The present disclosure relates to the technical field of organic light-emitting diode (OLED) devices and in particular to an OLED device and a manufacturing method therefor.
Organic electroluminescent devices (OLED devices) have more advantages than other lighting methods (such as candles, halogen lamps and LED lamps), for example, have no ultraviolet, no infrared radiation, soft light, no glare, no flicker, rich spectrum and high color rendering quality, and can be used for general lighting, automotive lighting and display fields. Currently, a major bottleneck for OLED devices is the service life.
The traditional OLED device structure includes a substrate, an anode, an insulating layer, organic functional layers, a cathode, and an encapsulation structure. The substrate is usually an alkali-free glass (Glass). The anode is usually a transparent conductive oxide (such as indium tin oxide (ITO) and aluminum doped zinc oxide (AZO)). The insulating layer is generally photolithographic resin, such as phenolic resin or polymethyl methyl acrylate. The organic functional layers may include a hole injection layer (HIL), a hole transport layer (HTL), an light-emitting layer (EML), an electron transport layer (ETL), an electron injection layer (EIL), etc. The encapsulation layer may be a glass encapsulation cover and is adhered to the substrate through ultraviolet (UV) glue to protect the organic functional layers. The traditional device structure includes the following disadvantages:
Therefore, the present disclosure aims to solve the problem of poor service life and failure of a device caused by materials or structures in the existing art. For this reason, the present disclosure provides an OLED device and a manufacturing method therefor. A buffer layer is added on the substrate so that the metal ions in the glass can be prevented from penetrating into the device. At the same time, the added buffer layer can improve the dry etching undercut problem of the auxiliary electrode on the buffer layer to form a taper angle of 20° to 80° of the auxiliary electrode, which improves the encapsulation service life of the device. In addition, the inorganic compounds are selected as the pixel defining layer so that the volatile gas can be prevented from being released (outgassed) into the pixel, and thus the pixel is prevented from shrink, which improves the reliability of the OLED panel. Furthermore, the pixel defining layer provided on the first electrode layer and the auxiliary electrode is in direct contact with the buffer layer, forming a good surrounding structure for the effective pixel region and/or the pixel of the OLED, and reducing the erosion of the pixel region caused by particles or gases introduced during the process. At the same time, the pixel defining layer and/or the buffer layer located at the encapsulation region are patterned. The encapsulation layer on the OLED materials is in direct contact with the patterned pixel defining layer and/or buffer layer to further form a good stress relief structure, increasing the interface encapsulation effect. The intrusion of water and oxygen is reduced, and the encapsulation reliability is improved.
In order to achieve the above object, the present disclosure adopts the technical solutions described below.
An OLED device is provided and includes a substrate and an encapsulation layer, where the substrate and the encapsulation layer form a hermetic space in which a first electrode layer, serval auxiliary electrodes arranged at intervals and a pixel defining layer are arranged.
A buffer layer is provided between the first electrode layer/the serval auxiliary electrodes and a substrate the buffer layer is provided with the serval auxiliary electrodes, the first electrode layer covers the buffer layer and the serval auxiliary electrodes, the pixel defining layer completely covers the first electrode layer on the auxiliary electrode and is patterned with an aperture which exposes at least a part of the first electrode layer, and the pixel defining layer and the aperture are sequentially covered with an organic light emitting layer and a second electrode layer.
The substrate is divided with serval pixel regions distributed in an array and an encapsulation region surrounding all the pixel regions, an edge position of each of the serval pixel regions is surrounded by the pixel defining layer, and the serval auxiliary electrodes are distributed in at least one of a horizontal position or a vertical position of the pixel regions distributed in the array.
The first electrode layer and the serval auxiliary electrodes at the encapsulation region are removed by etching process so that the buffer layer is in direct contact with the pixel defining layer.
A continuous patterned structure is formed on the buffer layer located at the encapsulation region, and the encapsulation layer is in direct contact with the patterned structure of the buffer layer.
The patterned structure is at least one of serval groove structures or serval dam structures patterned on the buffer layer.
The first electrode layer located on one or two sides of each of the serval auxiliary electrodes is removed by etching process so that the pixel defining layer located in the one or two sides of the each of the serval auxiliary electrodes is in direct contact with the buffer layer.
A width of a region at which the first electrode layer located on one or two sides of the each of the serval auxiliary electrodes is in direct contact with the buffer layer is 1 μm to 1 cm.
