selected from one of AlQ, CuPc, SiOx, AlOx, SiNxOy, TiN kind.

A dry layer may also be included between the planar package lid and the device, the material of which is selected from alkali metals, alkaline earth metals, metal oxides, halides, sulfates, perchlorates, zeolites, metal alcoholates with long chain hydrocarbons thing.

A layer of water and oxygen barrier layer can also be included between the planar package cover and the device, and its material is selected from SiOx, AlOx, SiNxOy, TiN, polymethyl methacrylate, polyethyl methacrylate, epoxy resin, acrylate , one of UV curing glue and its composite structure.

When preparing the packaging structure of the present invention, the following two methods can be used:

(2-1) Firstly, the encapsulating glue is deposited on the cathode layer on the back of the OLED device by wet film-making methods such as spin coating and printing, and the planar encapsulating cover is tightly pasted on the encapsulating glue.

(2-2) If the flat packaging cover is made of flexible material, the schematic diagram of the packaging process is shown in Figure 1. The substrate is conveyed by means of a conveyor belt. If the substrate is a soft substrate, it can be conveyed by a roller-roller method. During the process, the encapsulation film is deposited by printing method, covering the side surface of the substrate with the encapsulation, the encapsulation cover is conveyed by roller-roller method, and the encapsulation cover is covered on the substrate by the roller extrusion method, and finally the encapsulation glue is cured by UV light irradiation . The use of roller technology can effectively squeeze out the air bubbles in the encapsulant, and is especially suitable for large-scale production.

Example 1

(1) Prepare anode, organic functional layer and cathode on the substrate:

(1-1) Cleaning of pre-engraved ITO glass substrates: Use hot detergent ultrasonic and deionized water ultrasonic methods to clean the transparent conductive substrate ITO glass, after cleaning, place it under an infrared lamp to dry, and then The dried ITO substrate is pretreated by ultraviolet ozone cleaning and low-energy oxygen ion beam bombardment. The ITO film on the conductive substrate is used as the anode layer of the device. The square resistance of the ITO film is 50Ω and the film thickness is 150nm;

(1-2) Preparation of organic light-emitting layer: place the above-mentioned cleaned and dried ITO glass in a vacuum chamber, vacuumize to 1×10 ^-3 Pa, and then vapor-deposit an empty layer on the above-mentioned ITO film. The hole transport material NPB, the evaporation rate of the material film is 0.5nm/s, and the film thickness is 50nm; a layer of organic light-emitting material, 8-hydroxyquinoline aluminum Alq, is evaporated on the hole transport material, and the evaporation rate of the material film is 0.5nm/s, film thickness is 50nm;

(1-3) Preparation of the cathode: keep the pressure in the above vacuum chamber constant, sequentially vapor-deposit Mg on the above electron transport layer, and an Ag alloy layer as the cathode layer of the device, with a film thickness of 8nm. On top of the MgAg alloy layer, a 15 nm Ag layer was vapor-deposited. The alloy layer is doped by dual-source evaporation method;

(2) The packaging structure of the prepared device:

(2-1) Pass the above-mentioned device into a glove box, and prepare a layer of polyethyl methacrylate on the surface of the device by printing method, with a thickness of 100 μm;

(2-2) The glass is pressed on the above-mentioned device, and the UV light is irradiated and cured so that the substrate and the encapsulation sheet are integrated.

Example 2

(1) Prepare anode, organic functional layer and cathode on the substrate:

(1-1) Cleaning of pre-engraved ITO glass substrates: Use hot detergent ultrasonic and deionized water ultrasonic methods to clean the transparent conductive substrate ITO glass, after cleaning, place it under an infrared lamp to dry, and then The dried ITO substrate is pretreated by ultraviolet ozone cleaning and low-energy oxygen ion beam bombardment. The ITO film on the conductive substrate is used as the anode layer of the device. The square resistance of the ITO film is 50Ω and the film thickness is 150nm;

(1-2) Preparation of organic light-emitting layer: place the above-mentioned cleaned and dried ITO glass in a vacuum chamber, vacuumize to 1×10 ^-3 Pa, and then vapor-deposit an empty layer on the above-mentioned ITO film. The hole transport material NPB, the evaporation rate of the material film is 0.5nm/s, and the film thickness is 50nm; a layer of organic light-emitting material, 8-hydroxyquinoline aluminum Alq, is evaporated on the hole transport material, and the evaporation rate of the material film is 0.5nm/s, film thickness is 50nm;

