Light emitting device with improved light output coupling

Abstract

An optoelectronic device including a composite film in a multilayer packaging stack is provided. Also provided is a method of forming a light reflection modifying structure and other polymer device layers using inkjet printing. The composite film includes a first lower refractive index domain and a second higher refractive index domain.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 607,824, filed on December 19, 2017, the entire contents of which are hereby incorporated by reference. Background Art

[0003] Multilayer packaging stacks composed of alternating inorganic and organic polymer films have been used to protect light-emitting devices from the damaging effects of exposure to water vapor and oxygen. Unfortunately, the difference between the refractive index (RI) between an inorganic layer in the stack and its adjacent lower refractive index organic polymer layer can result in total internal reflection of light at the interface between the two layers, which reduces the fraction of light that is able to leave the device. Furthermore, even in the absence of a high RI mismatch between the inorganic and organic polymer layers, light-emitting devices can suffer from limited light output due to total internal reflection of light at the interface between a terminal layer in the packaging stack and an overlying device layer, or at the interface between a terminal layer and air in the packaging stack in the absence of an overlying device layer. Technical Field

[0005] The invention described herein relates to package stacks and light emitting devices, such as organic light emitting diode (OLED) devices including multi-layer package stacks. The multi-layer package stacks provide reduced total internal reflection and thus improved light output efficiency relative to conventional package stacks. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1A is a schematic diagram illustrating a cross-sectional view of one embodiment of an OLED device including a multi-layer encapsulation stack having a composite film wherein a single high refractive index dome-shaped structure is disposed over each sub-pixel of the device. Figure 1B is a top view of an OLED device.

[0007] Figure 2 is a schematic diagram showing a cross-sectional view of a second embodiment of an OLED device including a multi-layer encapsulation stack having a composite film in which a single high refractive index cylindrical structure is disposed over each sub-pixel of the device.

[0008] Figure 3 is a schematic diagram illustrating a cross-sectional view of one embodiment of an OLED device including a multi-layer encapsulation stack having a composite film wherein a plurality of high refractive index dome-shaped structures are disposed over each sub-pixel of the device.

[0009] Figure 4is a schematic diagram illustrating a top view of another embodiment of an OLED device including a multi-layer encapsulation stack having a composite film, wherein a plurality of high refractive index dome-shaped structures are disposed on each sub-pixel of the device.

[0010] Figure 5A is a schematic diagram showing a cross-sectional view of an OLED device having a composite film on top of its multi-layer encapsulation stack.

[0011] Figure 5B is shown in more detail Figure 5A Schematic diagram of a multi-layer packaging stack.

[0012] Figure 6 Is manufacturing Figure 1A and Figure 1B Schematic diagram of the method for producing an OLED device.

[0013] Figure 7 Is manufacturing Figure 2 Schematic diagram of the method for producing an OLED device. Specific embodiments

[0014] The devices described herein include various electronic and optoelectronic devices in which the active area of ​​the device is encapsulated using a protective multi-layer encapsulation stack. In an OLED or other electronic or optoelectronic device, the "active area" need not meet any requirements for electrical energy amplification or transistor activity, and can generally refer to an area where electrical activity or optoelectronic activity (e.g., light emission, light absorption, or light conversion) can occur. The active area itself will typically be a multilayer structure composed of multiple device layers, including, for example, electrodes, charge injection layers, charge transport layers, and / or light-emitting layers. Although top-emitting OLED devices are used below as illustrative examples to describe the various benefits of encapsulation stacks, encapsulation stacks can be applied to other light-emitting devices, including other top-emitting lighting devices, top-emitting quantum dot (QD)-LED devices, micro-LED displays, and QD-photoluminescence (PL) emission color converters. In addition, the technology can be applied to light sensors and photocells, where a large amount of light coupled into the device is advantageous.