The first electrode layer between two adjacent pixel regions distributed in the array is patterned with a short-circuit prevention structure layer in a direction perpendicular to the serval auxiliary electrodes, and the short-circuit prevention structure layer is electrically connected to the first electrode layer on the each of the serval auxiliary electrodes and one of the two adjacent pixel regions and forms a disconnect with another one of the two adjacent pixel regions; and the pixel defining layer located on two sides of the short-circuit prevention structure layer is in direct contact with the buffer layer.
A width of a region at which the pixel defining layer is in direct contact with the buffer layer located on one or two sides of the each of the serval auxiliary electrodes is 5 μm to 10 mm.
The each of the serval auxiliary electrodes is a combination of one or more of titanium (Ti), aluminum (Al), molybdenum (Mo), or copper (Cu).
A taper angle of the each of the serval auxiliary electrodes is 10° to 90°.
An etching selection ratio of a material with a low etching rate of each of the serval auxiliary electrodes to a material of the buffer layer is from 0.5 to 20; and the etching selection ratio of a material of the pixel defining layer to the material of the buffer layer is from 0.5 to 5.
Furthermore and preferably, etching selection ratio of the material of each of the serval auxiliary electrodes to the material of the buffer layer is from 5 to 7.
A thickness of the buffer layer is 10 nm to 3 μm.
A planarized auxiliary buffer layer is also provided on the buffer layer located between the serval auxiliary electrodes, and the each of the serval auxiliary electrodes is higher than the auxiliary buffer layer by 0 μm to 1 μm.
The pixel defining layer, the buffer layer and the encapsulation layer are made of same materials or different materials which are a combination of one or more of silicon nitride, silicon oxide, or silicon oxynitride.
The encapsulation layer has a thin film encapsulation structure, a cover plate is further provided on the encapsulation layer, and the cover plate is combined with the encapsulation layer through an encapsulation transition layer.
Alternatively, the encapsulation layer is an encapsulation cover, and the encapsulation cover is combined with the buffer layer of an encapsulation region on the substrate by a UV glue.
Meanwhile, the present disclosure also provides a manufacturing method of an OLED device. The method includes the steps described below.
In S1, a substrate is divided into a pixel region and an encapsulation region surrounding the pixel region, and a buffer layer is deposited on the substrate, where an auxiliary electrode layer is manufactured on the buffer layer which is etched to form serval auxiliary electrodes arranged at intervals, and a taper angle of each of the serval auxiliary electrodes is 10° to 90°.
In S2, a first electrode layer is manufactured on a basis of step S1, where the first electrode layer covers the buffer layer and the auxiliary electrode, and the first electrode layer located between the auxiliary electrode and the encapsulation region is removed by etching process in order to expose the buffer layer.
In S3, a pixel defining layer is deposited on a basis of step S2, where the pixel defining layer covers the first electrode layer and the buffer layer, and the pixel defining layer is etched to form an aperture, where a bottom of the aperture is the first electrode layer and the buffer layer.
In S4, an organic light-emitting layer and a second electrode layer are made by an evaporation method on a basis of step S3, where the organic light-emitting layer and the second electrode layer are sequentially formed on the pixel defining layer and the aperture.
In S5, an encapsulation layer is made on a basis of step S4, where the encapsulation layer covers the entire pixel region, and the encapsulation region surrounding the pixel region seals and protects the entire pixel region.
The step S2 is as follows: the first electrode layer is manufactured on the basis of the step S1, where the first electrode layer covers the buffer layer and the serval auxiliary electrodes, the first electrode layer located on one or two sides of each of the serval auxiliary electrodes is removed by etching process so as to expose the buffer layer, and etching is performed to form a short-circuit prevention structure layer.
The buffer layer located at the encapsulation region is formed with at least one of serval patterned groove structures or serval dam structures in the step S3, and the encapsulation layer is in direct contact with at least one of the serval patterned groove structures or the serval dam structures on the buffer layer in an encapsulating process of step S5.
The present disclosure has the beneficial effects described below compared with the existing art.
In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the existing art, the drawings that need to be used in the embodiments or the description of the existing art are described below. Apparently, the drawings in the following description are some embodiments of the present disclosure. For those of ordinary skill in the field, other drawings can be obtained based on these drawings without creative work.
The technical solutions of the present disclosure will be clearly and completely described below in conjunction with the drawings. Apparently, the described embodiments are part, not all, of the embodiments of the present disclosure. Based on the embodiments of the present disclosure, all other embodiments obtained by those of ordinary skill in the field without creative work shall fall within the scope of the present disclosure.