(1-3) Preparation of the cathode: keep the pressure in the above vacuum chamber constant, sequentially vapor-deposit Mg on the above electron transport layer, and an Ag alloy layer as the cathode layer of the device, with a film thickness of 8nm. On top of the MgAg alloy layer, a 15 nm Ag layer was vapor-deposited. The alloy layer is doped by dual-source evaporation method;

(2) The packaging structure of the prepared device:

(2-1) Sputtering metal Al in a vacuum chamber, while feeding high-purity oxygen, the air pressure in the chamber is 10 ^-2 Pa, depositing Al ₂ O ₃ on the device as described in (1), The deposition rate is 0.5nm/s, and the film thickness is 80nm;

(2-2) Pass the above-mentioned device into the glove box, and prepare A glue and B glue of AB glue on the surface of the device and the TiN/steel foil of the planar packaging board by printing method, both of which have a thickness of 100 μm;

(2-3) Press the TiN/steel foil on the above-mentioned device, and after standing for 1 minute, the substrate and the packaging sheet form a whole.

Example 3

(1) Prepare anode, organic functional layer and cathode on the substrate:

(1-1) Cleaning of pre-engraved ITO glass substrates: Use hot detergent ultrasonic and deionized water ultrasonic methods to clean the transparent conductive substrate ITO glass, after cleaning, place it under an infrared lamp to dry, and then The dried ITO substrate is pretreated by ultraviolet ozone cleaning and low-energy oxygen ion beam bombardment. The ITO film on the conductive substrate is used as the anode layer of the device. The square resistance of the ITO film is 50Ω and the film thickness is 150nm;

(1-2) Preparation of organic light-emitting layer: place the above-mentioned cleaned and dried ITO glass in a vacuum chamber, vacuumize to 1×10 ^-3 Pa, and then vapor-deposit an empty layer on the above-mentioned ITO film. The hole transport material NPB, the evaporation rate of the material film is 0.5nm/s, and the film thickness is 50nm; a layer of organic light-emitting material, 8-hydroxyquinoline aluminum Alq, is evaporated on the hole transport material, and the evaporation rate of the material film is 0.5nm/s, film thickness is 50nm;

(1-3) Preparation of the cathode: keep the pressure in the above vacuum chamber constant, sequentially vapor-deposit Mg on the above electron transport layer, and an Ag alloy layer as the cathode layer of the device, with a film thickness of 8nm. On top of the MgAg alloy layer, a 15 nm Ag layer was vapor-deposited. The alloy layer is doped by dual-source evaporation method;

(2) The packaging structure of the prepared device:

(2-1) Keep the pressure of the vacuum chamber constant, sputter the electrodeless material SiOxNy on the device as described in (1), the deposition rate is 0.5nm/s, and the film thickness is 120nm;

(2-2) Keeping the pressure of the vacuum chamber constant, vapor-deposit a layer of epoxy resin glue on the SiOxNy with a thickness of 20 μm;

(2-3) Press the PET substrate on the above device, the surface of the PET substrate has a composite film formed by SiO2 and Al2O3, and irradiate with UV light, so that the substrate and the packaging sheet are integrated.

Example 4

(1) Prepare anode, organic functional layer and cathode on the substrate:

(1-1) Cleaning of pre-engraved ITO glass substrates: Use hot detergent ultrasonic and deionized water ultrasonic methods to clean the transparent conductive substrate ITO glass. The size of the substrate is 370cm×470cm. After cleaning, place it Dry in a vacuum oven, and then pre-treat the dried ITO substrate with ultraviolet ozone cleaning and low-energy oxygen ion beam bombardment. The ITO film on the conductive substrate is used as the anode layer of the device, and the square resistance of the ITO film is 50Ω. The film thickness is 150nm;

(1-2) Preparation of organic light-emitting layer: place the above-mentioned cleaned and dried ITO glass in a vacuum chamber, evacuate to 1×10 ^-4 Pa, and then evaporate a layer of empty glass on the above-mentioned ITO film. The hole transport material NPB, the evaporation rate of the material film is 0.5nm/s, and the film thickness is 50nm; a layer of organic light-emitting material, 8-hydroxyquinoline aluminum Alq, is evaporated on the hole transport material, and the evaporation rate of the material film is 0.5nm/s, film thickness is 50nm;

