Multicolor oled array for high-aperture displays

Abstract

Microcavity pixel design and fabrication methods for high-aperture-ratio organic light-emitting diode (OLED) arrays suitable for light field displays. This is achieved by laterally overlapping the middle electrode and the optical filler layer, reducing the lateral pitch. The OLED layers in this design have a uniform white OLED stack, allowing each layer to be deposited on the OLED array, simplifying the fabrication process. The optical path length of each sub-pixel optical microcavity is optimized by the thickness of the optical filler layer, allowing the white OLED stack to remain uniform, reducing the fabrication complexity.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Patent Application US17 / 378,300, filed July 16, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to a patterned design and manufacturing method for organic light-emitting diode (OLED) devices with high aperture suitable for light field displays. Background Technology

[0004] Light field displays offer multiple views, allowing users to receive a separate view in each eye. While current displays of this type offer an interesting viewing experience, truly captivating light field displays require very high pixel densities, very small angular distances between views, and wide viewing angles. Users are expected to experience smooth transitions between viewing areas while maintaining independent and perceptible views from adjacent ones. A fundamental requirement for achieving these viewing parameters is controlling the output characteristics of the emission source. Organic light-emitting diodes (OLEDs) bound within microcavities can control the spectral bandwidth and output angle of the generated light.

[0005] One method for controlling the output characteristics of light is the use of microcavities. A microcavity is formed between two mirrors or reflective surfaces, which can be, for example, a metal anode, a metal cathode, or a layered stack of non-absorbing materials, and can be a distributed Bragg reflector (DBR). Mirrors are used to reflect light within a certain wavelength range while typically preserving the physical properties of the incident light. The two main design variables affecting the output characteristics of the microcavity are the reflectivity of the top and bottom surfaces (i.e., the opposing mirrors) and the optical path length Λ. The wavelength of the light output by this OLED structure depends in part on the optical path length of the microcavity. The optical path length can be manipulated by adjusting the thickness and / or number of layers constituting the microcavity.

[0006] When manufacturing OLEDs of suitable size for light field displays, challenges arise in achieving the thickness required to deposit individual organic layers to realize the desired light path length for each color. One challenge in manufacturing OLEDs suitable for light field displays is achieving high aperture ratios of pixels smaller than 10 μm using existing manufacturing capabilities. The aperture ratio of a pixel is the ratio of the emitting area of ​​a pixel to the total area of ​​the display. A high aperture ratio can be achieved by maximizing the emitting area of ​​each pixel on the display. This reduces gaps in the display area, thereby improving the image quality of the light field display. Achieving a high aperture ratio is particularly challenging when manufacturing high-resolution displays with small pixel sizes.

[0007] US Patent Application Publication US2021 / 0057670 by Wong et al. describes a light-emitting OLED pixel array. The disclosed pixels use multiple transparent or substantially transparent dielectric layers on each anode. The thickness of the dielectric layers is designed to optimize the emission of light of the desired color for that pixel. A white OLED layer is formed in a single deposition step of the OLED array, and the lateral spacing between each anode results in a reduced aperture ratio.

[0008] U.S. Patent 10,790,473 to Park et al. describes a design for an OLED device with a high aperture ratio. The high aperture ratio is achieved by first connecting the reflective electrode and the transparent electrode of the anode at the corner of the sub-pixel region. Each sub-pixel has a microcavity structure, thereby minimizing the pixel-confining layer between sub-pixels. The spacing between sub-pixels is not preferred for light field displays because the luminescent area of ​​the display is not maximized.

[0009] High aperture ratios are preferred for near-eye displays, such as virtual reality (VR) displays, augmented reality (AR) displays, microdisplays, and light field displays. There remains a need for methods to design and fabricate micron-sized OLED pixel arrays with high aperture ratios suitable for the high display resolutions of light field displays.

[0010] The purpose of providing this background information is to convince the applicant that information potentially relevant to the present invention is known. It is not necessary to acknowledge, nor should it be construed, that any of the foregoing information constitutes prior art to the present invention. Summary of the Invention

[0011] One object of this disclosure is to provide an optical microcavity pixel device including an organic light-emitting diode (OLED) and a photolithographic patterning method that realizes micrometer-sized pixels that, when patterned in an array, achieve an aperture ratio greater than 70%. Another object of this disclosure is to provide an OLED array patterning method capable of producing a light field display with a resolution greater than 1,000 ppi (pixels per inch). The optical microcavity pixel array includes a distributed Bragg reflector (DBR) on a substrate and two or more sub-pixels, each sub-pixel including a translucent or fully transparent electrode and a series of translucent or fully transparent optical filler layers. Another object of the invention is to provide an optical microcavity pixel design structure in which translucent or fully transparent electrodes disposed on the DBR have lateral overlap to reduce lateral spacing, thereby improving the aperture ratio of the light field display. Limiting, reducing, or eliminating the lateral spacing between colored electrodes can be achieved using a series of layered translucent or fully transparent filler layers inserted between overlapping electrodes of a first color and a second color, a second color and a third color, a first color and a third color, or any combination thereof. The filler layer thickness is designed to adjust the optical cavity of each pixel, thereby determining the color generated by the optical microcavity pixel device. Another object of this disclosure is to provide a method for reducing the complexity of the fabrication process for high-aperture OLED arrays.

[0012] In one aspect, an organic light-emitting diode (OLED) device is provided, comprising: a substrate; a distributed Bragg reflector (DBR) located on the substrate; a first color electrode located on the DBR and defining a first color microcavity, the first color electrode being connected to the substrate through a first via; a first optical filler layer located on the DBR and adjacent to the first color electrode; a second optical filler layer located on the first optical filler layer and partially overlapping the first color electrode in an overlapping region; a second color electrode located on the second optical filler layer and defining a second color microcavity, the second color electrode being connected to the substrate through a second via; a white organic light-emitting diode (OLED) stack located above the first and second color electrodes; and a top electrode located above the white OLED stack.

[0013] In one embodiment, the second color electrode partially overlaps with the first color electrode.

[0014] In another embodiment, the first color microcavity has a first color optical path length passing through the first color electrode between the DBR and the top electrode, and the second color microcavity has a second color optical path length passing through the second color electrode between the DBR and the top electrode.

[0015] In another embodiment, the first color optical path length and the second first color optical path length are adjusted to provide the desired first color pixels and second color pixels, respectively.

[0016] In another embodiment, the first optical filler layer and the second optical filler layer comprise a transparent polymer.

[0017] In another embodiment, the first optical filler layer and the second optical filler layer comprise a transparent inorganic dielectric.

[0018] In another embodiment, the device further includes a pixel defining layer that insulates the first color electrode from the second color electrode.

[0019] In another embodiment, the pixel defining layer comprises one or more of an inorganic insulating dielectric and an organic material.

[0020] In another embodiment, the substrate is a thin-film transistor (TFT) substrate.

[0021] In another embodiment, the device further includes a second DBR on top of the top electrode.

[0022] In another embodiment, the top electrode is the cathode and the bottom electrode is the anode.

[0023] In another embodiment, the top electrode is the anode and the bottom electrode is the cathode.

[0024] In another embodiment, the device further includes: a third optical filler layer located above the second color electrode and below the white OLED stack, which is located on the first optical filler layer and defines a third color microcavity; a fourth optical filler layer located on the third optical filler layer and partially overlapping the second color electrode; and a third color electrode located on the fourth optical filler layer and partially overlapping the second color electrode, the third color electrode being connected to the substrate through a third via.

[0025] In another aspect, a method for fabricating a multicolor microcavity organic light-emitting diode (OLED) array is provided, the method comprising: depositing a distributed Bragg reflector (DBR) on a substrate; depositing a first color electrode on the DBR, the first color electrode defining a first color microcavity, the first color electrode being connected to the substrate through a first via; depositing a first optical filler layer on the DBR adjacent to the first color electrode; depositing a second optical filler layer on the first optical filler layer, the second optical filler layer partially overlapping the first color electrode in an overlapping region; depositing a second color electrode on the second optical filler layer, the second color electrode defining a second color microcavity, the second color electrode being connected to the substrate through a second via; depositing a stack of white organic light-emitting diodes (OLEDs) on the first color electrode and the second color electrode; and depositing a top electrode on the white OLED stack.

[0026] In an implementation of this method, white OLED stacks are deposited over the entire OLED array.

[0027] In another embodiment of the method, thermal evaporation, spin coating, or inkjet printing is used to deposit the white OLED stack.

[0028] In another embodiment of the method, thermal evaporation or sputtering is used to deposit the top electrode.

[0029] In another embodiment, the method further includes depositing a pixel-defining layer that insulates the first color electrode from the second color electrode.

[0030] In another embodiment of the method, sputtering, spin coating, thermal evaporation, chemical vapor deposition, atomic layer deposition, or spin casting are used to deposit the pixel-defining layer.

[0031] In another embodiment, the method further includes depositing a second DBR on the top electrode.

[0032] In another embodiment of the method, sputtering, thermal evaporation, or spin coating are used to deposit the first color electrode, the second color electrode, and the top electrode.

[0033] In another embodiment of the method, sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition is used to deposit the first optical filler layer and the second optical filler layer.

[0034] In another embodiment of the method, sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition is used to deposit the DBR.

[0035] In another embodiment, the method further includes: prior to depositing the white OLED stack: depositing a third optical filler layer selected for a third color on top of the first optical filler layer, the third optical filler layer overlapping the first color electrode; depositing a fourth optical filler layer selected for a third color on top of the third optical filler layer, the fourth optical filler layer overlapping the second color electrode; and depositing a series of third color electrodes on the fourth optical filler layer. Attached Figure Description

[0036] These and other features of the invention will become more apparent in the following detailed description with reference to the accompanying drawings.

[0037] Figure 1A An embodiment of a dual-color optical microcavity organic light-emitting diode (OLED) array according to the present disclosure is shown in cross-sectional view.

[0038] Figure 1B As shown Figure 1AAn enlarged view of the monochrome optical microcavity OLED device described in the image.

[0039] Figure 1C As shown Figure 1A An enlarged view of the described dual-color optical microcavity OLED device.

[0040] Figure 2 An alternative embodiment of a dual-color optical microcavity OLED array including a pixel definition layer (PDL) according to this disclosure is shown.

[0041] Figure 3A An alternative embodiment of a dual-color optical microcavity OLED array including an additional DBR deposited on the cathode is shown according to this disclosure.

[0042] Figure 3B As shown Figure 3A An enlarged view of the dual-color optical microcavity OLED device described in the image.

[0043] Figure 4 An embodiment of a cross-section of a three-color optical microcavity OLED array according to the present disclosure is shown.

[0044] Figure 5 An alternative embodiment of a three-color optical microcavity OLED array including PDL according to the present disclosure is shown.

[0045] Figure 6 An alternative embodiment of a tricolor optical microcavity OLED array including an additional DBR deposited on the cathode is shown according to this disclosure.

[0046] Figure 7 An embodiment of the optical path from a TFT substrate to the emission of a dual-color optical microcavity OLED array according to this disclosure is shown.

[0047] Figure 8 An embodiment of the optical path from a TFT substrate to the emission of a three-color optical microcavity OLED array according to this disclosure is shown.

[0048] Figure 9 A top view of an embodiment of light emission from a three-color optical microcavity OLED array according to the present disclosure is shown.

[0049] Figure 10A Step 1 of the proposed dual-color OLED array patterning process for depositing DBR is shown.

[0050] Figure 10B Step 2 of the proposed dual-color OLED array patterning process for forming through-holes through the first color electrode of the DBR is shown.

[0051] Figure 10CStep 3 of the proposed dual-color OLED array patterning process for depositing the first color electrode is shown.

[0052] Figure 10D Step 4 of the proposed dual-color OLED array patterning process for depositing photoresist is shown.

[0053] Figure 10E Step 5 of the proposed dual-color OLED array patterning process for photolithography is shown, which partially exposes the implementation to UV light, thereby partially removing the photoresist by etching.

[0054] Figure 10F Step 6 of the proposed patterning process for depositing the first optical filler layer in a dual-color OLED array is shown.

[0055] Figure 10G The proposed dual-color OLED array patterning process for photolithography is shown in step 7, which strips off the remaining photoresist to remove the first optical filler layer deposited on the photoresist.