In the description of the present disclosure, it should be noted that the orientation or positional relationship indicated by terms “center”, “above”, “under”, “left”, “right”, “vertical”, “horizontal”, “inner”, “outer”, and the like are based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and thus it is not to be construed as a limitation of the present disclosure. In addition, the terms of “first”, “second”, and “third” are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
The present disclosure can be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure is thorough and complete, and the concept of the present disclosure is fully conveyed to those skilled in the art. The present disclosure is only defined by the claims. In the drawings, the sizes and relative sizes of layers and regions are exaggerated for clarity. It should be understood that when an element such as a layer, region, or substrate is referred to as being “formed on” or “disposed on” another element, the element may be directly disposed on another element, or there may be an intermediate element. In contrast, when an element is referred to as being “directly formed on” or “directly disposed on” another element, there is no intermediate element.
In addition, the technical features involved in the different embodiments of the present disclosure described below can be combined with each other as long as there is no conflict between them.
As shown in
The substrate 1 is divided with a number of pixel regions 11 and an encapsulation region surrounding all the pixel regions 11, an edge position of each pixel region 11 is surrounded by the pixel defining layer 12. The auxiliary electrodes are distributed in the horizontal position and/or vertical position of the pixel regions distributed in the array. The first electrode layer 2 and the auxiliary electrode 7 at the encapsulation region are removed by etching process so that the buffer layer is in direct contact with the pixel defining layer 12 located between the auxiliary electrode 7 and the encapsulation region. Preferably, the width of the region at which the pixel defining layer 12 is in direct contact with the buffer layer 6 is 5 μm to 10 mm.
In a preferred embodiment, as shown in
The auxiliary electrode 7 is a combination of one or more of titanium (Ti), aluminum (Al), molybdenum (Mo), or copper (Cu). For example, titanium aluminum titanium (TiAlTi), aluminum titanium (AlTi), aluminum molybdenum (AlMo), molybdenum aluminum molybdenum (MoAlMo), molybdenum (Mo), titanium (Ti), copper (Cu) and aluminum (Al). As shown in the
The etching selection ratio of a material with a low etch rate of the auxiliary electrode 7 to a material of the buffer layer 6 is from 0.5 to 20 and is preferably from 5 to 7. The Ti or Mo material in the auxiliary electrode has a low etch rate.
The etching selection ratio of a material of the pixel defining layer 12 to the material of the buffer layer 6 is from 0.5 to 5.
The thickness of the buffer layer 6 is 10 nm to 3 μm and is preferably 100 nm.
A planarized auxiliary buffer layer is also provided on the buffer layer 6 located between the auxiliary electrodes 7, and the auxiliary electrode 7 is higher than the auxiliary buffer layer by 0 μm to 1 μm.
The pixel defining layer 12, the buffer layer 6 and the encapsulation layer are made of the same materials or different materials which are a combination of one or more of silicon nitride, silicon oxide, or silicon oxynitride.
The encapsulation layer 10 is a glass encapsulation cover 5 provided with the UV glue 8. The glass encapsulation cover 5 is combined with the buffer layer 6 and/or the pixel defining layer 12 on the substrate 1 through the UV glue 8.
Of course, the encapsulation layer may also adopt a thin film encapsulation method, and the encapsulation layer 10 may be made by chemical vapor deposition. The organic light-emitting layer 3, the second electrode layer 4, and the encapsulation layer are sequentially covered from bottom to top on the pixel defining layer 12 and in the aperture. Meanwhile, the encapsulation layer at the encapsulation region is in direct contact with the buffer layer to form thin-film encapsulation. An encapsulation transition layer such as the UV glue or OCA glue is attached to the encapsulation layer, and then a cover plate is attached to the encapsulation transition layer for sealing. Here the cover plate may include glass, copper foil, aluminum foil, and the like.
In order to achieve a better encapsulation effect at the OLED encapsulation region, a continuous patterned structure is formed on the buffer layer 6 located at the encapsulation region, and the encapsulation layer 10 is in direct contact with the patterned structure formed on the buffer layer 6. As shown in
As shown in
In S1, a substrate 1 is divided into a pixel region 11 and an encapsulation region surrounding the pixel region 11, a buffer layer 6 is deposited on the pixel region, an auxiliary electrode layer 7 is manufactured on the buffer layer 6 which is etched to form a number of auxiliary electrodes 7 arranged at intervals, and the taper angle of the auxiliary electrode 7 is 10° to 90°.