[0015] exist Figure 1A FIG. 1 is a schematic diagram of a cross-sectional view of an embodiment of an OLED device 100, wherein the OLED device 100 includes a multi-layer package stack. Figure 1B. This embodiment of an OLED device includes a plurality of active areas 104 and an OLED device substrate 102. A multi-layer encapsulation stack 106 is disposed above the active areas 104. The multi-layer encapsulation stack 106 (which protects the underlying active areas 104 from degradation due to exposure to air and / or moisture) includes a first inorganic barrier layer 108 that inhibits exposure of the active areas 104 to water vapor, oxygen, and / or other reactive gases present in the surrounding atmosphere. Adjacent to the first inorganic barrier layer 108 is a composite film 109 that includes a first domain that includes a first polymer layer 110. The first polymer layer 110 is composed of one or more organic polymers and provides a planarization layer to planarize the encapsulation stack. In Figure 1A In the embodiment of the OLED device shown, the multilayer encapsulation stack 106 includes a second inorganic barrier layer 108A disposed above the composite film 109. In other embodiments of the encapsulation stack, the order of the layers can be reversed, such that the composite film 109 is first fabricated, followed by the first inorganic barrier layer 108. In such an embodiment, a second planarizing polymer layer and a second inorganic barrier layer can then be deposited in sequence to provide adequate encapsulation for the underlying device. Thus, a modified process includes depositing the composite film 109 directly on top of the active area of ​​the device, followed by deposition of the first inorganic barrier layer, followed by deposition of the second polymer layer, followed by deposition of the second inorganic barrier layer. Additionally, a greater or lesser number of inorganic barrier layers and polymer layers can be provided. For example, Figure 1A The package stack may have a second polymer layer disposed on the second inorganic barrier layer 108A. Figure 1A The active area 104 of the OLED device may be light emitting sub-pixels (e.g., red, green, and / or blue sub-pixels) embedded in or supported by the substrate of the OLED device 102. Each of these sub-pixels may include an organic light emitting layer disposed between a first electrode (e.g., a cathode) and a second electrode (e.g., an anode). Optionally, an electron transport layer and / or an electron injection layer may be disposed between the cathode and the light emitting layer, and a hole transport layer and / or a hole injection layer may be disposed between the anode and the light emitting layer.

[0016] At least one layer in the package stack is a composite film comprising a first domain formed of a first polymer and a second domain formed of a second polymer, wherein the second domain has a higher RI than the first domain, and further wherein the second domain desirably has an RI that is the same or nearly the same as the RI of the inorganic material of the first inorganic barrier layer 108. The second domain may be a discontinuous domain comprising a plurality of subdomains, typically surrounded by or embedded in the first domain. For example, in Figure 1A and Figure 1BIn the illustrated embodiment of the composite film 109, the subdomains are a plurality of dome-shaped structures 112. Due to the reduced RI mismatch between the subdomains 112 and the inorganic barrier layer 108, the total internal reflection of light emitted from the subpixel 104 at the interface between the inorganic barrier layer 108 and the structure 112 is reduced. The appropriate RI for the subdomain 112 will depend on the RI of the inorganic barrier layer. In some embodiments of the multi-layer package stack, the RI of the subdomain and the inorganic barrier layer differ by no more than ±15%, including no more than 10%, and also including no more than 5%. By way of illustration only, for an inorganic barrier layer comprising SiNx having an RI in the range of about 1.85 to about 2.2, the subdomain may have an RI of about 1.7 or higher.

[0017] The material for preparing the higher RI domain can be a polymer material comprising one or more organic polymers or polymer composites, including a polymer material comprising inorganic particles dispersed in a polymer matrix. Suitable polymers include acrylic, urethane and epoxy resins. Suitable inorganic particles include metal oxide particles, such as zirconium oxide, titanium oxide, hafnium oxide, zinc oxide and mixtures of two or more thereof. Optionally, the inorganic oxide particles can be surface functionalized with a capping agent that improves its dispersibility in the polymer matrix. Such capping agents may include 2-[2-(2-9-methoxyethoxy)ethoxy]acetic acid and / or methoxy(triethyleneoxy)propyltrimethoxysilane and / or 3-methacryloxypropyltrimethoxysilane and / or n-n-octyltrimethoxysilane and / or dodecyltrimethoxysilane and / or m,p-p-ethylphenethyltrimethoxysilane. In some embodiments, the same metal oxide is present in the higher RI domain and the inorganic barrier layer of the composite film. Merely by way of illustration, the high RI polymer-nanocrystal composite materials for nanocomposite coatings described in U.S. Patent Publication No. 2014 / 0322549, the entire disclosure of which is incorporated herein by reference, may be used to form higher RI domains in the composite films of the multilayer packaging stacks described herein.