[0056] Figure 10H A top view of step 7 of the proposed dual-color OLED array patterning process is shown.

[0057] Figure 10I Step 8 of the proposed patterning process for depositing a second optical filler layer in a dual-color OLED array is shown.

[0058] Figure 10J The diagram illustrates step 9 of the proposed dual-color OLED array patterning process, for forming a via through the DBR, the first optical filler layer, and the second optical filler layer for a second color electrode.

[0059] Figure 10K Step 10 of the proposed dual-color OLED array patterning process for depositing a second color electrode is shown.

[0060] Figure 10L A top view of step 10 of the proposed dual-color OLED array patterning process is shown.

[0061] Figure 10M Step 11 of the proposed dual-color OLED array patterning process for depositing white OLED stacks is shown.

[0062] Figure 10N Step 12 of the proposed dual-color OLED array patterning process is shown, which is used to deposit a cathode as a top reflective surface to form an optical microcavity for the OLED array.

[0063] Figure 11AStep 1 of the proposed three-color OLED array patterning process for depositing DBR is shown.

[0064] Figure 11B Step 2 of the proposed tricolor OLED array patterning process for forming a through-hole through the first color electrode of the DBR is shown.

[0065] Figure 11C Step 3 of the proposed tricolor OLED array patterning process for depositing the first color electrode is shown.

[0066] Figure 11D Step 4 of the proposed three-color OLED array patterning process for depositing photoresist is shown.

[0067] Figure 11E Step 5 of the proposed three-color OLED array patterning process for photolithography is shown, which partially exposes the implementation to UV light, thereby partially removing the photoresist by etching.

[0068] Figure 11F Step 6 of the proposed patterning process for depositing the first optical filler layer in a tricolor OLED array is shown.

[0069] Figure 11G The proposed three-color OLED array patterning process for photolithography is shown in step 7, which strips off the remaining photoresist to remove the first optical filler layer deposited on the photoresist.

[0070] Figure 11H A top view of step 7 of the proposed tricolor OLED array patterning process is shown.

[0071] Figure 11I Step 8 of the proposed patterning process for depositing a second optical filler layer in a tricolor OLED array is shown.

[0072] Figure 11J The diagram illustrates step 9 of the proposed three-color OLED array patterning process, which forms a via through the DBR, the first optical filler layer, and the second optical filler layer for the second color electrode.

[0073] Figure 11K Step 10 of the proposed tricolor OLED array patterning process for depositing the second color electrode is shown.

[0074] Figure 11L A top view of step 10 of the proposed tricolor OLED array patterning process is shown.

[0075] Figure 11MStep 11 of the proposed three-color OLED array patterning process for depositing photoresist is shown.

[0076] Figure 11N The proposed three-color OLED array patterning process for photolithography is shown in step 12, which partially exposes the implementation to UV light, thereby partially removing the photoresist by etching.

[0077] Figure 11O Step 13 of the proposed patterning process for depositing a third optical filler layer in a tricolor OLED array is shown.

[0078] Figure 11P The proposed three-color OLED array patterning process for photolithography is shown in step 14, which strips off the remaining photoresist to remove the third optical filler layer deposited on the photoresist.

[0079] Figure 11Q Step 15 of the proposed patterning process for depositing a fourth optical filler layer in a tricolor OLED array is shown.

[0080] Figure 11R The diagram illustrates step 16 of the proposed tri-color OLED array patterning process, which forms a via through the DBR, the first optical filler layer, the third optical filler layer, and the fourth optical filler layer for the third color electrode.

[0081] Figure 11S Step 17 of the proposed tricolor OLED array patterning process for depositing a third color electrode is shown.

[0082] Figure 11T A top view of step 17 of the proposed tricolor OLED array patterning process is shown.

[0083] Figure 11U Step 18 of the proposed tricolor OLED array patterning process for depositing white OLED stacks is shown.

[0084] Figure 11V Step 19 of the proposed tricolor OLED array patterning process is shown, which is used to deposit a cathode as a top reflective surface to form an optical microcavity for the OLED device. Detailed Implementation

[0085] definition

[0086] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0087] When used in conjunction with the term "including," the word "a" or "one" can mean "one," but it also aligns with the meanings of "one or more," "at least one," and "one or more."

[0088] As used herein, the terms “comprising,” “having,” “including,” and “containing,” and their grammatical variations, are inclusive or open-ended and do not exclude additional, unlisted elements and / or method steps. When used herein in conjunction with compositions, apparatuses, articles, systems, uses, or methods, the term “consistently of” indicates that additional elements and / or method steps may be present, but these additions do not materially affect how the said composition, apparatus, article, system, method, or use operates. Compositions, apparatuses, articles, systems, uses, or methods described herein that include certain elements and / or steps may substantially include those elements and / or steps in some embodiments, and include those elements and / or steps in other embodiments, whether or not those embodiments are specifically mentioned.

[0089] As used herein, the term “about” refers to a change of approximately + / - 10% from a given value. It should be understood that such a change is always included in any given value provided herein, whether or not it is specifically mentioned.

[0090] Unless otherwise stated herein, the description of ranges in this document is intended to convey the range and the individual values ​​falling within that range to the same bit values ​​as the numbers used to represent that range.

[0091] Any use of example or exemplary language, such as “such as,” “exemplary embodiment,” “illustrative embodiment,” and “e.g.,” is intended to illustrate or represent aspects, embodiments, variations, elements, or features relevant to this invention and is not intended to limit the scope of the invention.

[0092] As used herein, the terms “connected” and “connected” refer to any direct or indirect physical association between elements or features of this disclosure. These terms may be understood to mean elements or features that partially or wholly contain, are attached to, coupled to, arranged thereon, joined together, connected, operatively associated with, etc., even if there are other elements or features between the elements or features described as connected.

[0093] As used in this article, the term "OLED" refers to Organic Light Emitting Diode, an optoelectronic device that emits light when an external voltage is applied. OLEDs have an electroluminescent layer or an organic material or substance that emits light in response to an electric current. OLEDs can be divided into two main categories: those made of small organic molecules and those made of organic polymers. Without being bound by theory, when an electric current is applied, the anode injects holes into the organic layer, and the cathode injects electrons into the organic layer. The injected holes and electrons migrate towards the electrodes with opposite charges. When electrons and holes are localized on the same molecule, excitons are formed, which are localized electron-hole pairs with excited energy states. When the excitons relax through a light emission mechanism, light is emitted. Types of OLEDs include, but are not limited to, Active Matrix OLEDs (AMOLEDs) and Passive Matrix OLEDs (PMOLEDs). AMOLEDs have a complete cathode layer, an organic molecular layer, and an anode layer. The anode layer has thin-film transistor (TFT) planes parallel to it to form a matrix. This allows each pixel to be switched on or off as needed to form an image. Therefore, pixels can be turned off whenever a pixel or a black image on the display is not needed, thus reducing the energy required to illuminate the display. This is the lowest power consumption type of OLED, with a faster refresh rate, making it suitable for video. PMOLED has a similar composition to AMOLED, but the cathode and anode lines are arranged at right angles. Electrical control is achieved through the anode and cathode lines, activating the pixels at the intersection to produce light. The background of a PMOLED display is always black, and the color displayed when a pixel is activated is a predetermined color. PMOLED pixels are fixed to a single color, making them unsuitable for dynamic images or displays. OLEDs can be top-emitting or bottom-emitting. Top-emitting OLEDs have an opaque or reflective substrate. If the emitted light passes through a transparent or translucent bottom electrode and substrate, the OLED is bottom-emitting. Top-emitting OLEDs are generally more suitable for active-matrix applications because they can be more easily integrated with opaque transistor backplanes.

[0094] As used herein, the term "DBR" refers to a distributed Bragg reflector. A distributed Bragg reflector is an optical mirror composed of different dielectric layers with different refractive indices arranged in an alternating sequence.

[0095] As used herein, the term "optical path length," denoted by Λ, refers to the distance between two points (P1, P2), taking into account the refractive index (n) of the material through which light propagates. In an exemplary OLED device, the medium through which light propagates may include one or more semi-transparent or transparent intermediate electrodes and other layers, as well as layers comprising a white OLED stack. The optical path length is defined as a function:

[0096]

[0097] As used in this paper, the term "light field" refers to a function describing the amount of light flowing through a point in space in each direction. A light field can be expressed as an emissivity as a function of the position and direction of light in free space, ideally without occlusion. Light fields can be generated, for example, through various rendering processes, or captured from a light field camera or an array of light field cameras.

[0098] As used herein, the term "light field display" is a device for reconstructing a light field. In one embodiment, a light field can be reconstructed from a finite number of light field radiance samples input to the light field display device. The luminance samples typically represent the red, green, and blue (RGB) color components. For reconstruction in a light field display, the light field can also be understood as a mapping from four-dimensional space to a single RGB color, where the four dimensions include the display's vertical and horizontal dimensions, and two dimensions describing the directional components of the light field. In one embodiment, the light field can be defined as the following function:

[0099] LF∶(x,y,u,v)→(r,g,b)

[0100] For a fixed x f ,y f ,LF(x f ,y f (x, u, v) represents a two-dimensional (2D) image called an "elemental image", where the elemental image is derived from a fixed point x. f ,y f An oriented image of the light field at a location. When multiple element images are connected side-by-side, the resulting image is called an "integral image." An integral image can be understood as the entire light field required for a light field display.

[0101] As used in this article, the term "aperture ratio" in describing optical displays refers to the ratio of the luminescent area to the total pixel area, defined as a function:

[0102]

[0103] As used in this article, the term "pixel" refers to the light source and light emission mechanism used to create a display.

[0104] As used herein, the term "subpixel" refers to a structure consisting of light-emitting devices housed within an optical microcavity.

[0105] As used herein, the term “electrode” refers to a conductor through which electricity enters or leaves an object, substance, or area.

[0106] As used herein, the term "cathode" refers to a negatively charged electrode through which electrons enter an electrical device.

[0107] As used in this article, the term "anode" refers to a positively charged electrode through which electrons leave an electrical device.

[0108] As used herein, the term “patterning” refers to the technique of transferring patterns onto a target material.

[0109] As used in this article, the term “wavelength” is a measure of the distance between two identical peaks (high points) or troughs (low points) in a wave, which is a repeating pattern of traveling energy (such as light or sound).

[0110] This paper describes the design and method of a microcavity organic light-emitting diode (OLED) for tuning a micrometer-scale multicolor optical microcavity OLED array. Light field displays require a pixel density of at least 25,000 pixels per inch (ppi), with each pixel being less than 20 μm. Most preferably, light field displays with high display resolution have a pixel density greater than 5,000 ppi. Achieving a high aperture ratio at these resolutions can be achieved by maximizing the luminescent area of ​​each subpixel and minimizing the subpixel spacing. This invention provides an optical microcavity pixel device comprising an organic light-emitting diode (OLED) and a photolithographic patterning method that realizes micrometer-scale pixels that, when patterned into an array, achieve an aperture ratio greater than 70%, suitable for light field displays with resolutions greater than 1,000 ppi. This can be achieved by patterning a transparent or semi-transparent optical filler layer and intermediate electrodes to laterally overlap other intermediate electrodes in the OLED array to reduce lateral spacing and increase the aperture ratio of the resulting OLED array. This laterally overlapping design allows designers to optimize the optical characteristics of each OLED device and the aperture ratio of the entire OLED array. While the industry defines a high aperture ratio for micrometer-sized pixel displays as 70%, this design enables displays to achieve close to or approximately 100% aperture ratios, creating high-quality displays suitable for light field displays and other applications. Methods for designing and manufacturing OLED device arrays that emit light, including but not limited to yellow, red, green, or blue light, are also disclosed.

[0111] Various features of the invention will become apparent from the following detailed description and the accompanying drawings. The design parameters, methods, construction, and use of the optical microcavity OLED design process and structure disclosed herein are described with reference to various representative embodiments, which are not intended to limit the scope of the invention described and claimed herein. Those skilled in the art will understand that other variations, embodiments, and implementations of the invention not disclosed herein may exist and can be practiced based on the teachings of this disclosure without departing from the scope of the invention.