In S2, a first electrode layer 2 is manufactured on the basis of step S1. The first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7. The first electrode layer 2 located between the auxiliary electrode 7 and the encapsulation region 9 is removed by etching process in order to expose the buffer layer 6.
In S3, a pixel defining layer 12 is deposited on the basis of step S2, where the pixel defining layer 12 covers the first electrode layer 2 and the buffer layer 6. The pixel defining layer 12 is etched to form an aperture of a trapezoidal structure. The bottom of the trapezoidal structure is the first electrode layer 2 and the buffer layer 6.
In S4, an organic light-emitting layer 3 and a second electrode layer 4 are made by an evaporation method on the basis of step S3, and the organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the aperture.
In S5, an encapsulation layer 10 is made on the basis of step S4, the encapsulation layer 10 covers the entire pixel region 11, and the encapsulation region 9 surrounding the pixel region 11 seals and protects the entire pixel region 11.
When the structure shown in
The materials and thickness of each layer are as described below.
Of course, in order to improve the encapsulation reliability of the panel, the thin film encapsulation method is used, such as inorganic layer/organic layer/inorganic layer. The inorganic layer can be deposited by chemical vapor deposition (CVD) so that thin film deposition is performed, and the organic layer can be printed by inkjet printing (IJP) so that thin film printing is performed. For example, SiO (1 μm)/IJP(8 μm)/SiO(1 μm) is used.
The present disclosure has the embodiments described below.
As shown in
The light-emitting region of the substrate 1 is provided with the buffer layer 6, and a number of auxiliary electrodes 7 arranged at intervals are provided on the buffer layer 6. A first electrode layer 2 covers the buffer layer 6 and the auxiliary electrodes 7. The first electrode layer 2 located between the auxiliary electrodes 7 and the encapsulation region is removed by etching process to expose the buffer layer 6. The width of the removed first electrode layer 2 is H=10 μm.
The pixel defining layer 12 completely covers the first electrode layer on the auxiliary electrode and is patterned with apertures which expose at least a part of the first electrode layer. The shape of the aperture is a trapezoidal structure. The bottom of the trapezoid is the first electrode layer 2. The organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the apertures. The buffer layer 6 is in direct contact with the pixel defining layer 12 since no first electrode layer exists on the buffer layer 6 located between the auxiliary electrode 7 and the encapsulation region 9.
The width H of the region at which the pixel defining layer 12 is in direct contact with the buffer layer 6 is 10 μm.
The auxiliary electrode 7 includes an Al material layer and a Ti material layer which are superimposed. The Ti material layer is located above the Al material layer. As shown in
The etching selection ratio of the material of the auxiliary electrode 7 to the material of the buffer layer 6 is from 0.5 to 20 and is preferably from 5 to 7.
The etching selection ratio of the material of the pixel defining layer 12 to the material of the buffer layer 6 is from 0.5 to 5.
The etching selection ratio refers to the ratio of the etch rate of different films under the same condition. That is, the etch rate of film A is Ea, the etch rate of film B under the same condition is Eb, and the etching selection ratio at this time is SA/B=Ea/Eb.
The pixel defining layer and the buffer layer are made of the same materials or different materials which are a combination of one or more of silicon nitride, silicon oxide, or silicon oxynitride.
As shown in
In S1, a substrate 1 is divided into a pixel region 11 and an encapsulation region surrounding the pixel region 11, a buffer layer 6 is deposited at the pixel region, an auxiliary electrode layer is manufactured on the buffer layer 6 which is etched to form a number of auxiliary electrodes 7 arranged at intervals, and the taper angle of the auxiliary electrode 7 is 20° to 80°.
In S2, a first electrode layer 2 is manufactured on the basis of step S1. The first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7. The first electrode layer 2 located between the auxiliary electrodes 7 and the encapsulation region is removed by etching process in order to expose the buffer layer 6.
In S3, a pixel defining layer 12 is deposited on the basis of step S2, where the pixel defining layer 12 covers the first electrode layer 2 and the buffer layer 6 located between the auxiliary electrodes 7 and the encapsulation region. The pixel defining layer 12 is etched to form an aperture of a trapezoidal structure. The bottom of the trapezoidal structure is the first electrode layer 2 and the buffer layer.
In S4, an organic light-emitting layer 3 and a second electrode layer 4 are made by an evaporation method on the basis of step S3, where the organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the aperture.
In S5, an encapsulation layer 10 is made on the basis of step S4, where the encapsulation layer 10 is a glass encapsulation cover. The UV glue is coated on the glass encapsulation cover which is then sealed and connected to the buffer layer at the position of the encapsulation region on the substrate, thereby achieving the encapsulation of the entire pixel region, as shown in
The materials and thicknesses of each layer in this embodiment are as described below.