[0018] exist Figure 1A In embodiments of composite films of the invention, subdomains 112 provide non-planar interfaces between the higher RI material of the subdomain and the lower RI material of the first domain, such that they change the angle of light reflected at the interface, so that total internal reflection is suppressed and light outcoupling and extraction are enhanced. In some embodiments of the higher RI domain material including particles, the particles can act as scattering centers to further reduce internal reflection and light capture. However, for applications where light scattering is not desired, the particles can have a diameter small enough to avoid or minimize light scattering. The subdomains of the composite film can have a variety of shapes and sizes. For example, as Figure 1AAs shown, the subdomains can be structures such as hemispheres (domes) arranged in a regular array or a random pattern. Once formed, the structure can be covered by a layer of the lower RI polymer material of the first domain to form a smooth planar or substantially planar surface, on which the next inorganic barrier layer can be formed. Alternatively, the subdomains can be cylinders 114 arranged in a regular array or a random pattern, such as Figure 2 As shown. In this embodiment of the device, the first domain 110 surrounds the cylinder 114, and the surface formed by the first domain 110 and the cylinder 114 provides a smooth planar or substantially planar surface on which the next inorganic barrier layer 108A can be formed. The use of a cylindrical structure can be beneficial because light reflected at the vertical interface 116 formed between the cylindrical sub-domain 114 and the first domain 110 can be directed toward the light emitting surface of the device, thereby further reducing the capture of light in the first inorganic barrier layer 108 and / or the active region 104.

[0019] The size and location of the subdomains are not strictly limited, so long as they are capable of reducing total internal reflection within the device. For example, various embodiments of subdomains including hemispherical structures have a radius in the range of 1 µm to 50 µm, an inter-structure spacing (pitch) in the range of 1 µm to 100 µm, and / or a height in the range of 1 µm to 50 µm; however, dimensions outside of these ranges may be used. Once formed, the subdomains may be covered by or laterally surrounded by a layer of lower RI polymer material of the first domain to form a smooth planar or substantially planar composite film surface, on which the next inorganic barrier layer may be formed. Alternatively, the first domain and the second domain may be formed simultaneously into a composite film having a smooth planar or substantially planar surface, on which the next inorganic barrier layer may be formed.

[0020] To avoid or reduce color bleeding and other undesirable visual effects, the sub-domains may be patterned (e.g., inkjet printed) at a resolution commensurate with the resolution of the display device. For example, in some embodiments of a multi-layer packaging stack, there is one sub-domain associated with each pixel or with each sub-pixel within a pixel, such as Figure 1A , Figure 1B and Figure 2 In other embodiments, the sub-fields are much smaller than pixels or sub-pixels, so that multiple sub-fields are provided on each pixel or sub-pixel. For example, the sub-fields may be located in clusters on each pixel or sub-pixel in the display device. Figure 3 As schematically shown in Figure 3A cross-sectional view of a portion of a display device is shown, the display device including an OLED sub-pixel 304 on which an encapsulation stack 306 is disposed. The encapsulation stack 306 includes a first inorganic barrier layer 308, a composite film 309, and a second inorganic barrier layer 308A over the composite film 309, the composite film 309 including a first domain 310, a second domain including a plurality of dome-shaped sub-domains 312 clustered over the OLED 304.

[0021] exist Figure 4 The concept of having more than one sub-domain of a composite film on a single sub-pixel is further illustrated in Figure 4 A top view of three sub-pixels (red (R), green (G), and blue (B)) is shown, each sub-pixel being associated with three overlying sub-domains 412 of the composite film.

[0022] An advantage of implementing the composite film on top of the first (i.e., lowest) inorganic barrier layer in a multi-layer encapsulation stack, rather than on top of the encapsulation stack, is that such placement reduces the distance between the light-emitting layer of the sub-pixel and the high RI sub-domain of the composite film. This is advantageous because it helps reduce color bleeding, which can reduce the perceived resolution, black contrast, and / or color gamut of the OLED display.