[0112] Each OLED in this device includes an electrode configured to be connected to a substrate, an optical microcavity including a distributed Bragg reflector (DBR), and a cathode. The optical microcavity is operatively associated or connected to one or more reflective surfaces to substantially collimate, manipulate, or tune the light. At least one reflective surface is a light-propagating reflective surface connected to the optical microcavity to propagate light out of the optical microcavity. This invention provides individually addressable red, green, and blue (RGB) subpixels. The subpixel sizes described here range from nanometers to several micrometers. As described herein, the DBR consists of alternating stacks of dielectric material of a specific thickness, ensuring that the optical path length is one-quarter of the design wavelength and suitable for use with OLEDs of any color. The highest reflectivity can be obtained when the layer thickness is selected such that the optical path length of each layer is one-quarter of the resonant wavelength. Since the optical path length of each layer is λ Bragg / 4, all reflections will be in phase and additive, and the transmittance will decrease exponentially as a function of the mirror thickness. At wavelengths longer or shorter than the stopband, reflections begin to be out-of phase and additive, thus reducing the total reflection. This gives a broadband high-reflectivity region centered on the Bragg wavelength, called the stopband, with oscillating sidelobes on both sides. DBRs are typically composed of pairs of two different dielectric layers with different refractive indices, but can also be composed of multiple dielectric materials or other transparent materials with a contrast ratio of n, as long as the optical path length of each layer is λ. Bragg / 4 is sufficient. Multi-layered mirrors consist of alternating layers of substantially non-absorbent material of appropriately selected thickness. Typically, each layer is [thickness value missing]. Advantageously, λ is chosen to roughly correspond to the center wavelength of the EML emission spectrum, for example, 500-550 nm. Such mirrors are well known. The reflectivity of a mirror depends in a known manner on the number of layer pairs, the layer thickness, and the refractive index of the materials used. Exemplary material pairs in the visible light wavelength region are Si3N4, SiO2, and TiO2.

[0113] Figure 1AAn embodiment of a cross-section of the dual-color optical microcavity OLED array described herein is shown, having two OLED devices of a first color and one OLED device of a second color. The OLED array shown includes a DBR 12 deposited on a substrate 10. In this embodiment, the substrate 10 is a TFT substrate, which is the device forming the basic structure of the OLED embodiment, providing electrical control to switch each pixel or sub-pixels to their on or off state as needed. The TFT comprises multiple layers, including a metal gate electrode, a gate insulator, a semiconductor layer, and source / drain electrodes deposited on the substrate. The TFT substrate preferably also has a planarization layer on which the OLED material is deposited. The DBR 12 includes a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. The number of high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78 can be configured to any integer. In the illustrated embodiment, the DBR 12 can serve as the first reflective surface of the optical microcavity for each OLED device in the OLED array.

[0114] Before each electrode (hereinafter referred to herein as first color electrodes 14A, 14B) in a series of electrodes for the first color OLED device array is deposited on the DBR 12, vias for each first color OLED (hereinafter referred to herein as first color vias 16A, 16B) are dry etched through the DBR 12. This provides electrical connections from the substrate 10 to the first color electrodes 14A, 14B. The first color vias 16A, 16B can be etched using etching techniques such as reactive ion etching, anodic plasma etching, magnetically enhanced reactive ion etching, triode reactive ion etching, or transport-coupled plasma etching. In this embodiment, a dry etching method, such as reactive ion etching, is preferred. After etching the first color vias 16A, 16B through the DBR 12, the first color electrodes 14A, 14B are deposited on the DBR 12 using a shadow mask. For each second color OLED device in the OLED array, a first optical filler layer 18 is directly patterned on the DBR 12, between the first color electrodes 14A, 14B, using photolithography. Patterning can be achieved, for example, by using a series of post-processing steps to chemically etch the transferred pattern into the transferred material or to allow new material to be deposited within the transferred material. Then, for each second-color OLED device in the OLED array, a second optical filler layer 20 is patterned over the first optical filler layer 18 by a shadow mask or by photolithography, covering the first optical filler layer 18. The second optical filler layer 20 can overlap with the first color electrodes 14A, 14B to form overlapping regions 80A, 80B. The overlapping regions 80A, 80B provide tolerances to mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between the OLED devices on the substrate 10. The optical filler layer is designed to be transparent to visible light and electrically insulating. The optical filler layer serves as an electrical insulating layer to prevent crosstalk between the first color electrodes 14A, 14B and the second color electrode 22 in the overlapping regions 80A, 80B.

[0115] Before the second color electrode 22 is deposited on the second optical filler layer 20, a second color via 24 is etched through the second optical filler layer 20, the first optical filler layer 18, and the DBR 12 using reactive ion etching dry etching. The second color via 24 provides an electrical connection from the substrate 10 to the second color electrode 22. The second color electrode 22 is then patterned on the second optical filler layer 20 using a shadow mask, preferably wherein the width of the second color electrode 22 is the same as the width of the second optical filler layer 20. For a dual-color OLED array, a layer of white OLED stack 26 is then deposited over the entire OLED array. In a tri-color OLED array, a third optical filler layer, a fourth optical filler layer, a third color via, and a third color electrode are deposited for the third color, followed by the deposition of the white OLED stack 26. The uniformly deposited OLED stack emits white light, and for each color's optical microcavity, the optical path length is adjusted to obtain a specific color. A cathode 28 is then deposited on the white OLED stack 26 using, for example, a thermal evaporation deposition method. In this embodiment, the cathode 28 is a reflective material, the thickness of which results in a transmittance greater than 0%, and is used to form the optical microcavity of each OLED device.

[0116] In this embodiment, substrate 10 includes non-conductive components forming the substrate of the OLED device and conductive components supplying power to each electrode. One embodiment may be a thin-film transistor (TFT) substrate composed of one or more semiconductor materials, a gate insulator, and a substrate. Semiconductor materials may include, for example, hydrogenated amorphous silicon, polycrystalline silicon, amorphous oxide semiconductors, cadmium selenide, zinc oxide, organic materials such as pentacene, poly(3-hexylthiophene), poly(3-alkylthiophene), and poly(3-octylthiophene), or transparent electrodes such as indium zinc oxide (IZO) or indium tin oxide (ITO). Indium tin oxide (ITO) is typically an oxygen-saturated composition formulated with 74% In, 18% O2, and 8% Sn by weight. ITO is also commonly used as an anode material in OLED structures because it has suitable conductivity, near-transparent and colorless optical properties, and can be deposited using well-established methods. ITO can also be used to construct the anode layer in the OLED device according to the present invention. The gate insulator can be a metal passivation material with a transparent insulator, such as SiO2 and Si3N4, or an organic material, such as polymethyl methacrylate. The substrate can also be a non-conductive material, such as glass. The DBR 12 includes alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78, which can be composed of TiO2 and SiO2. The first color electrodes 14A, 14B and the second color electrode 22 can be translucent or transparent conductive materials, such as ITO, conductive polymers such as doped polyaniline, or thin layers (between 5 and 35 nm, preferably less than 10 nm) of metal or alloy, or carbon-based materials such as graphene. Transparent conductive materials (e.g., ITO) are preferred due to their high transmittance (80-85%) and low reflectance and absorbance.

[0117] The first optical filler layer 18 and the second optical filler layer 20 can be, for example, a transparent polymer, such as polyimide, or an inorganic transparent dielectric with various refractive index values, such as Al2O3, SiO2, or Si3N4. The first optical filler layer 18 and the second optical filler layer 20 can be composed of the same or different materials. The optical filler layers 18 and 20 can be deposited by, for example, sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition. A preferred deposition method is sputtering, which allows the designer to precisely adjust the layer thickness during deposition. The thickness of the optical filler layers and the materials constituting them are designed to adjust the optical path length for each specific color. Preferred materials for the optical filler layers have a refractive index similar to that of the bottom electrode. For example, ITO can be used for the second color electrode 22, and Al2O3 can be used for both the first optical filler layer 18 and the second optical filler layer 20. The white OLED stack 26 includes thin film layers of organic materials, which typically include one or more of an organic hole injection layer (HIL), an organic hole transport layer (HTL), an emitter layer (EML), an organic electron transport layer (ETL), and an organic electron injection layer. A series of layers in a white OLED stack are designed to emit white light. The individual color of each OLED device is achieved by adjusting the optical path length of each optical microcavity. Each layer of the white OLED stack 26 can be deposited by thermal evaporation, spin casting, or inkjet printing. For this embodiment, a preferred method for depositing the white OLED stack 26 is thermal evaporation. The cathode 28 can be a reflective metal with a reflectivity greater than 90%, such as aluminum, cadmium, or silver. This embodiment illustrates a conventional OLED configuration in which the bottom first color electrodes 14A, 14B and the second color electrode 22 below the white OLED stack 26 are anodes, and the top electrode above the white OLED stack 26 is the cathode 28. The described microcavity OLED here has substantially reflective top and bottom surfaces and substantially transparent intermediate layers, which together create the optical path length required to resonate within the optical microcavity to produce the desired color. In this configuration, where the DBR 12 is the bottom reflective surface and the cathode 28 is the top reflective surface, the cathode 28 being slightly less reflective than the DBR 12, thereby allowing light generated in the optical microcavity to be emitted through the top of the OLED array. In another arrangement, the OLED array can be configured as an array of inverted OLED devices, wherein the bottom electrode deposited beneath the white OLED stack 26 is a completely transparent cathode, and the top electrode above the white OLED stack is a reflective anode. The OLED array described herein can also be configured as an array of bottom-emitting OLED devices, wherein the reflectivity of the bottom electrode, DBR 12, and substrate 10 is slightly lower than that of the top electrode, thereby allowing emitted light to pass through the substrate 10. The OLED array can also be configured to consist of any combination of inverted or non-inverted and top- or bottom-emitting OLEDs.

[0118] In an optical microcavity, the optical path length for each color is equal to the peak wavelength of that color divided by two and multiplied by a positive integer.

[0119] so:

[0120]

[0121] in:

[0122] Λ Cx The length of the light path for the color is m, which is an integer.

[0123] λ Cx It is the peak wavelength of the color.

[0124] Each element constituting the optical microcavity has an optical path length determined by the refractive index and thickness of the material. The total optical path length for each color can be determined by the optical path length of each of the following elements constituting the optical microcavity: DBR 12, electrodes 14, 22, optical filler layers 18, 20, white OLED stack 26, and cathode 28. Since DBR 12 and cathode 28 are reflective surfaces forming the boundaries of the optical microcavity, the penetration depth into DBR 12 and cathode 28 is considered in addition to the refractive index and thickness. In this embodiment, DBR 12 and cathode 28 are homogeneous, and the white OLED stack 26 is designed to emit white light across the entire OLED array. The optical path length for each color includes the penetration depth of DBR 12 and the penetration depth of cathode 28. These penetration depths are incorporated into the design considerations and are constant across the entire OLED array. DBR 12 and cathode 28 are present but are not used to adjust the optical path length to emit a specific color.

[0125] so:

[0126] Λ C1 =Λ e1 +Λ OLED +(Λ 阴极 +Λ DBR )

[0127] Λ C2 =Λ f1 +Λ f2 +Λ e2 +Λ OLED +(Λ 阴极 +Λ DBR )

[0128] The optical path length Λ of each first-color OLED device in the OLED array C1 The optical path lengths referred to herein as the first color 30A, 30B are determined by the optical path length of the first electrode of each first color OLED device in the OLED array, and are referred to herein as the optical path length of the first electrode (Λ).e1 The optical path length (Λ) of the stacked 34A, 34B, and white OLEDs OLED 32. The optical path length Λ of each second-color OLED device in the OLED array. C2 In this article, the optical path length (Λ) of the second color is referred to as the optical path length of the second color. C2 )36, the optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the second optical filler layer (Λ) f2 40. Optical path length of the second color electrode (Λ) e2 )42 and the optical path length of white OLED stacking (Λ OLED The sum of Λ32 is determined. Since the optical path length of each element in the optical microcavity is determined by the element's thickness and refractive index, adjusting the thickness of specific elements within the optical microcavity allows designers to optimize the optical path length for the desired color. When white OLED stacks are deposited across 26 spans of the OLED array, the optical path length (Λ) of the white OLED stack is... OLED )32 can be designed to adjust the optical path length (Λ) of the first color. C1 )30A, 30B, this can be achieved by optimizing the thickness of the white OLED stack 26. Specifically, the optical path length of the first color (Λ C1 The optical path length (Λ) should be approximately equal to the peak wavelength of the first color divided by two and multiplied by an integer. Since the optical path length of the white OLED stack 32 is uniform across the entire OLED array, the thickness of the second optical filler layer 20 can also be considered when designing the optical path length (Λ) of the second optical filler layer. f2 )40, to produce the optical path length (Λ) required for the second color C2 36. It is advantageous to optimize the optical path lengths of the first colors 30A and 30B using the optical path length of the white OLED stack 32, and to optimize the optical path length of the second color 36 using the optical path length of the second optical filler layer 40, because the white OLED stack 26 can be uniform. The uniform white OLED stack 26 can then be deposited on the entire OLED array, thereby simplifying manufacturing.