(1-3) Preparation of the cathode: keep the pressure in the above vacuum chamber constant, sequentially vapor-deposit Mg on the above electron transport layer, and an Ag alloy layer as the cathode layer of the device, with a film thickness of 8nm. On top of the MgAg alloy layer, a 15 nm Ag layer was vapor-deposited. The alloy layer is doped by dual-source evaporation method;

(2) The packaging structure of the prepared device:

(2-1) Keeping the pressure of the vacuum chamber constant, vapor-deposit the organic material CuPc on the device as described in (1), the deposition rate is 0.5nm/s, and the film thickness is 300nm;

(2-2) Pass the above-mentioned device into a glove box, place it on a conveyor belt, transport the substrate at a speed of 10cm/min, and prepare a layer of epoxy resin glue on the surface of the device by printing, with a thickness of 300 μm;

(2-3) Put the Al foil on a roller, and the roller rolls at a linear speed of 10 cm/min to press the Al foil on the substrate. Place it under the condition of 80° C. for 1 hour, and the packaging board and the substrate form a whole.

Example 5

(1) Prepare anode, organic functional layer and cathode on the substrate:

(1-1) Cleaning of PET substrates pre-engraved with ITO: use hot detergent ultrasonic and deionized water ultrasonic methods to clean the transparent conductive substrate covered with water oxygen barrier layer and ITO PET substrate, after cleaning It is placed under an infrared lamp to dry, and then the dried ITO substrate is pretreated by ultraviolet ozone cleaning and low-energy oxygen ion beam bombardment, wherein the ITO film on the conductive substrate is used as the anode layer of the device, and the square resistance of the ITO film is 50Ω, film thickness is 150nm;

(1-2) Preparation of organic light-emitting layer: place the above-mentioned cleaned and dried ITO substrate in a vacuum chamber, evacuate to 1×10 ^-3 Pa, and then vapor-deposit a layer on the above-mentioned ITO film The hole transport material NPB, the evaporation rate of the material film is 0.5nm/s, and the film thickness is 50nm; a layer of organic light-emitting material, 8-hydroxyquinoline aluminum Alq, is evaporated on the hole transport material, and the evaporation of the material film is The rate is 0.5nm/s, and the film thickness is 50nm;

(1-3) Preparation of the cathode: keep the pressure in the above vacuum chamber constant, sequentially vapor-deposit Mg on the above electron transport layer, and an Ag alloy layer as the cathode layer of the device, with a film thickness of 8nm. On top of the MgAg alloy layer, a 15 nm Ag layer was vapor-deposited. The alloy layer is doped by dual-source evaporation method;

(2) The packaging structure of the prepared device:

(2-1) Keeping the pressure of the vacuum chamber constant, prepare a layer of Al ₂ O ₃ film by sputtering method on the device as described in (1), the deposition rate is 0.5nm/s, and the film thickness is 120nm;

(2-2) Pass the above-mentioned device into a glove box, and prepare a layer of epoxy resin glue on the surface of the device by printing method. CaO particles with a diameter of 200 nm are mixed in the epoxy resin glue, and the thickness is 200 μm;

(2-3) Press the PC substrate on the above-mentioned device, the surface of the PC substrate has a composite film formed by SiO2 and Al2O3, and irradiate with UV light, so that the substrate and the encapsulation sheet are integrated.

Example 6

(1) Prepare anode, organic functional layer and cathode on the substrate:

(1-1) Cleaning of PET substrates pre-engraved with ITO: use hot detergent ultrasonic and deionized water ultrasonic methods to clean the transparent conductive substrate covered with water oxygen barrier layer and ITO PET substrate, after cleaning It is placed under an infrared lamp to dry, and then the dried ITO substrate is pretreated by ultraviolet ozone cleaning and low-energy oxygen ion beam bombardment, wherein the ITO film on the conductive substrate is used as the anode layer of the device, and the square resistance of the ITO film is 50Ω, film thickness is 150nm;