[0023] Despite Figure 1A , Figure 1B and Figure 2 In the illustrated device embodiment, the composite film is positioned directly on the first inorganic barrier layer of the package stack, but in other embodiments, the composite film can be formed on a second (or higher) inorganic barrier layer in the package stack. For example, the composite film can be placed on the top inorganic barrier layer of the package stack, such as Figure 5A and Figure 5B In addition, the composite film can be provided on more than one inorganic barrier layer in a multi-layer encapsulation stack. In other embodiments, the composite film can be placed directly on the top surface of the underlying active area (e.g., on the top electrode of the OLED stack) to provide the first layer of the encapsulation stack.

[0024] In embodiments where the composite film is placed over a second or higher inorganic barrier layer in the package stack, all layers in the package stack below the composite film, including the polymer planarization layer, should be made of high RI materials. In such embodiments, the underlying planarization layer may have the same material composition as the second domain in the composite film. However, the planarization layer and the second domain of the composite film do not have to have the same composition, as long as the planarization layer has an RI that is the same or nearly the same (e.g., differs by no more than 15%) as the RI of the inorganic material of the inorganic barrier layer in the package stack. By way of illustration only, for an inorganic barrier layer comprising SiNx having an RI in the range of about 1.85 to about 2.2, the high RI planarization layer may have an RI of about 1.7 or higher.

[0025] Figure 5A An embodiment of an OLED display device including a composite film as the last layer of an encapsulation stack is schematically shown in . The figure is a cross-sectional view and includes components of an active area 530 of the OLED device. These include a reflective anode 522, an organic layer stack 524, and a semi-transparent cathode 526. An encapsulation stack 506 and a top protective glass layer 528 are disposed above the active area 530. The organic layer stack 524 may include, from top to bottom, an electron injection layer, an electron transport layer, a light-emitting layer, a hole transport layer, and a hole injection layer. The OLED device may also include a supporting substrate 520. In the embodiment shown here, the last layer of the encapsulation stack 506 includes a composite film 509 of the type described herein disposed on another encapsulation stack layer 511 (shown here as a single block for simplicity). Figure 5B A more detailed cross-sectional view of the encapsulation layer 506 with an upper composite film 509 is shown. The composite film has Figure 3 The structure shown is similar to that shown, except that the composite film 509 is on top of the package stack and the underlying layers of the package stack include one or more inorganic barrier layers 507 having a high RI material (which may be the same material as that forming the subdomains 512). For simplicity, Figure 5A and 5B All layers in the display device shown in are shown as having the same thickness. However, as will be appreciated by one of ordinary skill in the art, layers in an actual display device will have different thicknesses depending on their specific functions. For example, the organic layer stack will typically be significantly thinner than the encapsulation stack layers 511 and 509.

[0026] The use of a composite film including a high RI domain within a layer of an encapsulation stack can significantly improve the light extraction efficiency and integrated current (or overall current) efficiency of an OLED device including the film relative to an OLED device that does not include such a film but is otherwise identical. By way of illustration, various embodiments of encapsulation stacks according to the present teachings increase the extraction efficiency of an OLED device by at least 30% (e.g., 30% to 40%) and increase the integrated current efficiency of an OLED device by at least 70% (e.g., 70% to 100%). In addition, encapsulation stacks including the composite film can reduce the viewing angle dependence of the emitted light, resulting in a higher quality display.

[0027] Examples of inorganic materials that can be used to fabricate the inorganic barrier layer of the multilayer package stack may include, for example, various nitrides, oxides, and oxynitrides, such as silicon nitride (SiNx), silicon oxide, Al 2 O 3 、TiO 2 , HfO 2 and silicon oxynitride (SiO X N Y The inorganic barrier layer may be deposited or otherwise formed on the active area and may be blanket coated (e.g., via chemical and / or physical vapor deposition) over the entire or substantially the entire exposed surface of the substrate and active area.