[0129] Figure 1B As shown Figure 1A The image shows an enlarged view of the monochromatic optical microcavity OLED device described herein. The OLED device includes a DBR 12 deposited on a substrate 10, which may be a TFT substrate. The DBR 12 includes a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. It should be noted that... Figure 1BThe number of pairs of high-refractive-index dielectric layer 76 and low-refractive-index dielectric layer 78 shown is three, comprising six layers, but the DBR can be composed of any integer number of layers. This composition allows the DBR 12 to act as the first reflective surface of the optical microcavity for each OLED device in the OLED array. The first color electrode 14 is deposited on the DBR 12 using a shadow mask. The layers constituting the white OLED stack 26 are then individually deposited on the entire OLED array. Each layer of the white OLED stack 26 can be deposited by, for example, thermal evaporation, spin casting, and inkjet printing, and is preferably deposited by thermal evaporation. For this embodiment, the white OLED stack 26 may include one or more of the following layers: organic hole injection layer (HIL) 84, organic hole transport layer (HTL) 86, emission layer (EML) 88, organic electron transport layer (ETL) 90, and organic electron injection layer (EIL) 92. In some configurations, the white OLED stack 26 may include a single EML 88, in which emission molecules of a specific color are combined to produce white light. In an alternative configuration, the white OLED stack 26 may include multiple EMLs 88, which may be referred to as tandem or stacked white OLEDs. In a tandem white OLED, white light is generated by all emitting EMLs 88 in the white OLED stack 26. In a tandem OLED configuration, additional charge-generating layers may be deposited to serve as additional injection layers and artificial metal electrodes. The combination of organic layers in the white OLED stack 26 is designed to emit white light, while each optical microcavity modulates the optical path length of various elements to achieve a specific color. A cathode 28 is then deposited on the white OLED stack 26 using, for example, thermal evaporation. In this embodiment, the cathode 28 is a reflective material and is used to form the optical microcavity of each OLED device.

[0130] Figure 1C As shown Figure 1AAn enlarged view of the dual-color optical microcavity OLED device is shown. The OLED device includes a DBR 12 deposited on a substrate 10. In this embodiment, the substrate 10 is a TFT substrate. The DBR 12 includes a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. The number of high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78 can be configured to any integer. This composition allows the DBR 12 to act as the first reflective surface of the optical microcavity for each OLED device in the OLED array. A first color electrode 14 is deposited on the DBR 12 using a shadow mask. For each second-color OLED device in the OLED array, a first optical filler layer 18 is directly patterned on the DBR 12, adjacent to the first color electrode 14, using photolithography. Then, for each second-color OLED device in the OLED array, a second optical filler layer 20 is patterned on the first optical filler layer 18, covering the entire first optical filler layer 18, and can overlap with the first color electrode 14 to form an overlap region 80. The overlapping region 80 mitigates alignment errors during manufacturing, thereby increasing the display's aperture ratio by reducing the lateral spacing between OLED devices on substrate 10. The second color electrode 22 is patterned on the second optical filler layer 20 using a shadow mask; preferably, the width of the second color electrode 22 is the same as the width of the second optical filler layer 20. Although only the first and second microcavities are shown here, it should be understood that the OLED array includes a plurality of first color microcavities with first electrodes and a plurality of second color microcavities with second electrodes. It should also be understood that the OLED array typically includes a plurality of microcavities of three different colors to provide red, green, and blue emission.

[0131] The layers constituting the white OLED stack 26 are then individually deposited on the entire OLED array. Each layer of the white OLED stack 26 can be deposited by thermal evaporation, spin casting, or inkjet printing. For this embodiment, thermal evaporation is preferred. For this embodiment, the organic layers constituting the white OLED stack 26 are deposited on the first and second color electrodes 14, 22 in the following order: organic hole injection layer (HIL) 84, organic hole transport layer (HTL) 86, emission layer (EML) 88, organic electron transport layer (ETL) 90, and organic electron injection layer (EIL) 92. The white OLED stack 26 may also include one or more of each type of organic layer. The organic layers of the white OLED stack 26 are designed together to emit white light, while each optical microcavity adjusts the optical path length of various elements to achieve a specific color. A cathode 28 is then deposited on the white OLED stack 26 using, for example, thermal evaporation. In this embodiment, the cathode 28 is a reflective material and is used to form the optical microcavity of each OLED device.

[0132] Figure 2 An alternative embodiment of a dual-color optical microcavity OLED array including a pixel definition layer (PDL) 44 according to this disclosure is shown. The cross-section shows two OLED devices of the first color and one OLED device of the second color. The OLED array includes a DBR 12 deposited on a substrate 10. In this embodiment, the substrate 10 is a TFT substrate, which is the device forming the basic structure of this embodiment. The DBR 12 includes a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. Before the first color electrodes 14A, 14B are deposited on the DBR 12, first color vias 16A, 16B are dry-etched through the DBR 12 to provide electrical connections from the substrate 10 to the first color electrodes 14A, 14B. In this embodiment, the preferred dry etching method is reactive ion etching. The first color electrodes 14A, 14B are then patterned on the DBR 12 using a shadow mask. A first optical filler layer 18 is patterned on the DBR 12 between the first color electrodes 14A, 14B using photolithography. A second optical filler layer 20 is deposited on and completely covers the first optical filler layer 18, and may overlap with the first color electrodes 14A and 14B to form overlapping regions 80A and 80B. The second optical filler layer may be patterned using a shadow mask or photolithography. The overlapping regions 80A and 80B provide tolerances to mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10.

[0133] Prior to depositing the second color electrode 22, reactive ion etching is used to dry-etch the second color via 24 through the optical filler layers 20, 18 and DBR 12 to provide electrical connection to the substrate 10. The second color electrode 22 is patterned on the second optical filler layer 20 with a shadow mask, wherein the width of the second color electrode 22 is equal to the width of the second optical filler layer 20. In this embodiment, an optional PDL 44 is patterned with a shadow mask such that it covers the areas of the second color electrode 22 and the second optical filler layer 20 suspended above the adjacent first color electrodes 14A, 14B. The PDL 44 prevents electrical short circuits between the first color electrodes 14A, 14B and the second color electrode 22, thereby reducing crosstalk on the OLED array. Crosstalk typically refers to light leakage from one pixel to another, which interferes with image quality, resulting in loss of contrast, loss of depth resolution, viewer discomfort, and image repetition. The PDL 44 can be deposited by, for example, sputtering, spin coating, thermal evaporation, chemical vapor deposition, atomic layer deposition, or spin casting. Optional PDL 44 can be composed of inorganic materials such as insulating dielectrics (e.g., Al2O3, Si3N4, or SiO2) or organic materials such as photosensitive polyimide. In a tri-color OLED device, the PDL layer can also connect the third color electrode to the second color electrode. The layers constituting the white OLED stack 26 are deposited over the entire OLED array. A cathode 28 is then deposited on the white OLED stack 26 by thermal evaporation. In this embodiment, the cathode 28 is a reflective material and is therefore used to form the optical microcavity of each OLED device.

[0134] The light path length of the first color (Λ) C1 )30A, 30B are determined by the optical path length (Λ) of the first electrode e1 The optical path length (Λ) of the stacked 34A, 34B, and white OLEDs OLED )32 is determined. The optical path length of the second color (Λ) C2 )36 The optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the second optical filler layer (Λ) f2 40. Optical path length of the second color electrode (Λ) e2 )42 and the optical path length of white OLED stacking (Λ OLED )32 is determined. Since the optical path length of each element in the optical microcavity is determined by the element's thickness and refractive index, adjusting the thickness of a specific element within the optical microcavity allows the designer to adjust the optical path length for the desired color. When a white OLED stack 26 is deposited on an OLED array; the optical path length (Λ) of the white OLED stack OLED )32 can be designed to adjust the optical path length (Λ) of the first color. C1)30A, 30B, this can be achieved by optimizing the thickness of the white OLED stack 26. Since the optical path length 32 of the white OLED stack is uniform across the entire OLED array, the optical path length (Λ) of the second optical filler layer f2 )40 can be designed by the thickness of the second optical filler layer 20 to produce the optical path length (Λ) required for the second color. C2 36.

[0135] Because the white OLED stack 26 can be uniform, it is advantageous to optimize the optical path lengths 30A and 30B of the first color using the optical path length of the white OLED stack 32, and to optimize the optical path length 36 of the second color using the optical path length of the second optical filler layer 40. The uniform white OLED stack 26 can then be deposited on the entire OLED array, thereby simplifying manufacturing.

[0136] Figure 3A An alternative embodiment of a dual-color optical microcavity OLED array with a second DBR 12B deposited on a cathode 28 is shown. The cross-section shows two OLED devices for the first color and one OLED device for the second color. The OLED array includes a first DBR 12A deposited on a substrate 10. In this embodiment, the substrate 10 is a TFT substrate, which forms the basic structure of the device in this embodiment. The first DBR 12A has a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. Before the first color electrodes 14A, 14B are deposited on the first DBR 12A, first color vias 16A, 16B are dry-etched through the first DBR 12A to provide electrical connections from the substrate 10 to the first color electrodes 14A, 14B. In a preferred embodiment, reactive ion etching is used to create the vias. The first color electrodes 14A, 14B are then patterned onto the first DBR 12A using a shadow mask. The first optical filler layer 18 is then patterned on the first DBR 12A between the first color electrodes 14A and 14B using photolithography. A second optical filler layer 20 is then deposited such that it completely covers the first optical filler layer 18 and preferably overlaps with the first color electrodes 14A and 14B to form overlapping regions 80A and 80B. The second optical filler layer 20 can be patterned using a shadow mask or photolithography. The overlapping regions 80A and 80B provide tolerances to mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10.

[0137] Prior to depositing the second color electrode 22, reactive ion etching is used to dry etch the second color via 24 through the optical filler layers 20, 18 and the first DBR 12A to provide electrical connection to the substrate 10. The second color electrode 22 is patterned on the second optical filler layer 20 using a shadow mask, wherein the width of the second color electrode 22 is approximately equal to the width of the second optical filler layer 20. A layer including the white OLED stack 26 is then deposited over the entire OLED array. A cathode 28 is then deposited on the white OLED stack 26 by thermal evaporation. In this embodiment, an additional DBR 12B is deposited on top of the cathode 28. The second DBR 12B has a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. The cathode 28 is made of a translucent or transparent material, and the DBR 12B is used to form the optical microcavity of each OLED device.

[0138] Each element comprising the optical microcavity has an optical path length determined by the refractive index and thickness of the material. The total optical path length for each color can be determined by the optical path length of each of the following elements comprising the optical microcavity: first DBR 12A, first electrodes 14A, 14B, second electrode 22, optical filler layers 18, 20, white OLED stack 26, cathode 28, and second DBR 12B. Since the first DBR 12A and second DBR 12B are reflective surfaces forming the boundaries of the optical microcavity, the penetration depth into DBR 12A, 12B is considered in addition to the refractive index and thickness. In this embodiment, DBR 12A, 12B, and cathode 28 are homogeneous, and the white OLED stack 26 is designed to emit white light for the entire OLED array. The optical path length for each color includes the penetration depth of the first DBR 12A, the penetration depth of the second DBR 12B, and the optical path length of the cathode 28. These penetration depths and corresponding optical path lengths are incorporated into the design considerations but are constant throughout the OLED array. The first DBR12A, the second DBR 12B, and the cathode 28 are not used to adjust the optical path length to emit a specific color.