(1-2) Preparation of organic light-emitting layer: place the above-mentioned cleaned and dried ITO substrate in a vacuum chamber, evacuate to 1×10 ^-3 Pa, and then vapor-deposit a layer on the above-mentioned ITO film The hole transport material NPB, the evaporation rate of the material film is 0.5nm/s, and the film thickness is 50nm; a layer of organic light-emitting material, 8-hydroxyquinoline aluminum Alq, is evaporated on the hole transport material, and the evaporation of the material film is The rate is 0.5nm/s, and the film thickness is 50mn;

(1-3) Preparation of the cathode: keep the pressure in the above vacuum chamber constant, sequentially vapor-deposit Mg on the above electron transport layer, and an Ag alloy layer as the cathode layer of the device, with a film thickness of 8nm. On top of the MgAg alloy layer, a 15 nm Ag layer was vapor-deposited. The alloy layer is doped by dual-source evaporation method;

(2) The packaging structure of the prepared device:

(2-1) Keep the pressure of the vacuum chamber constant, prepare a layer of TiN film by sputtering method on the device as described in (1), the deposition rate is 0.5nm/s, and the film thickness is 80nm;

(2-2) Pass the above-mentioned device into the glove box, place it on a roller, and roll it at a linear speed of 10 cm/min. A layer of epoxy resin glue is prepared on the surface of the device by printing. The epoxy resin glue is mixed with a diameter 200nm _CaCl2 particles with a thickness of 200μm;

(2-3) Place the PEN/Al packaging sheet on the roller, roll it at a linear speed of 10cm/min, press the PEN/Al packaging sheet on the device, and place it at 80°C for 1 hour to cure the epoxy resin glue , so that the substrate and the package form a whole.

Example 7

(1) Prepare anode, organic functional layer and cathode on the substrate:

(1-1) Cleaning of pre-engraved ITO glass substrates: Use hot detergent ultrasonic and deionized water ultrasonic methods to clean the transparent conductive substrate ITO glass or the PET substrate covered with water and oxygen barrier layer. It is placed under an infrared lamp to dry, and then the dried ITO substrate is pretreated by ultraviolet ozone cleaning and low-energy oxygen ion beam bombardment, wherein the ITO film on the conductive substrate is used as the anode layer of the device, and the square resistance of the ITO film is 50Ω, the film thickness is 150nm;

(1-2) Preparation of organic light-emitting layer: place the above-mentioned cleaned and dried ITO glass in a vacuum chamber, vacuumize to 1×10 ^-3 Pa, and then vapor-deposit an empty layer on the above-mentioned ITO film. The hole transport material NPB, the evaporation rate of the material film is 0.5nm/s, and the film thickness is 50nm; a layer of organic light-emitting material, 8-hydroxyquinoline aluminum Alq, is evaporated on the hole transport material, and the evaporation rate of the material film is 0.5nm/s, film thickness is 50nm;

(1-3) Preparation of the cathode: keep the pressure in the above vacuum chamber constant, sequentially vapor-deposit Mg on the above electron transport layer, and an Ag alloy layer as the cathode layer of the device, with a film thickness of 8nm. On top of the MgAg alloy layer, a 15 nm Ag layer was vapor-deposited. The alloy layer is doped by dual-source evaporation method;

(2) The packaging structure of the prepared device:

(2-1) Keeping the pressure in the vacuum chamber constant, evaporate Alq on the device prepared by the method described in (1), the deposition rate is 0.5nm/s, and the film thickness is 500nm;

(2-2) Pass the above-mentioned device into a glove box, and prepare a layer of polyethyl methacrylate on the surface of the device by printing method, with a thickness of 100 μm;

(2-3) Apply a liquid molecular sieve desiccant on the surface of the packaging glass by spin coating, the rotation speed is 1000 rpm, and place it at 220°C for 2 hours, the solvent in the molecular sieve desiccant will completely evaporate and become solid.

(2-4) The glass coated with desiccant is pressed on the device, cured by UV light irradiation, and the substrate and the encapsulation sheet are formed as a whole.

Because the commonly used gas transmission rate detection equipment can only detect the transmission rate above 10 ^-2 g/m ² /day, and the transmission rate after packaging is below this range, the oxidation of active metal Ca is used to detect the impact of cycle number on packaging performance. Impact:

The above three embodiments and the Ca oxidation test results of the unpackaged device are shown in the following table:

The packaging structure is: glass substrate (or PET substrate)/Ca/encapsulation layer

Observe the time of complete oxidation of Ca with the naked eye in an environment with a temperature of 50°C and a humidity of 95%: Package structure Ca complete oxidation time/h Unencapsulated glass substrate 10.2 Example 1 603.1 Example 2 517.5 Example 3 452.8 Example 4 592.0 Example 7 713.3

Unpackaged PET substrate 8.0 Example 5 226.9 Example 6 135.6

Compared with the unencapsulated structure, the encapsulation structure of the present invention significantly improves the permeability of water and oxygen, so the device can be protected from external water and oxygen corrosion.