[0028] The polymers that can be used to make the first and second domains of the composite film and other polymer planarization layers of the multilayer encapsulation stack include various polymer materials that can be cured using one or more of heat (e.g., baking), radiation (e.g., ultraviolet exposure) or other energy-based (e.g., electron beam) curing techniques, and once cured, a polymer film and / or polymer structure can be formed. Various polymer deposition techniques can be used to form various polymer layers of the encapsulation stack. In some embodiments of the OLED device, the polymer layer of the encapsulation stack, including the composite film, is formed by inkjet printing an ink composition containing a curable monomer, oligomer and / or polymer onto a substrate (e.g., onto an inorganic barrier layer) and curing the composition to form a polymer film. In addition, the ink composition may include one or more crosslinking agents, polymerization initiators and / or solvents. The polymer planarization layer can also be prepared by applying the ink composition to the device substrate using a coating technique other than inkjet printing, and then curing the composition to form a polymer film.

[0029] Examples of acrylate and methacrylate (collectively referred to herein as (meth)acrylate) monomers that may be included in the ink composition include mono(meth)acrylate monomers, di(meth)acrylate monomers, and higher functional (meth)acrylate monomers. In various embodiments of the ink composition, the (meth)acrylate monomer is a polyether. In various embodiments of the ink composition, the (meth)acrylate monomer is an alkoxylated aliphatic di(meth)acrylate monomer. These include di(meth)acrylates containing neopentyl glycol groups, including alkoxylated neopentyl glycol diacrylates, such as neopentyl glycol propoxylate di(meth)acrylate and neopentyl glycol ethoxylate di(meth)acrylate. Other suitable (meth)acrylate monomers include, but are not limited to: alkyl (meth)acrylates, such as methyl (meth)acrylate, ethyl (meth)acrylate, and benzyl methacrylate; cyclic trimethylolpropane formal (meth)acrylate; alkoxylated tetrahydrofurfuryl (meth)acrylate; phenoxyalkyl (meth)acrylates, such as 2-phenoxyethyl (meth)acrylate and phenoxymethyl (meth)acrylate; 2-(2-ethoxyethoxy)ethyl (meth)acrylate. Other suitable di(meth)acrylate monomers include: 1,6-hexanediol diacrylate, 1,12-dodecanediol di(meth)acrylate; 1,3-butanediol di(meth)acrylate; di(ethylene glycol dimethyl)acrylate methyl and polyethylene glycol di(meth)acrylate monomers. Other mono- and di-(meth)acrylate monomers that may be included in various embodiments of the ink composition, either alone or in combination, include: dicyclopentenyloxyethyl acrylate (DCPOEA), isobornyl acrylate (ISOBA), dicyclopentenyloxyethyl methacrylate (DCPOEMA), isobornyl methacrylate (ISOBMA), and N-octadecyl methacrylate (OctaM). Homologs of ISOBA and ISOBMA (collectively referred to as "ISOB(M)A" homologs) may also be used, wherein one or more methyl groups on the ring are replaced with hydrogen.

[0030] The multifunctional (meth)acrylate crosslinking agent desirably has at least three reactive (meth)acrylate groups. Thus, the multifunctional (meth)acrylate crosslinking agent may be, for example, a tri(meth)acrylate, a tetra(meth)acrylate and / or a higher functional (meth)acrylate. Pentaerythritol tetraacrylate or pentaerythritol tetramethacrylate, di(trimethylolpropane) tetraacrylate, trimethylolpropane triacrylate and di(trimethylolpropane) tetramethacrylate are examples of multifunctional (meth)acrylates that may be used as primary crosslinking agents. The term "primarily" as used herein means that other components of the ink composition may also participate in crosslinking, although this is not their primary functional purpose.

[0031] The compositions used to form the nanocomposite coating in U.S. Patent Application Publication No. 2014 / 0322549 are examples of ink compositions that can be used to form the second domain of the composite film and / or any high RI planarizing layer in the package stack. The ink compositions described in U.S. Patent Application Nos. US 20160024322, US 2017 / 0062762, and US 2017 / 0358775 are examples of ink compositions that can be used to form the first domain of the composite film and / or other polymer planarizing layers in the multilayer package stack.