Substrate 1 is made of an alkali-free glass.
For the buffer layer 6 a layer of silicon nitride of 100 nm is deposited through high temperature CVD process, the temperature of the process is 350° C., the adhesion force to the substrate is 5B, and the refractive index is 1.8.
The auxiliary electrode 7 is AlTi, the top of the structure is Ti with a thickness of 50 nm, and the thickness of Al is 300 nm. The patterning by dry etching process is made through Cl2 and BCl3, with a taper angle of 70°. Etching is not limited to dry etching, and the wet etching may also be used. A certain proportion of the mixed acid solution H3PO4, CH3COOH and HNO3 is used for etching.
For the first electrode layer 2, indiumtin oxide (ITO) is sputtered by PVD, with a thickness of 150 nm, and patterning is performed by wet (acid etching) process.
The pixel defining layer 12 located above the first electrode layer is made of SiN, adopts the same process as the buffer layer, and has a thickness of 300 nm. The grid size is 400 μm*400 μm. The pixel defining layer is patterned and formed by dry etching process.
Organic light-emitting layer 3: The organic light-emitting layer 3 includes, but is not limited to, a hole injection layer (HIL), a hole transport layer (HTL), a light-emitting layer (EML), an electron transport layer (ETL), and an electron injection layer (EIL).
Second electrode layer 4: The second electrode layer 4 includes an Al electrode, an MgAg electrode, and a metal oxide electrode (such as the ITO). For example, a layer of Al with a thickness of 200 nm is sputtered by the thermal evaporation.
Encapsulation layer 10: The organic light-emitting layer 3 is encapsulated by combinations of a traditional glass encapsulation cover and the UV glue or frit.
On the basis of Embodiment 1, different materials of the auxiliary electrode 7 and different materials of the buffer layer 6 are selected. Preferably, the etching selection ratio of the material of the pixel defining layer 12 to the material of the buffer layer 6 is 1.
The effects of different etching selection ratios of the auxiliary electrode to the buffer layer are shown in the following table:
It can be seen from the above table that when the etching selection ratio of the material of the auxiliary electrode 7 to the material of the buffer layer 6 is relatively small (<0.5), the buffer layer is easy to be etched away, resulting in the side etching problem as shown in
The basic structure of an OLED device provided by the present disclosure is the same as that of Embodiment 1, and the difference is that: the encapsulation layer in this embodiment adopts a thin film encapsulation structure, as shown in
In S1, a substrate 1 is divided into a pixel region 11 and an encapsulation region surrounding the pixel region 11, a buffer layer 6 is deposited on the pixel region, an auxiliary electrode layer is manufactured on the buffer layer 6 which is etched to form a number of auxiliary electrodes 7 arranged at intervals, and the taper angle of the auxiliary electrode 7 is 70°.
In S2, a first electrode layer 2 is manufactured on the basis of step S1, where the first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7. The first electrode layer 2 located between the auxiliary electrodes 7 and the encapsulation region is removed by etching process in order to expose the buffer layer 6.
In S3, a pixel defining layer 12 is deposited on the basis of step S2, where the pixel defining layer 12 covers the first electrode layer 2 and the buffer layer 6 located between the auxiliary electrode 7 and the encapsulation region; the pixel defining layer 12 is etched to form an aperture of a trapezoidal structure, where the bottom of the trapezoidal structure is the first electrode layer 2 and the buffer layer.
In S4, an organic light-emitting layer 3 and a second electrode layer 4 are made by an evaporation method on the basis of step S3, and the organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the aperture.
In S5, an encapsulation layer 10 is made on the basis of step S4, where the encapsulation layer 10 here adopts a thin film encapsulation method, such as inorganic layer/organic layer/inorganic layer. The inorganic layer can be deposited by chemical vapor deposition (CVD) so that thin film deposition is performed, and the organic layer can be printed by inkjet printing (IJP) so that thin film printing is performed. For example, SiO (1 μm)/IJP (8 μm)/SiO (1 μm) is used. The encapsulation layer 10 covers the entire pixel region 11, and the encapsulation region 9 surrounding the pixel region 11 seals and protects the entire pixel region 11.
In S6, an encapsulation transition layer 18 is coated on the cover plate 5, and then the cover plate 5 covers the encapsulation layer, thereby achieving encapsulation of the entire pixel region.