[0139] so:

[0140] Λ C1 =Λ e1 +Λ OLED +(Λ 阴极 +Λ DBR A +Λ DBR B )

[0141] Λ C2 =Λ f1 +Λ f2 +Λ e2 +Λ OLED +(Λ阴极 +Λ DBR A +Λ DBR B )

[0142] The light path length of the first color (Λ) C1 )30A, 30B are determined by the optical path length (Λ) of the first electrode e1 The optical path length (Λ) of the stacked 34A, 34B, and white OLEDs OLED )32 is determined. The optical path length of the second color (Λ) C2 )36 The optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the second optical filler layer (Λ) f2 40. Optical path length of the second color electrode (Λ) e2 )42 and the optical path length of white OLED stacking (Λ OLED The sum of Λ32 is determined. Since the optical path length of each element in the optical microcavity is determined by the element's thickness and refractive index, designers can adjust the optical path length for the desired color by adjusting the thickness of specific elements within the optical microcavity. When white OLED stacks are deposited across 26 spans of the OLED array, the optical path length (Λ) of the white OLED stack is... OLED )32 can be designed to adjust the optical path length (Λ) of the first color. C1 30A, 30B, this can be achieved by optimizing the thickness of the white OLED stack 26. Since the optical path length 32 of the white OLED stack is uniform across the entire OLED array, the optical path length (Λ) of the second optical filler layer... f2 )40 can also be designed by the thickness of the second optical filler layer 20 to produce the optical path length (Λ) required for the second color. C2 36. Because the white OLED stack 26 can be uniform across the entire OLED optical microcavity array, it is advantageous to optimize the optical path lengths 30A and 30B of the first color using the optical path length 32 of the white OLED stack, and to optimize the optical path length 36 of the second color using the optical path length 40 of the second optical filler layer. The uniform white OLED stack 26 can also be deposited across the entire OLED array, thereby simplifying manufacturing.

[0143] Figure 3B As shown Figure 3AAn enlarged view of the dual-color optical microcavity OLED device described herein. The OLED device includes a first DBR 12A deposited on a substrate 10, preferably a TFT substrate. The first DBR 12A is composed of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. The number of high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78 can be any integer number of layers, of which three pairs are shown in this configuration, comprising six layers. In this embodiment, the first DBR 12A serves as the first reflective surface of the optical microcavity for each OLED device in the OLED array. A first color electrode 14 is deposited on the first DBR 12A using a shadow mask. For each second-color OLED device in the OLED array, a first optical filler layer 18 is directly patterned on the first DBR 12A, adjacent to the first color electrode 14, using photolithography. Then, for each second-color OLED device in the OLED array, the second optical filler layer 20 is patterned on the first optical filler layer 18 by a shadow mask or photolithography, covering the entire first optical filler layer 18 and overlapping with the first color electrode 14 to form an overlap region 80. The overlap region 80 mitigates alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between the OLED devices on the substrate 10. The second color electrode 22 is patterned on the second optical filler layer 20 using a shadow mask, preferably wherein the width of the second color electrode 22 is the same as the width of the second optical filler layer 20.

[0144] Then, the layers constituting the white OLED stack 26 are individually deposited on the entire OLED array. Each layer of the white OLED stack 26 can be deposited by, for example, thermal evaporation, spin casting, or inkjet printing. For this embodiment, thermal evaporation is preferred. The organic layers comprising the white OLED stack 26 are then deposited on the first and second color electrodes 14, 22 in the following order: organic hole injection layer (HIL) 84, organic hole transport layer (HTL) 86, emission layer (EML) 88, organic electron transport layer (ETL) 90, and organic electron injection layer (EIL) 92. The white OLED stack 26 may include one or more of each type of organic layer. The organic layers are designed to emit white light, while each optical microcavity adjusts the optical path length of various elements to achieve a specific color. A cathode 28 is then deposited on the white OLED stack 26 using, for example, thermal evaporation. In this embodiment, the cathode 28 is made of a translucent or transparent material, and a second DBR 12B is deposited on the cathode 28. The second DBR 12B comprises a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. The number of high-refractive-index dielectric layers 76 and 78 in the second DBR 12B can also be configured to any integer. This configuration allows the second DBR 12B to act as the top reflective surface of the optical microcavity for each OLED device in the OLED array.

[0145] Figure 4 A cross-sectional embodiment of a three-color optical microcavity OLED array according to the present disclosure is shown. The OLED array includes a DBR 12 deposited on a substrate 10. The cross-section shows two OLED devices of the first color and individual OLED devices of each of the second and third colors. In this embodiment, the substrate 10 is a TFT substrate, which is the device forming the basic structure of the OLED array. The DBR 12 includes a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78, wherein the number of high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78 can be any integer. In this composition, the DBR 12 is the first reflective surface of the optical microcavity of each OLED device in the OLED array.

[0146] Before depositing the first color electrodes 14A and 14B for the first color OLED device array on the DBR 12, first color vias 16A and 16B are dry etched through the DBR 12 to provide electrical connections from the substrate 10 to the first color electrodes 14A and 14B. The vias can be etched by, for example, reactive ion etching, anodic plasma etching, magnetically enhanced reactive ion etching, triode reactive ion etching, and transport-coupled plasma etching. A preferred dry etching method for constructing the vias is reactive ion etching. After etching the first color vias 16A and 16B through the DBR 12, the first color electrodes 14A and 14B are patterned on the DBR 12 using a shadow mask. Then, a first optical filler layer 18 is patterned directly on the DBR 12 between the first color electrodes 14A and 14B of each second color OLED device in the OLED array using photolithography. Then, a second optical filler layer 20 is deposited on the first optical filler layer 18, partially covering the first optical filler layer 18, and may overlap with the first color electrode 14A to form an overlap region 80A. The second optical filler layer 20 may be patterned using a shadow mask or photolithography. The overlap region 80A provides tolerances to mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10.

[0147] Before the second color electrode 22 is deposited on the second optical filler layer 20, a second color via 24 is dry-etched through the second optical filler layer 20, the first optical filler layer 18, and the DBR 12 using reactive ion etching. The second color via 24 provides an electrical connection from the substrate 10 to the second color electrode 22. The second color electrode 22 is then patterned on the second optical filler layer 20 using a shadow mask, preferably wherein the width of the second color electrode 22 is the same as the width of the second optical filler layer 20. Then, for each third color OLED device in the OLED array, a third optical filler layer 58 is patterned on the first optical filler layer 18 adjacent to the second optical filler layer 20 using photolithography, and the third optical filler layer 58 may overlap with the first color electrode 14B to form an overlap region 80C. For each third color OLED device in the OLED array, a fourth optical filler layer 60 is deposited on the third optical filler layer 58, and the fourth optical filler layer 60 may overlap with the second color electrode 22 to form an overlap region 80D. The fourth optical filler layer 60 can be patterned using a shadow mask or photolithography. The overlapping regions 80C and 80D can reduce alignment errors during manufacturing and increase the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10.

[0148] Before depositing the third color electrode 62 onto the fourth optical filler layer 60, a third color via 64 is preferably dry-etched through the fourth optical filler layer 60, the third optical filler layer 58, the first optical filler layer 18, and the DBR 12 using reactive ion etching. The third color via 64 provides an electrical connection from the substrate 10 to the third color electrode 62. The third color electrode 62 is then patterned on the fourth optical filler layer 60 using a shadow mask, preferably wherein the width of the third color electrode 62 is the same as the width of the fourth optical filler layer 60. A layer comprising a white OLED stack 26 is then deposited over the entire OLED array. A cathode 28 is then deposited on the white OLED stack 26 using, for example, thermal evaporation. In this embodiment, the cathode 28 is a reflective material and is therefore used to form the optical microcavity of each OLED device.

[0149] In this embodiment, substrate 10 may be a thin-film transistor (TFT) substrate composed of semiconductor material, gate insulator, and substrate. Semiconductor material may include, for example, hydrogenated amorphous silicon, polycrystalline silicon, amorphous oxide semiconductor, cadmium selenide, zinc oxide; organic materials, such as pentacene, poly(3-hexylthiophene), poly(3-alkylthiophene), and poly(3-octylthiophene); or transparent electrodes, such as ITO. The gate insulator may be a metal passivated with a transparent insulator such as SiO2 and Si3N4 or an organic material such as polymethyl methacrylate. The substrate may also be a non-conductive material, such as glass. DBR 12 includes alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric material layers 78. Electrodes 14A, 14B, 22, and 62 may be translucent or transparent conductive materials, such as ITO, conductive polymers, such as doped polyaniline, or thin layers of metals or alloys (5 to 35 nm, preferably less than 10 nm), and carbon-based materials, such as graphene. Transparent conductive materials such as ITO are preferred for use in this disclosure due to their high transmittance (80-85%) and low reflectance and absorbance. Optical filler layers 18, 20, 58, and 60 may comprise transparent polymers such as polyimide, or inorganic transparent dielectrics with various refractive index values ​​such as Al2O3, SiO2, or Si3N4. Optical filler layers 18, 20, 58, and 60 may be deposited by sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition. Preferred materials for the optical filler layers have a refractive index similar to that of the bottom electrode; for example, if ITO is a preferred material for the second color electrode 22 and the third color electrode 62, then Al2O3 is a preferred material for the optical filler layer. The preferred deposition method is sputtering, which allows the designer to precisely adjust the layer thickness during deposition. The white OLED stack 26 includes organic material thin film layers, which typically include one or more of an organic hole injection layer (HIL), an organic hole transport layer (HTL), an emitter layer (EML), an organic electron transport layer (ETL), and an organic electron injection layer. This series of OLED layers is designed to emit white light. Each layer of the white OLED stack 26 can be deposited via thermal evaporation, spin casting, and inkjet printing. For this embodiment, thermal evaporation is the preferred method. The individual color of each OLED device is achieved by modulating the optical path length of each optical microcavity. The cathode 28 can be a reflective metal with a reflectivity greater than 90%, such as aluminum, cadmium, or silver. This embodiment illustrates a conventional OLED configuration in which the bottom electrodes 14A, 14B, 22, 62 below the white OLED stack 26 are anodes, while the electrodes above the white OLED stack 26 are cathodes 28. The invention can also be configured as an inverted OLED device array, where the bottom electrode deposited before the white OLED stack 26 is the cathode 28, and the top electrode above the white OLED stack 26 is the anode.This disclosure can also be configured as an array of bottom-emitting OLED devices, wherein the bottom electrode, DBR 12, and substrate 10 are semi-transparent or transparent, and light is emitted through substrate 10. The disclosed embodiments can be configured to be inverted or non-inverted and any combination of top or bottom emitting.

[0150] Each element constituting the optical microcavity has an optical path length determined by the refractive index and thickness of the material. The total optical path length for each color can be determined by the optical path length of each of the following elements constituting the optical microcavity: DBR 12, electrodes 14, 22, 62, optical filler layers 18, 20, 58, 60, white OLED stack 26, and cathode 28. Since DBR 12 and cathode 28 are reflective surfaces forming the boundaries of the optical microcavity, the penetration depth into DBR 12 and cathode 28 is considered in addition to the refractive index and thickness. In this embodiment, DBR 12 and cathode 28 are homogeneous, and the white OLED stack 26 is designed to emit white light across the entire OLED array. The optical path length for each color includes the penetration depth of DBR 12 and the penetration depth of cathode 28. These penetration depths are incorporated into the design considerations but are constant across the entire OLED array. The DBR 12 and cathode 28 shown are not used to adjust the optical path length to emit a specific color.

[0151] so:

[0152] Λ C1 =Λ e1 +Λ OLED +(Λ 阴极 +Λ DBR )

[0153] Λ C2 =Λ f1 +Λ f2 +Λ e2 +Λ OLED +(Λ 阴极 +Λ DBR )

[0154] Λ C3 =Λ f1 +Λ f3 +Λ f4 +Λ e3 +Λ OLED +(Λ 阴极 +Λ DBR )

[0155] The optical path length Λ of each first-color OLED device in the OLED array C1 In this document, the optical path lengths 30A and 30B, referred to as the first color, are determined by the optical path length (Λ) of the first electrode. e1The optical path length (Λ) of the stacked 34A, 34B, and white OLEDs OLED The optical path length of the first electrode of each first-color OLED device in a 32-element OLED array is determined. The optical path length Λ of each second-color OLED device in the OLED array is also determined. C2 In this article, the optical path length (Λ) of the second color is referred to as the optical path length of the second color. C2 )36, the optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the second optical filler layer (Λ) f2 40. Optical path length of the second color electrode (Λ) e2 42. and the optical path length (Λ) of the white OLED stack. OLED The sum of 32 is determined. The optical path length Λ of each third-color OLED device in the OLED array is... C3 This is referred to in this article as the optical path length of the third color (Λ). C3 )66, the optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the third optical filler layer (Λ) f3 68. Optical path length of the fourth optical filler layer (Λ) f4 70. Optical path length of the third color electrode (Λ) e3 )72 and the optical path length (Λ) of white OLED stacking OLED The sum of 32 is determined.