Although the present invention has been described in conjunction with preferred embodiments, the present invention is not limited to the above embodiments, especially the encapsulation layer of the present invention can be prepared on the cathode side of the device, or on the entire surface of the device. It should be understood that various modifications and improvements can be made by those skilled in the art under the guidance of the concept of the present invention, and the appended claims outline the scope of the present invention.

Claims (17)

1. an organic electroluminescence device comprises substrate, anode, negative electrode and the organic function layer between two electrodes, also comprises encapsulating structure, it is characterized in that, has the planar package lid in the described encapsulating structure.

2. organic electroluminescence device according to claim 1 is characterized in that, described encapsulating structure is positioned at negative electrode one side of device.

3. organic electroluminescence device according to claim 1 is characterized in that, the material of described planar package lid is glass, polymer, metal or alloy material and composite film material thereof.

4. organic electroluminescence device according to claim 3 is characterized in that, the material of described planar package lid is preferably a kind of in polyester (PET), polycarbonate (PC), polyether sulfone (PES), the poly (arylene ether nitrile) (PEN).A kind of in aluminium foil, steel foil, TiN/ steel foil sheet, the PET/ aluminium foil.

5. organic electroluminescence device according to claim 1 is characterized in that, described planar package lid is bonding by packaging plastic and device.

6. organic electroluminescence device according to claim 5 is characterized in that, described packaging plastic is selected from a kind of in UV glue, heat-curable glue, the AB glue.

7. organic electroluminescence device according to claim 5 is characterized in that, is doped with dry hygroscopic material in the described packaging plastic.

8. organic electroluminescence device according to claim 7, it is characterized in that described dry hygroscopic material is selected from alkali metal, alkaline-earth metal, metal oxide, halide, sulfate, perchlorate, zeolite, have at least a in the metal alcoholate of long-chain hydrocarbon.

9. organic electroluminescence device according to claim 5 is characterized in that, comprises also that between described packaging plastic and device layer protecting film, its material are selected from least a in organic small molecule material, inorganic material or the metal material.

10. organic electroluminescence device according to claim 9 is characterized in that, the material of described diaphragm is a kind of in AlQ, CuPc, SiOx, AlOx, SiNxOy, TiN preferably.

11. organic electroluminescence device according to claim 1, it is characterized in that, also comprise one deck drying layer between described planar package lid and the device, its material is selected from alkali metal, alkaline-earth metal, metal oxide, halide, sulfate, perchlorate, zeolite, has the metal alcoholate of long-chain hydrocarbon.

12. organic electroluminescence device according to claim 1, it is characterized in that, also comprise one deck water, oxygen barrier layer between described planar package lid and the device, its material is selected from a kind of and composite construction in SiOx, AlOx, SiNxOy, TiN, polymethyl methacrylate, polyethyl methacrylate, epoxy resin, acrylate, the UV curing glue.

13. organic electroluminescence device according to claim 1, the substrate that it is characterized in that described device is for flexible, and its material is selected from plastics, tinsel or ultra-thin glass.

14. method for preparing encapsulating structure in the described organic electroluminescence device of claim 1, when the planar package lid is flexible material, encapsulation process comprises: device transmits, packaging plastic deposits, the planar package lid transmits, the planar package lid covers on the device, packaging plastic solidifies, and it is characterized in that it is to cover on the device by the drum extrusion method that planar package is covered.

15. the method for packing of organic electroluminescence device according to claim 14 is characterized in that, it is that cylinder transmits that described planar package lid transmits.

16. the method for packing of organic electroluminescence device according to claim 14 is characterized in that, described device transfer approach be selected from that conveyer belt transmits and cylinder-cylinder transmission in a kind of.

17. the method for packing of organic electroluminescence device according to claim 15 is characterized in that, described packaging plastic deposition is that deposition process is carried out in the device transport process by the printing process deposition.

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