Compared with Embodiment 1, this embodiment adopts the film encapsulation method, which can further improve the encapsulation reliability of the panel.
As shown in
A light-emitting region of the substrate 1 is provided with a buffer layer 6. The buffer layer 6 is provided with a short-circuit prevention structure layer 13 formed by the first electrode layer and with a number of auxiliary electrodes 7 arranged at intervals. A first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7, the first electrode layer 2 located on one or two sides of the auxiliary electrode 7 is removed by etching process to expose the buffer layer 6, and the width of the removed first electrode layer 2 is H=10 μm. A short-circuit prevention structure is introduced through the patterning of the first electrode, which can prevent the device from failure due to the short circuit of the device during the long-term aging (such as long-term lighting).
As shown in
Referring to
The width of the region at which the pixel defining layer 12 is in direct contact with the buffer layer located on one or two sides of each auxiliary electrode is 10 μm.
A manufacturing method of an OLED device of this embodiment, as shown in
In S1, a substrate 1 is divided into a pixel region 11 and an encapsulation region surrounding the pixel region 11, a buffer layer 6 is deposited on the pixel region, an auxiliary electrode layer is manufactured on the buffer layer 6 which is etched to form a number of auxiliary electrodes 7 arranged at intervals, and the taper angle of the auxiliary electrode 7 is 70°.
In S2, a first electrode layer 2 is manufactured on the basis of step S1, where the first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7. The first electrode layer 2 located on one or two sides of the auxiliary electrode 7 is etched in order to expose the buffer layer 6, and etching is performed to form the short-circuit prevention structure layer 13.
In S3, a pixel defining layer 12 is deposited on the basis of step S2, where the pixel defining layer 12 covers the first electrode layer 2 and the buffer layer 6 located between the auxiliary electrodes 7 and the encapsulation region. The pixel defining layer 12 is etched to form an aperture of a trapezoidal structure. The bottom of the trapezoidal structure is the first electrode layer 2 and the buffer layer.
In S4, an organic light-emitting layer 3 and a second electrode layer 4 are made by an evaporation method on the basis of step S3, and the organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the aperture.
In S5, an encapsulation layer 10 is made on the basis of step S4, where the encapsulation layer 10 here adopts a thin film encapsulation method, such as inorganic layer/organic layer/inorganic layer. The inorganic layer can be deposited by chemical vapor deposition (CVD) so that thin film deposition is performed, and the organic layer can be printed by inkjet printing (IJP) so that thin film printing is performed. For example, SiO (1 μm)/IJP (8 μm)/SiO (1 μm) is used. The encapsulation layer 10 covers the entire pixel region 11, and the encapsulation region 9 surrounding the pixel region 11 seals and protects the entire pixel region 11.
In S6, an encapsulation transition layer 18 is coated on the cover plate 5, and then the cover plate 5 covers the encapsulation layer, thereby achieving the encapsulation of the entire pixel region.
The basic structure of an OLED device provided by the present disclosure is the same as that of Embodiment 3, and the difference from Embodiment 3 is as described below.
As shown in
A substrate 1 is made of an alkali-free glass and the conventional substrate structure shown in
An auxiliary electrode 7 is AlTi, the thickness of top titanium is 50 nm, and the thickness of the Al is 300 nm; the structure shown in
For a first electrode layer, indium tin oxide (ITO) is sputtered by PVD, with a thickness of 150 nm.
A pixel defining layer located above the first electrode layer is made of SiN, uses the same process as the buffer layer, and has a thickness of 300 nm; and the size of the grid is 400 μm*400 μm.
An organic light-emitting layer includes an HIL, an HTL, an EML, an ETL and an EIL.
A second electrode includes an Al electrode, and a layer of Al with a thickness of 200 nm is deposited by thermal evaporation.
An encapsulation layer is a glass encapsulation cover, and the encapsulation region of the substrate and the encapsulation cover are sealed by the UV glue to improve the encapsulation reliability of the panel.
The experimental test results are as described below.
The service life test is performed at 1000 nits. It can be seen that for the device of the present disclosure, the service life of the OLED device can be increased by 5 times due to the addition of the buffer layer. It shows that adding a buffer layer can significantly improve the reliability of the panel. The main reasons are as described below.
Due to the existence of the buffer layer, the first electrode or the auxiliary electrode forms a more acute taper angle by dry etching process, that is, with the buffer layer disposed, the “undercut” phenomenon of the auxiliary electrode can be well improved, the occurrence of “side etching” can be avoided, and the taper angle of the auxiliary electrode can be better modified, thereby improving the overlap of the subsequent organic/metal/encapsulation film layers.