[0156] Since the optical path length of each element in an optical microcavity is determined by the element's thickness and refractive index, adjusting the thickness of a specific element within the optical microcavity allows designers to optimize the optical path length for the desired color. When white OLEDs are stacked in a 26-span OLED array, the optical path length (Λ) of the white OLED stack is... OLED )32 can be designed to adjust the optical path length (Λ) of the first color. C1 )30A, 30B, this can be achieved by optimizing the thickness of the white OLED stack 26. Specifically, the optical path length of the first color (Λ C1 30A and 30B should be approximately equal to the peak wavelength of the first color divided by two and multiplied by an integer. Since the optical path length of the white OLED stack 32 is uniform across the entire OLED array, the thickness of the second optical filler layer 20 can also be considered when designing the optical path length (Λ) of the second optical filler layer. f2 )40, to adjust the required optical path length (Λ) for the second color. C2 36. Similarly, the thickness of the fourth optical filler layer 62 can be considered when designing the optical path length (Λ) of the fourth optical filler layer. f4 )70 to adjust the required optical path length (Λ) for the third color C366. Because the white OLED stack 26 can be uniform, it is advantageous to optimize the optical path lengths 30A and 30B of the first color using the optical path lengths of the white OLED stack 32, and to optimize the optical path lengths 36 of the second color and 66 of the third color using the optical path lengths 40 and 70 of the optical filler layers. The uniform white OLED stack 26 can then be deposited across the entire OLED array, thereby simplifying manufacturing.

[0157] Figure 5An alternative embodiment of a three-color optical microcavity OLED array including a pixel definition layer (PDL) 44 according to this disclosure is shown. This cross-section shows two OLED devices for the first color and a single OLED device for each of the second and third colors. The OLED array includes a DBR 12 deposited on a substrate 10. In this embodiment, the substrate 10 is a TFT substrate, which is the device forming the basic structure of this embodiment. The DBR 12 includes a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. Before depositing the first color electrodes 14A, 14B, first color vias 16A, 16B are dry-etched through the DBR 12 to provide electrical connections to the substrate 10. In this embodiment, the preferred dry-etching method is reactive ion etching. The first color electrodes 14A, 14B are patterned on the DBR 12 using a shadow mask. A first optical filler layer 18 is patterned on the DBR 12 between the first color electrodes 14A, 14B using photolithography. A second optical filler layer 20 is deposited on and partially covers the first optical filler layer 18, and may overlap with the first color electrode 14A to form an overlap region 80A. The second optical filler layer 20 may be patterned using a shadow mask or photolithography. The overlap region 80A provides tolerances to mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10. A second color via 24 is then dry-etched through the optical filler layers 18, 20, and DBR 12 using reactive ion etching to provide electrical connection between the second color electrode 22 and the substrate 10. The second color electrode 22 is patterned on the second optical filler layer 20 using a shadow mask, wherein the width of the second color electrode 22 is equal to the width of the second optical filler layer 20. A third optical filler layer 58 is patterned on the first optical filler layer 18 adjacent to the second optical filler layer 20 using photolithography, and the third optical filler layer 58 may overlap with the first color electrode 14B to form an overlap region 80C. A fourth optical filler layer 60 is deposited on the third optical filler layer 58 and can overlap with the second color electrode 22 to form an overlap region 80D. The fourth optical filler layer 60 can be patterned using a shadow mask or photolithography. The overlap regions 80C, 80D can mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10. The third color via 64 is then dry-etched through the optical filler layers 58, 60 and the DBR 12 using reactive ion etching to provide electrical connection to the substrate 10. The third color electrode 62 is patterned on the fourth optical filler layer 60 using a shadow mask, wherein the width of the third color electrode 62 is equal to the width of the fourth optical filler layer 60.In this embodiment, an optional PDL 44 is patterned using a shadow mask such that it covers the regions of the second and third color electrodes 22, 62 and the optical filler layers 20, 60, 58 suspended above the respective adjacent first color electrodes 14A, 14B and second color electrode 22. The PDL 44 is then deposited between the first color electrode 14A and the second color electrode 22, between the second color electrode 22 and the third color electrode 62, and between the third color electrode 62 and the first color electrode 14B. The PDL 44 can reduce crosstalk on the OLED array and prevent electrical short circuits. A layer comprising a white OLED stack 26 is then deposited over the entire OLED array. A cathode 28 is then deposited on the white OLED stack 26 using, for example, thermal evaporation. In this embodiment, the cathode 28 is a reflective material and forms part of the optical microcavity of each OLED device.

[0158] Each element constituting the optical microcavity has an optical path length determined by the refractive index and thickness of the material. The total optical path length for each color can be determined by the optical path length of each of the following elements constituting the optical microcavity: DBR 12, electrodes 14, 22, 62, optical filler layers 18, 20, 58, 60, white OLED stack 26, and cathode 28. Since DBR 12 and cathode 28 are reflective surfaces forming the boundaries of the optical microcavity, the penetration depth into DBR 12 and cathode 28 is considered in addition to the refractive index and thickness. In this embodiment, DBR 12 and cathode 28 are homogeneous, and the white OLED stack 26 is designed to emit white light across the entire OLED array. The optical path length for each color includes the penetration depth of DBR 12 and the penetration depth of cathode 28. These penetration depths are incorporated into the design considerations but are constant across the entire OLED array. DBR 12 and cathode 28 are not used to adjust the optical path length to emit a specific color.

[0159] so:

[0160] Λ C1 =Λ e1 +Λ OLED +(Λ 阴极 +Λ DBR )

[0161] Λ C2 =Λ f1 +Λ f2 +Λ e2 +Λ OLED +(Λ 阴极 +Λ DBR )

[0162] Λ C3 =Λ f1 +Λ f3 +Λ f4+Λ e3 +Λ OLED +(Λ 阴极 +Λ DBR )

[0163] The light path length of the first color (Λ) C1 )30A, 30B are determined by the optical path length (Λ) of the first electrode e1 The optical path length (Λ) of the stacked 34A, 34B, and white OLEDs OLED )32 is determined. The optical path length of the second color (Λ) C2 )36 The optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the second optical filler layer (Λ) f2 40. Optical path length of the second color electrode (Λ) e2 )42 and the optical path length of white OLED stacking (Λ OLED The sum of 32 determines the path length of the third color (Λ). C3 )66 is determined by the sum of the following: the optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the third optical filler layer (Λ) f3 68. Optical path length of the fourth optical filler layer (Λ) f4 70. Optical path length of the third color electrode (Λ) e3 )72 and the optical path length (Λ) of white OLED stacking OLED 32.

[0164] Since the optical path length of each element in an optical microcavity is determined by the element's thickness and refractive index, adjusting the thickness of a specific element within the optical microcavity allows designers to optimize the optical path length for the desired color. When white OLED stacks 26 are deposited on an OLED array; the optical path length (Λ) of the white OLED stacks... OLED )32 can be designed to adjust the optical path length (Λ) of the first color. C1 )30A, 30B, this can be achieved by optimizing the thickness of the white OLED stack 26. Since the optical path length 32 of the white OLED stack is uniform across the entire OLED array, the optical path length (Λ) of the second optical filler layer f2 )40 can be designed by adjusting the thickness of the second optical filler layer 20 to adjust the optical path length (Λ) required for the second color. C2 36. Similarly, the optical path length (Λ) of the fourth optical filler layer f4 )70 can be designed by adjusting the thickness of the fourth optical filler layer 60 to adjust the required optical path length (Λ) for the third color. C3 66.

[0165] Because the white OLED stack 26 can be uniform, it is advantageous to optimize the optical path lengths 30A and 30B of the first color using the optical path length 32 of the white OLED stack, and to optimize the optical path lengths 36 and 66 of the second and third colors using the optical path lengths 40 and 70 of the optical filler layers. The uniform white OLED stack 26 can then be deposited on the entire OLED array, thereby simplifying manufacturing.

[0166] Figure 6An alternative embodiment of a three-color optical microcavity OLED array according to this disclosure is shown, comprising a second DBR 12B deposited on a cathode 28. This cross-section shows two OLED devices for the first color and a single OLED device for each of the second and third colors. The OLED array includes a first DBR 12A deposited on a substrate 10. In this embodiment, the substrate 10 is a TFT substrate forming the basic structure of this embodiment. The first DBR 12A includes a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. For each first color electrode 14A, 14B, first color vias 16A, 16B are dry-etched through the first DBR 12A to provide electrical connection to the substrate 10. The first color electrodes 14A, 14B are then patterned on the first DBR 12A using a shadow mask. A first optical filler layer 18 is then patterned between the first color electrodes 14A, 14B and on the first DBR 12A using photolithography. Next, a second optical filler layer 20 is deposited on and partially covers the first optical filler layer 18, and may overlap with the first color electrode 14A to form an overlap region 80A. The second optical filler layer 20 can then be patterned using a shadow mask or photolithography. The overlap region 80A provides tolerances to mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10. A second color via 24 is then etched through the first optical filler layer 18, the second optical filler layer 20, and the first DBR 12A to provide electrical connection between the second color electrode 22 and the substrate 10. The second color electrode 22 is then patterned on the second optical filler layer 20 using a shadow mask, wherein the width of the second color electrode 22 is equal to the width of the second optical filler layer 20. Then, a third optical filler layer 58 is patterned on the first optical filler layer 18 adjacent to the second optical filler layer 20 using photolithography, and the third optical filler layer 58 can overlap with the first color electrode 14B to form an overlap region 80C. A fourth optical filler layer 60 is then deposited on the third optical filler layer 58 and can overlap with the second color electrode 22 to form an overlap region 80D. The fourth optical filler layer 60 can be patterned using a shadow mask or photolithography. The overlap regions 80C, 80D can mitigate alignment errors during manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10. Then, a third color via 64 is dry-etched through the optical filler layers 58, 60 and the first DBR 12A to provide electrical connection to the substrate 10. A third color electrode 62 is then patterned on the fourth optical filler layer 60 using a shadow mask, wherein the width of the third color electrode 62 is equal to the width of the fourth optical filler layer 60. A layer including the white OLED stack 26 is deposited over the entire OLED array.The cathode 28 is then deposited on the white OLED stack 26 using, for example, thermal evaporation. In this embodiment, a second DBR 12B is deposited on the cathode 28. The second DBR 12B comprises a series of alternating high-refractive-index dielectric layers 76 and low-refractive-index dielectric layers 78. The cathode 28 is made of a translucent or transparent material, and the second DBR 12B is used to form the optical microcavity of each OLED optical microcavity device.

[0167] Each element constituting the optical microcavity has an optical path length determined by the refractive index and thickness of the material. The total optical path length for each color can be determined by the optical path length of each of the following elements constituting the optical microcavity: the first DBR 12A, electrodes 14, 22, 62, optical filler layers 18, 20, 58, 60, white OLED stack 26, cathode 28, and second DBR 12B. Since the first DBR 12A and second DBR 12B are reflective surfaces forming the boundaries of the optical microcavity, the penetration depth into the DBRs 12A and 12B is considered in addition to the refractive index and thickness when calculating each optical path length. In this embodiment, the DBRs 12A, 12B, and cathode 28 are homogeneous, and the white OLED stack 26 is designed to emit white light for the entire OLED array. The optical path length for each color includes the penetration depth of the first DBR 12A, the penetration depth of the second DBR 12B, and the optical path length of the cathode 28. These penetration depths and corresponding optical path lengths are taken into account in the design, but remain constant throughout the OLED array. The first DBR 12A, the second DBR 12B, and the cathode 28 are not used to adjust the optical path length to emit a specific color.