[0032] With respect to the properties of the ink composition applied via inkjet printing, the surface tension, viscosity, and wetting properties of the initial ink composition should be adjusted to allow the composition to be dispensed through the inkjet printing nozzle without drying or clogging on the nozzle at a temperature used for printing (e.g., room temperature; about 25°C). By way of illustration, some embodiments of the ink composition for forming the polymer layer have a viscosity between about 10 cP and about 28 cP (including, for example, between about 15 cP and about 26 cP) at 25°C, and a surface tension between about 28 dynes / cm and about 45 dynes / cm at 25°C. In order to adjust or optimize the ink composition for inkjet printing, solvents, surfactants, viscosity modifiers, etc. may be included in the ink composition. Suitable organic solvents include esters and ethers. In addition to addressing the viscosity and surface tension of the ink, the surface energy of the surface of the deposited ink composition may also be modified to achieve the desired ink extension. This may be accomplished by plasma treatment, exposure to a gas containing a surface modifier, and coating with a thin primer layer containing a surface modifier. These surface modifiers can also be deposited in a patterned manner, thereby forcing the ink to be pinned to defined locations on the substrate.

[0033] A manufacturing Figure 1A and Figure 1B A method of making an OLED device of the type shown in Figure 6Schematically shown in FIG. Initially, one or more active areas (e.g., sub-pixels) 104 are formed on a device substrate 102, and a first inorganic barrier layer 108 is deposited as a film on the active areas. Next, droplets of an ink composition 600 comprising materials of sub-domains constituting the composite film are deposited (e.g., inkjet printed) on the active areas 104 on the first inorganic barrier layer 108 (panel (a)). The droplets spread on the surface and solidify to form dome-shaped structures 112 (panel (b)). In the embodiment shown here, there is one dome-shaped structure for each active area. If the active areas include sub-pixels emitting different colors, the composition of the sub-domains can be independently adjusted to meet the desired optical properties of the different sub-pixels. Although not shown here, after printing, pixel banks can be used to confine the spread of the ink composition 600. Optionally, the ink composition 600 can be confined by patterning the substrate surface on which hydrophobic and / or hydrophilic regions are deposited, which control the wetting characteristics of the ink composition. Next, droplets of an ink composition 602 comprising the material constituting the first lower RI domain of the composite film are deposited (e.g., inkjet printed) as a coating on the first inorganic barrier layer 108 over the higher RI structure 112 (panel (c)). The coating is then cured to form the first domain 110. Finally, the second inorganic barrier layer 108A is deposited as a film on the first polymer layer constituting the first domain of the composite film 109 (panel (d)). In another approach, the higher RI ink composition 600 is not cured prior to depositing the lower RI ink composition 602. In this case, the two ink compositions are optimized so that they do not intermix, or so that they only partially intermix, thereby retaining the out-coupling advantages of the structure in the final device. In a variation of this process, the ink composition forming the subdomain structure 112 is cured after deposition but prior to depositing the lower RI ink composition 602 forming the first domain. In this case, the interface between the two cured domains is well defined and abrupt. This approach imposes fewer restrictions on the ink composition system because intermixing between the two ink compositions is inhibited by the curing step.

[0034] A manufacturing Figure 2 The method of the OLED device of the type shown is Figure 7Schematically shown in FIG. In this method, the ink composition 400 used to make the higher RI structure of the subdomain and the ink composition 602 used to make the first domain are designed so that they similarly wet the surface of the first inorganic barrier layer 108 to form a planar coating on the surface, but do not substantially intermix within the coating. Droplets of the ink compositions 600 and 602 can be printed (simultaneously or sequentially) onto the first inorganic barrier layer 108 without curing between the printing steps (panels (a) and (b)), and the coating can then be cured to form a cylindrical subdomain structure (or pyramid-like feature) 114 laterally enclosed in the polymer layer of the first domain 110, followed by deposition of the second inorganic barrier layer 108A (panel (c)). In this method, some intermixing between the ink compositions can be allowed, as long as the intermixing area is relatively small and the RI contrast between the two domains is preserved.

[0035] An industrial inkjet printing system that can be housed in a package configured to provide a controlled process environment can be used to deposit ink compositions onto a device substrate. Inkjet printing for depositing the ink compositions described herein can have several advantages. First, since inkjet-based manufacturing can be performed at atmospheric pressure, a series of vacuum processing operations can be eliminated. In addition, during the inkjet printing process, the ink composition can be localized to cover portions of the OLED substrate above and near the active area to effectively encapsulate the active area, including the lateral edges of the active area. Targeted patterning using inkjet printing leads to the elimination of material waste, as well as the elimination of additional processing that is typically required to achieve patterning of organic thin films (e.g., required by various masking techniques). The ink composition can be printed using, for example, a printing system such as that described in U.S. Patent No. 9,343,678.