Furthermore, the added buffer layer can block the penetration of metal ions in the glass substrate into the first electrode layer/auxiliary electrode, avoid occurrence of electrochemical corrosion, and improve the stability of the OLED device.
After the test, the average service life of the device in Embodiment 1 is 500 h@1000 nit, and the failure rate of the device at 1000 H under long-term aging is 20%.
The average service life of the device in Embodiment 2 is 550 h @1000 nit, and the failure rate of the device at 1000 H under long-term aging is 10%.
The average service life of the device in Embodiment 3 is 560 h@1000 nit, and because of the addition of the short-circuit prevention structure, the device does not fail at 1000 H under long-term aging.
The average service life of the device in Embodiment 4 is 600 h@1000 nit, and because of the addition of the short-circuit prevention structure, the device does not fail at 1000 H under long-term aging.
The average service life of the device in Comparative embodiment 1 is 100 h@1000 nit.
Through comparison, the embodiments 1 to 4 used in the present disclosure can greatly improve the life of the device compared with the existing art.
In this embodiment, on the basis of Embodiment 3, the continuous dam structures surrounding the entire pixel region are provided at the buffer layer located in the encapsulation region, as shown in
A manufacturing method of an OLED device includes the steps described below.
In S1, a substrate 1 is divided into a pixel region 11 and an encapsulation region surrounding the pixel region 11, a buffer layer 6 is deposited at the pixel region, an auxiliary electrode layer is manufactured on the buffer layer 6 which is etched to form a number of auxiliary electrodes 7 arranged at intervals, and the taper angle of the auxiliary electrode 7 is 70°.
In S2, a first electrode layer 2 is manufactured on the basis of step S1. The first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7. The first electrode layer 2 located on one or two sides of the auxiliary electrode 7 is removed by etching process in order to expose the buffer layer 6, and etching is performed to form the short-circuit prevention structure layer 13.
In S3, a pixel defining layer 12 is deposited on the basis of step S2, where the pixel defining layer 12 covers the first electrode layer 2 and the buffer layer 6 located at the encapsulation region. The pixel defining layer 12 is etched to form an aperture of a trapezoidal structure, and a raised dam structure (DAM) is formed at the encapsulation region.
In S4, an organic light-emitting layer 3 and a second electrode layer 4 are made by an evaporation method on the basis of step S3, and the organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the aperture.
In S5, an encapsulation layer 10 is fabricated by chemical vapor deposition on the basis of step S4. The organic light-emitting layer 3, the second electrode layer 4 and an encapsulation layer are sequentially formed on the pixel defining layer 12 and the aperture. At the same time, the encapsulation layer at the encapsulation region is in direct contact with the buffer layer to form thin film encapsulation.
In S6, an encapsulation transition layer, such as the UV glue or OCA glue, is attached on the basis of step S5, and then a cover plate is attached to the encapsulation transition layer for sealing, where the cover plate may include glass, copper foil, aluminum foil, and the like.
The difference from Embodiment 5 is that this embodiment uses a patterned structure on the buffer layer located at the encapsulation region. As shown in
A manufacturing method of an OLED device includes the steps described below.
In S1, a substrate 1 is divided into a pixel region 11 and an encapsulation region surrounding the pixel region 11, a buffer layer 6 is deposited at the pixel region, and the buffer layer 6 is patterned at the encapsulation region to form two groove structures 16. An auxiliary electrode layer is manufactured on the buffer layer 6 which is etched to form a number of auxiliary electrodes 7 arranged at intervals, and the taper angle of the auxiliary electrode 7 is 70°.
In S2, a first electrode layer 2 is manufactured on the basis of step S1, where the first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7. The first electrode layer 2 located on one or two sides of the auxiliary electrode 7 is removed by etching process in order to expose the buffer layer 6, and etching is performed to form the short-circuit prevention structure layer 13.
In S3, a pixel defining layer 12 is deposited on the basis of step S2, where the pixel defining layer 12 covers the first electrode layer 2 and the buffer layer 6 located at the encapsulation region. The pixel defining layer 12 is etched to form an aperture of a trapezoidal structure, and a raised dam structure (DAM) is formed at the inner side of the encapsulation region.
In S4, an organic light-emitting layer 3 and a second electrode layer 4 are made by an evaporation method on the basis of step S3, and the organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the aperture.