[0168] so:

[0169] Λ C1 =Λ e1 +Λ OLED +(Λ 阴极 +Λ DBR A +Λ DBR B )

[0170] Λ C2 =Λ f1 +Λ f2 +Λ e2 +Λ OLED +(Λ 阴极 +Λ DBR A +Λ DBR B )

[0171] Λ C3 =Λ f1 +Λ f3 +Λf4 +Λ e3 +Λ OLED +(Λ 阴极 +Λ DBR A +Λ DBR B )

[0172] The light path length of the first color (Λ) C1 )30A, 30B are determined by the optical path length (Λ) of the first electrode e1 The optical path length (Λ) of the stacked 34A, 34B, and white OLEDs OLED )32 is determined. The optical path length of the second color (Λ) C2 )36 The optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the second optical filler layer (Λ) f2 40. Optical path length of the second color electrode (Λ) e2 )42 and the optical path length of white OLED stacking (Λ OLED The sum of 32 determines the path length of the third color (Λ). C3 )66 is determined by the sum of the following: the optical path length (Λ) of the first optical filler layer f1 38. Optical path length of the third optical filler layer (Λ) f3 68. Optical path length of the fourth optical filler layer (Λ) f4 70. Optical path length of the third color electrode (Λ) e3 )72, and the optical path length of the white OLED stack (Λ OLED 32.

[0173] Since the optical path length of each element in an optical microcavity is determined by the element's thickness and refractive index, adjusting the thickness of a specific element within the optical microcavity allows designers to optimize the optical path length for the desired color. When white OLED stacks 26 are deposited on an OLED array; the optical path length (Λ) of the white OLED stacks... OLED )32 can be designed to adjust the optical path length (Λ) of the first color. C1 )30A, 30B, this can be achieved by optimizing the thickness of the white OLED stack 26. Since the optical path length 32 of the white OLED stack is uniform across the entire OLED array, the optical path length (Λ) of the second optical filler layer f2 )40 can be designed by adjusting the thickness of the second optical filler layer 20 to adjust the optical path length (Λ) required for the second color. C2 36. Similarly, the optical path length (Λ) of the fourth optical filler layer f4 )70 can be designed by adjusting the thickness of the fourth optical filler layer 60 to adjust the required optical path length (Λ) for the third color.C3 66. Because the white OLED stack 26 can be uniform, it is advantageous to optimize the optical path lengths 30A and 30B of the first color using the optical path length 32 of the white OLED stack, and to optimize the optical path lengths 36 and 66 of the second and third colors using the optical path lengths 40 and 70 of the optical filler layers. The uniform white OLED stack 26 can then be deposited on the entire OLED array, thereby simplifying manufacturing.

[0174] Figure 7 An embodiment of the optical path from substrate 10 to a first color light emitter 50A, 50B and a second color light emitter 52 of a dual-color optical microcavity OLED array according to this disclosure is shown. Each sub-pixel in a series of sub-pixels of the first color OLED device array (hereinafter referred to as first color sub-pixels 46A, 46B) is the width of the light-emitting region of each first color OLED device, shown as first color light emitters 50A, 50B, respectively. Each sub-pixel in a series of sub-pixels of the second color OLED device array (hereinafter referred to as second color sub-pixels 48) is the width of the light-emitting region of each second color OLED device, shown as second color light emitter 52. Current originating from substrate 10 flows through first color vias 16A, 16B and second color vias 24, respectively, to first color electrodes 14A, 14B and second color electrodes 22, and then through the white OLED stack 26 to the cathode 28. Those skilled in the art will understand that the multiple layers including the white OLED stack 26 create the light-emitting region, wherein electrons give energy in the form of photons emitted as first color light emitters 50A, 50B and second color light emitters 52, respectively. The regions below the first color light emission 50A and 50B can be considered as separate optical microcavities for the first color. These microcavities are optimized to emit light of the first color. The region below the second color light emission 52 can be considered as separate optical microcavities for the second color. These microcavities are also optimized to emit light of the second color. The optical microcavities form regions where optical resonance occurs to generate and emit light of a specific color. The light is optimized for both the first and second colors through the design of the lengths of the corresponding optical microcavities created by the distance between the top of the DBR 12 and the bottom of the cathode 28. The white OLED stack 26 is also designed to create the optical microcavities required for the first color OLED device. The first optical filler layer 18 and the second optical filler layer 20 are transparent or translucent, thus creating the optical microcavity lengths required for the second color OLED device. The patterning of the first color electrodes 14A, 14B and the second color electrode 22 is designed to minimize the lateral spacing, thereby allowing the first color sub-pixels 46A, 46B and the second color sub-pixels 48 and their corresponding light-emitting areas 50A, 50B, 52 to fully utilize their light-emitting areas, thereby improving the aperture ratio of the light field display.

[0175] Figure 8 An embodiment of the optical path from substrate 10 to a three-color optical microcavity OLED array, comprising first color light emitters 50A, 50B, second color light emitters 52, and third color light emitters 56, according to the present disclosure, is illustrated. Each sub-pixel in a series of sub-pixels of the first color OLED device array (hereinafter referred to as first color sub-pixels 46A, 46B) is the width of the light-emitting region of each first color OLED device, shown as first color light emitters 50A, 50B. Each sub-pixel in a series of sub-pixels of the second color OLED device array (hereinafter referred to as second color sub-pixels 48) is the width of the light-emitting region of each second color OLED device, shown as second color light emitter 52. Each sub-pixel in a series of sub-pixels of the third color OLED device array (hereinafter referred to as third color sub-pixels 54) is the width of the light-emitting region of each third color OLED device, shown as third color light emitter 56. It should be understood that the three-color OLED array according to the present invention comprises a plurality of first color sub-pixels, second color sub-pixels, and third color sub-pixels. Current originating from substrate 10 flows through vias 16A, 16B, 24, and 64, reaching electrodes 14A, 14B, 22, and 62, and then through the white OLED stack 26 to the cathode 28. The layers including the white OLED stack 26 create light-emitting regions where electrons release energy as photons emitted as first-color light emission 50A, 50B, second-color light emission 52, and third-color light emission 56. The emitted light travels the length of the corresponding optical microcavities created by the distance between the top of the DBR 12 and the bottom of the cathode 28 for the first, second, and third colors, and the white OLED stack 26 is designed to create the desired optical microcavities for the first-color OLED device. The first optical filler layer 18 and the second optical filler layer 20 are transparent or translucent, thereby producing the desired optical microcavity length for the second-color OLED device. The first optical filler layer 18, the third optical filler layer 58, and the fourth optical filler layer 60 are transparent or translucent, thereby producing the desired optical microcavity length for the third-color OLED device. The patterning of the first color electrodes 14A, 14B, the second color electrode 22, and the third color electrode 62 minimizes the lateral spacing, allowing the first color sub-pixels 46A, 46B, the second color sub-pixel 48, and the third color sub-pixel 54, along with their corresponding light-emitting areas 50A, 50B, 52, and 56, to fully utilize the light-emitting area, thereby increasing the aperture ratio of the light field display.

[0176] Figure 9A top view of the light emission of a three-color optical microcavity OLED array with overlapping sub-pixels according to the present disclosure is shown. The overlapping patterning of the first color electrode, the second color electrode, and the third color electrode minimizes the lateral spacing and results in the overlap of the sub-pixels of the three colors and their corresponding light-emitting regions. This allows the OLED array to fully utilize the light-emitting area, thereby improving the aperture ratio of the light field display. As shown, the first color light emission 50, the second color light emission 52, and the third color light emission 56 overlap. Figure 9 The diagram shows a triangular triplet subpixel configuration, which is one possible configuration for the currently described tricolor OLED array.

[0177] The fabrication of optical microcavity OLED devices suitable for light field displays is inherently complex due to the pixel size required to achieve high aperture displays. Figure 10A -N illustrates a method for manufacturing a dual-color OLED array according to this disclosure.

[0178] Figure 10A The first step in the manufacturing process is illustrated, where DBR 12 is deposited on substrate 10. In this embodiment, substrate 10 is a TFT substrate, which is the device forming the basic structure of this embodiment. It should be understood that... Figure 10A The DBR 12 shown comprises alternating high-refractive-index dielectric layers and low-refractive-index dielectric layers. Each layer of the DBR 12 can be deposited by sputtering, thermal evaporation, chemical vapor deposition, and atomic layer deposition. The preferred deposition method for this embodiment is sputtering.

[0179] Figure 10B The diagram illustrates first color vias 16A and 16B etched through a DBR 12 to connect to a substrate 10. The vias can be etched using reactive ion etching, anodic plasma etching, magnetically enhanced reactive ion etching, triode reactive ion etching, and transport-coupled plasma etching. In this embodiment, reactive ion etching is the preferred dry etching method.

[0180] Figure 10CThe diagram shows first color electrodes 14A and 14B deposited on a DBR 12. First color vias 16A and 16B provide electrical connections between the first color electrodes 14A and 14B and the substrate 10. The electrodes can be patterned by sputtering, thermal evaporation, and spin coating. In this embodiment, sputtering is the preferred deposition method. A shadow mask can be used to deposit elements in a desired pattern, such as the first color electrodes 14A and 14B in this embodiment. A shadow mask is typically a microstructure or template used to precisely define device areas for various applications involving deposition, etching, or substrate fabrication. The shadow mask is designed with specific perforations that allow for precise patterning of the elements during the deposition process when placed on the substrate. Precision is particularly important when depositing micrometer-scale OLED devices because alignment or deposition errors can occur. This will result in suboptimal electrical and optical characteristics of the OLED device, thereby reducing the aperture ratio of the OLED array. A shadow mask is a tool used to pattern a substrate, wherein any suitable deposition method, such as sputtering, thermal evaporation and spin coating in this embodiment, can be used with a shadow mask to deposit the desired pattern of the first color electrodes 14A, 14B on the DBR 12.

[0181] Figure 10D -G illustrates a series of photolithography steps for patterning the first optical filler layer. Photolithography is a widely used manufacturing technique that uses photoresist and ultraviolet (UV) light to transfer a pattern onto a substrate through a photomask. The photomask can be, for example, a thin plate with submicron or nanoscale patterns, having opaque and transparent areas in the desired pattern, and preferably contains glass or fused silica. The photomask is used in conjunction with UV light to transfer the pattern from the mask onto the substrate using high-resolution photolithography. Photolithography is a process in which the top surface is first cleaned with solvents such as acetone, methanol, and isopropanol, followed by cleaning with deionized water. It should be noted that if the desired pixel size is larger than in this embodiment, a shadow mask can be used for any patterning step in this embodiment.

[0182] Figure 10DA cross-sectional view of an embodiment after the deposition of photoresist 74 is shown. Deposition can be achieved, for example, by spin coating. Photoresist 74 is deposited on a structure including a substrate 10 on which a DBR 12 is deposited, and first color electrodes 14A and 14B are stacked on the DBR 12 and connected to the substrate 10 through vias 16A and 16B, respectively. The structure with photoresist 74 is soft-baked at a temperature below about 110°C to remove solvent contents. A patterning step, such as using a photomask, is used, where the photomask is designed with a series of nanoscale opaque and transparent portions of a specific pattern, wherein the pattern can be transferred onto the top layer during the photolithography process. The photomask can be made of glass, fused silica, or other suitable materials. In this embodiment, the photomask is designed with opaque portions in the pattern of the first color electrodes 14A and 14B.