[0036] The present teachings are intended to be illustrative, not restrictive. In the specification, various features may be grouped together to streamline the present disclosure. This should not be interpreted as intended to make unclaimed disclosed features essential to any claim. Rather, the subject matter of the invention may lie in less than all the features of a particular disclosed embodiment. Therefore, the appended claims are hereby incorporated into the detailed description as examples or embodiments, each claim existing independently as a separate embodiment, and it is conceivable that such embodiments may be combined with each other in various combinations or permutations. The scope of the present invention should be determined with reference to the appended claims together with the full scope of equivalents to which such claims are assigned.

Claims

1. A photoelectric device comprising: at least one activity area; as well as A multi-layer package stack disposed above the at least one active area, the multi-layer package stack comprising: an inorganic barrier layer; and A composite film, the composite film is close to the inorganic barrier layer and includes a first domain and a second domain, the second domain includes a plurality of discontinuous subdomains, Each of the subdomains comprises inorganic particles dispersed in a polymer matrix, and the second domain has a higher refractive index than the first domain.

2. The optoelectronic device according to claim 1, wherein: The optoelectronic device is an organic light emitting diode device and the at least one active area includes light emitting pixels.

3. The optoelectronic device according to claim 1, wherein: The plurality of sub-domains are surrounded by or embedded in the first domain.

4. The optoelectronic device according to claim 1, wherein: The inorganic barrier layer includes silicon nitride, silicon oxide, or silicon oxynitride.

5. The optoelectronic device according to claim 4, wherein: The second domain includes zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, or a mixture of two or more thereof dispersed in a polymer matrix.

6. The optoelectronic device according to claim 1, wherein: The second domain includes zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, or a mixture of two or more thereof dispersed in a polymer matrix.

7. The optoelectronic device according to claim 6, wherein: The polymer matrix is ​​an acrylic matrix.

8. The optoelectronic device according to claim 1, wherein: The subdomain is dome-shaped.

9. The optoelectronic device according to claim 1, wherein: The subdomain is cylindrical or conical in shape.

10. The optoelectronic device according to claim 1, wherein: The first domain includes a first polymer, and the second domain includes a second polymer.

11. A method of forming a packaged optoelectronic device, the method comprising: forming an inorganic barrier layer on at least one active area of ​​an optoelectronic device; inkjet printing a first curable ink composition as a plurality of droplets on the inorganic barrier layer; solidifying the plurality of droplets to form a second domain including a plurality of discontinuous subdomains on the inorganic barrier layer; inkjet printing a second ink component around the plurality of droplets or over the subdomains; as well as The second ink composition is cured to form a first domain including a polymer film around the subdomains, wherein each of the subdomains includes inorganic particles dispersed in a polymer matrix, and the second domain has a higher refractive index than the first domain.

12. The method according to claim 11, wherein: The optoelectronic device is an organic light emitting diode device and the at least one active area includes light emitting pixels.

13. The method according to claim 11, wherein: The plurality of droplets solidify to form the plurality of sub-domains before the second ink component is inkjet printed.

14. The method according to claim 13, wherein: The subdomain is dome-shaped.

15. The method according to claim 11, wherein: The second ink component is substantially immiscible with the first ink component, and further wherein: Before the first ink component and the second ink component are solidified, the second ink component is printed around the droplets of the first ink component.

16. The method according to claim 15, wherein: The subdomains are cylindrical or conical in shape.

17. The method according to claim 11, wherein: The first ink component includes inorganic particles and one or more curable monomers, oligomers, or polymers.

18. The method according to claim 17, wherein: The inorganic particles include zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, or a mixture of two or more thereof.

19. The method according to claim 18, wherein: The one or more curable monomers, oligomers or polymers include one or more acrylic monomers, acrylic oligomers or acrylic polymers.

20. The method according to claim 11, wherein: The inorganic particles include zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, or a mixture of two or more thereof.

21. The method according to claim 11, wherein: The first ink composition and the second ink composition are different.

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