In S5, an encapsulation layer 10 is fabricated by chemical vapor deposition on the basis of step S4. The organic light-emitting layer 3, the second electrode layer 4 and an encapsulation layer are sequentially formed on the pixel defining layer 12 and the aperture. At the same time, the encapsulation layer at the encapsulation region is in direct contact with the buffer layer to form thin film encapsulation.
In S6, an encapsulation transition layer, such as the UV glue or OCA glue, is attached on the basis of step S5, and then a cover plate is attached to the encapsulation transition layer for sealing, where the cover plate may include glass, copper foil, aluminum foil, and the like.
Of course, the patterned structure provided at the encapsulation region is not limited to the structures shown in
A manufacturing method of an OLED device, as shown in
In S1, a substrate 1 is divided into a pixel region 11 and an encapsulation region surrounding the pixel region 11, a buffer layer 6 is deposited at the pixel region, an auxiliary electrode layer is manufactured on the buffer layer 6 which is etched to form a number of auxiliary electrodes 7 arranged at intervals, and the taper angle of the auxiliary electrode 7 is 70°.
In S2, a first electrode layer 2 is manufactured on the basis of step S1, where the first electrode layer 2 covers the buffer layer 6 and the auxiliary electrode 7. The first electrode layer 2 located on one or two sides of the auxiliary electrode 7 is removed by etching process in order to expose the buffer layer 6, and etching is performed to form the short-circuit prevention structure layer 13.
In S3, a pixel defining layer 12 is deposited on the basis of step S2, where the pixel defining layer 12 covers the first electrode layer 2 and the buffer layer 6 located at the encapsulation region. The pixel defining layer 12 is etched to form an aperture of a trapezoidal structure.
In S4, an organic light-emitting layer 3 and a second electrode layer 4 are made by an evaporation method on the basis of step S3, and the organic light-emitting layer 3 and the second electrode layer 4 are sequentially formed on the pixel defining layer 12 and the aperture.
In S5, an encapsulation layer 10 is fabricated by chemical vapor deposition on the basis of step S4. The organic light-emitting layer 3, the second electrode layer 4 and an encapsulation layer are sequentially formed on the pixel defining layer 12 and the aperture. At the same time, the encapsulation layer at the encapsulation region is in direct contact with the buffer layer.
In S6, an encapsulation transition layer, such as the UV glue or OCA glue, is attached on the basis of step S5, and then a cover plate is attached to the encapsulation transition layer for sealing, where the cover plate may include glass, copper foil, aluminum foil, and the like.
After the test, the average service life of the device of Embodiment 5 of the present disclosure is 1000 h@1000 nit, the average service life of the device of Embodiment 6 is 1050 h@1000 nit, and the average service life of the device of Comparative embodiment 2 is 580 h@1000 nit. Therefore, the service life of the device is greatly improved.
Therefore, it is illustrated that the patterned buffer layer and pixel defining layer at the encapsulation region can greatly improve the service life of the device.
Apparently, the above-mentioned embodiments are merely examples for clear description and are not intended to limit the implementation. For those of ordinary skill in the art, other changes or modifications in different forms can be made on the basis of the above description. It is unnecessary and impossible to list all the implementations here. The apparent changes or modifications derived from this are still within the scope of the present disclosure.
It is to be understood that the foregoing is a description of one or more preferred exemplary embodiments of the invention. The invention is not limited to the particular embodiment(s) disclosed herein, but rather is defined solely by the claims below. Furthermore, the statements contained in the foregoing description relate to particular embodiments and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiment(s) will become apparent to those skilled in the art. All such other embodiments, changes, and modifications are intended to come within the scope of the appended claims.
As used in this specification and claims, the terms “for example,” “e.g.,” “for instance,” “such as,” and “like,” and the verbs “comprising,” “having,” “including,” and their other verb forms, when used in conjunction with a listing of one or more components or other items, are each to be construed as open-ended, meaning that the listing is not to be considered as excluding other, additional components or items. Other terms are to be construed using their broadest reasonable meaning unless they are used in a context that requires a different interpretation.
Number | Date | Country | Kind |
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201910113418.6 | Feb 2019 | CN | national |
This is a national stage application filed under 37 U.S.C. 371 based on International Patent Application No. PCT/CN2020/075133, filed Feb. 13, 2020, which claims priority to Chinese Patent Application No. 201910113418.6 filed with the CNIPA Feb. 14, 2019, the disclosure of which are incorporated herein by reference in their entireties.
Filing Document | Filing Date | Country | Kind |
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PCT/CN2020/075133 | 2/13/2020 | WO | 00 |