[0183] exist Figure 10EIn this process, the structure on the substrate 10 with a photomask is exposed to UV light. The UV light causes a chemical change, allowing the photoresist 74 to be removed by etching. During photolithography, the photoresist 74 in the area between the first electrodes 14A and 14B where the first optical filler layer needs to be applied is removed, exposing the DBR 12, while the photoresist above the first electrodes 14A and 14B with vias 16A and 16B remains intact. There are two types of photoresist: positive photoresist and negative photoresist. When a positive photoresist is exposed to UV light, it undergoes a chemical change, becoming soluble in etching, and after UV exposure, only the exposed portion of the photoresist is removed by etching. The unexposed portion of the photoresist remains insoluble. In negative photoresist, the exposed portion of the photoresist becomes insoluble in etching. In this embodiment, photoresist 74 is preferably a positive photoresist, which has been found to be easier to control during photolithography because it can maintain its size and pattern, has better etch resistance, and exhibits excellent resolution and thermal stability. However, it should be understood that negative photoresists can also be used. Etching removes the photoresist layer in the embodiment by: chemical etching, which may be referred to as developer etching; plasma etching; reactive ion etching; and ion beam milling. The photoresist material and etching process (which may include developer material) are specifically designed to work synergistically to create high-quality patterns without affecting other deposited materials in the embodiment. A mask or photomask controls the location of light (i.e., UV light used for photolithography) illuminating the wafer or substrate. A photomask may comprise an opaque plate with perforated or transparent areas that allow light to pass through at defined locations. The photomask material may comprise, for example, fused silica (quartz glass) with a coating pattern made of chromium. In some cases, the photomask will be further coated with polytetrafluoroethylene (PTFE) to help prevent static friction problems during contact photolithography. For positive photoresist, the photomask will have the desired pattern and the pattern will be transferred to the implementation through a photolithography process.

[0184] Figure 10FThe deposition of a first optical filler layer 18 over the entire OLED array is shown. The first optical filler layer 18 can be deposited on the DBR 12 and photoresist 74 by, for example, sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition, thereby protecting the first electrodes 14A, 14B and vias 16A, 16B. A preferred deposition method is sputtering, which allows the designer to precisely adjust the layer thickness during deposition. The substrate 10 and the layers thereon are then exposed to a stripping agent that removes the photoresist 74 and the first optical filler layer 18 deposited on the photoresist 74. The photoresist stripping agent interacts with, breaks down, and removes the photoresist 74, while the remaining layers already deposited on the substrate remain intact. Some examples of photoresist strippers are, for example: solvents such as acetone, NMP (1-methyl-2-pyrrolidone), dimethyl sulfoxide; alkaline media such as 2-3% potassium hydroxide (KOH) or sodium hydroxide (NaOH); hydrofluoroethers; commercially available strippers such as AZ 100, TechniStrip P1316, P1331, N1555; and combustion using O2 plasma.

[0185] Figure 10G The substrate 10 is shown after the removal of the remaining photoresist and the first optical filler layer 18 deposited on the photoresist. It should be noted that the entire photolithography process can be repeated to deposit all subsequent optical filler layers disclosed herein. The DBR 12, first electrodes 14A, 14B, and vias 16A, 16B remain intact on the substrate 10.

[0186] Figure 10H This shows the result after the photolithography step is completed. Figure 10G A top view of the embodiment is shown. A pattern of the first color electrodes 14A, 14B and the first optical filler layer 18 across the OLED array is shown, and in particular, how the patterning eliminates the spacing between OLED devices is shown.

[0187] Figure 10I A second optical filler layer 20 is shown, deposited on and covering the entire first optical filler layer 18 and partially overlapping the first color electrodes 14A and 14B to form overlapping regions 80A and 80B. The second optical filler layer 20 can be deposited by, for example, sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition. A preferred deposition method is sputtering, which allows the designer to precisely adjust the layer thickness during deposition. The overlapping regions 80A and 80B provide tolerances to mitigate alignment errors in manufacturing, thereby increasing the display's aperture ratio by reducing the lateral spacing between OLED devices on the substrate 10. The DBR 12, the first electrodes 14A and 14B, and the first color vias 16A and 16B remain intact on the substrate 10.

[0188] Figure 10J The diagram shows a second color via 24 etched using reactive ion etching through a first optical filler layer 18, a second optical filler layer 20, and a DBR 12. The first electrodes 14A and 14B and the first color vias 16A and 16B remain intact on the substrate 10.

[0189] Figure 10K A second color electrode 22, deposited by sputtering on a second optical filler layer 20, is shown, wherein the width of the second color electrode 22 is approximately equal to the width of the second optical filler layer 20. A second color via 24 provides electrical connection between the second color electrode 22 and the substrate 10. The first optical filler layer 18, first color electrodes 14A, 14B, first color vias 16A, 16B, and DBR 12 remain intact on the substrate 10.

[0190] Figure 10L A top view of the embodiment after the deposition of the second color electrode 22 is shown. The patterning of the first color electrodes 14A, 14B and the second color electrode 22 allows for minimal spacing between OLED devices on the OLED array. The emitted color can be any color in the visible spectrum, including but not limited to red, yellow, blue, and green. A preferred combination for the dual-color array is yellow and blue emission.

[0191] Figure 10M A white OLED stack 26 is shown deposited on a substrate 10, on which a second color electrode 22, a second optical filler layer 20, a first optical filler layer 18, a second color via 24, first color electrodes 14A and 14B, first color vias 16A and 16B, and a DBR 12 have been deposited. Figure 10M The white OLED stack 26 shown includes a series of organic material layers, and each layer of the white OLED stack 26 can be deposited by thermal evaporation, spin casting or inkjet printing.

[0192] Figure 10N The final step in the manufacturing process is illustrated: the deposition of cathode 28, creating optical microcavities for each OLED device in the OLED array. Cathode 28 can be deposited via thermal evaporation and sputtering. In this embodiment, thermal evaporation is the preferred deposition method. Multiple first and second color microcavities, formed by a second color electrode 22, a second optical filler layer 20, a first optical filler layer 18, a second color via 24, first color electrodes 14A, 14B, first color vias 16A, 16B, and DBR 12, along with a white OLED stack 26, form OLED array devices on substrate 10.

[0193] Figure 11A-V illustrates the step-by-step process for manufacturing a tricolor OLED array according to this disclosure.

[0194] Figure 11A The first step in the manufacturing process is illustrated, where DBR 12 is deposited on substrate 10. In this embodiment, substrate 10 is a TFT substrate, which is the device forming the basic structure of this embodiment. It should be understood that... Figure 11A The DBR 12 shown comprises alternating high-refractive-index dielectric layers and low-refractive-index dielectric layers. Each layer of the DBR 12 can be deposited by sputtering, thermal evaporation, chemical vapor deposition, and atomic layer deposition. The preferred deposition method for this embodiment is sputtering.

[0195] Figure 11B The diagram illustrates first color vias 16A and 16B connected to substrate 10 via dry etching using DBR 12. Each via can be etched using reactive ion etching, anodic plasma etching, magnetically enhanced reactive ion etching, triode reactive ion etching, and transmission-coupled plasma etching. In this embodiment, reactive ion etching is the preferred dry etching method.

[0196] Figure 11C The diagram shows first color electrodes 14A and 14B deposited on the DBR 12. First color vias 16A and 16B provide electrical connections between the first color electrodes 14A and 14B and the substrate 10. The electrodes can be patterned by sputtering, thermal evaporation, and spin coating. In this embodiment, sputtering is the preferred deposition method.

[0197] Figure 11D -G illustrates a series of photolithography steps used to pattern the first optical filler layer. It is understood that photolithography is a widely used manufacturing technique that can be repeated... Figure 10D -G shows the steps for depositing all the optical filler layers disclosed herein.

[0198] Figure 11D A cross-sectional view of an embodiment after photoresist 74 deposition is shown. Deposition can be achieved by spin coating. Photoresist 74 is deposited on a structure including a substrate 10, on which a DBR 12 is deposited. First color electrodes 14A and 14B are stacked on the DBR 12 and connected to the substrate 10 through first color vias 16A and 16B, respectively. In this embodiment, the photomask uses a design with opaque portions in the pattern of the first color electrodes 14A and 14B.

[0199] exist Figure 11EIn this process, the structure with the photomask is exposed to UV light, which causes a chemical change in the photoresist 74 adjacent to the first color electrodes 14A and 14B, making it easier to etch. In this embodiment, the photoresist 74 is a positive photoresist. The layers of the first color electrodes 14A and 14B, the first color vias 16A and 16B, and the DBR 12 deposited on the substrate 10 remain intact.

[0200] Figure 11F The deposition of a first optical filler layer 18 over the entire OLED array is shown. The first optical filler layer 18 can be deposited by sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition. Sputtering is a preferred deposition method, as it allows the designer to precisely adjust the layer thickness during deposition. The substrate is then exposed to a stripping process that removes the photoresist 74 and the first optical filler layer 18 over the photoresist 74. The stripping agent can be a commercially available product that breaks down and removes the photoresist 74 without damaging the layers of the first optical filler layer 18, the first color electrodes 14A, 14B, the first color vias 16A, 16B, and the DBR 12 deposited on the substrate 10.

[0201] Figure 11G An embodiment is shown after removing the remaining photoresist and the first optical filler layer 18 deposited on the photoresist. The first optical filler layer 18, the first color electrodes 14A, 14B, the first color vias 16A, 16B, and the DBR 12 remain intact on the substrate 10.

[0202] Figure 11H A top view of the implementation after the photolithography steps are shown. A pattern of the first color electrodes 14A, 14B and the first optical filler layer 18 across the OLED array is shown, specifically illustrating how patterning eliminates the spacing between OLED devices in the OLED array.

[0203] Figure 11I The diagram shows a second optical filler layer 20 partially deposited on the first optical filler layer 18 and partially deposited on the first color electrode 14A to form an overlap region 80A. The second optical filler layer 20 can be deposited by sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition. A preferred deposition method is sputtering, which allows the designer to precisely adjust the layer thickness during deposition. The overlap region 80A provides tolerances to mitigate alignment errors in manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10. The layers of the first optical filler layer 18, first color electrodes 14A, 14B, first color vias 16A, 16B, and DBR 12 remain intact on the substrate 10.

[0204] Figure 11J A second color via 24 is shown, formed by dry etching through a first optical filler layer 18, a second optical filler layer 20, and a DBR 12 using reactive ion etching. The layers of the first color electrodes 14A, 14B, the first color vias 16A, 16B, and the DBR 12 remain intact on the substrate 10.

[0205] Figure 11K The second color electrode 22 is shown, for example, deposited on the second optical filler layer 20 by sputtering, wherein the width of the second color electrode 22 is approximately equal to the width of the second optical filler layer 20. A second color via 24 provides electrical connection between the second color electrode 22 and the substrate 10. The layers of the first optical filler layer 18, the first color electrodes 14A and 14B, the first color vias 16A and 16B, and the DBR 12 remain intact on the substrate 10.

[0206] Figure 11L A top view of the embodiment after the deposition of the second color electrode 22 is shown. The patterning of the first color electrodes 14A, 14B, the second color electrode 22, and the first optical filler layer 18 to which the third electrode will eventually be deposited allows for minimal spacing between OLED optical microcavity devices on the OLED array.

[0207] Figure 11M -P illustrates a series of photolithography steps used to pattern the third optical filler layer. It is understood that photolithography is a widely used and repeatable manufacturing technique. Figure 10D The steps shown in -G are used to deposit all the optical filler layers disclosed herein.

[0208] Figure 11M A cross-sectional view of an embodiment after photoresist 74 deposition is shown. Deposition can be achieved by spin coating. Photoresist 74 is deposited on a structure including a substrate 10, on which a DBR 12 is deposited. First color electrodes 14A and 14B are stacked on the DBR 12 and connected to the substrate 10 through first color vias 16A and 16B, respectively. A first optical filler layer 18 is deposited on the DBR 12, wherein a second optical filler layer 20 and a second color electrode 22 are stacked on the first optical filler layer 18, wherein the second color electrode 22 is connected to the substrate 10 through second color vias 24, respectively. Then, a photomask is applied with a design having opaque portions in the pattern of the first color electrodes 14A and 14B and the second color electrode 22 and partially covering the first color electrode 14B.

[0209] exist Figure 11NIn this process, the structure with the photomask is exposed to UV light, which causes a chemical change in the photoresist 74, making it dissolve in the etching of the transparent areas of the photomask. In this embodiment, the photoresist 74 is a positive photoresist. The layers of the first optical filler layer 18, the first color electrodes 14A and 14B, the first color vias 16A and 16B, the second optical filler layer 20, the second color electrode 22, the second color via 24, and the DBR 12 remain intact on the substrate 10.

[0210] Figure 11O A third optical filler layer 58 is shown deposited on a photoresist 74, which is deposited over the entire OLED array. The third optical filler layer 58 can be deposited, for example, by sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition. A preferred deposition method is sputtering, which allows the designer to precisely adjust the layer thickness during deposition. The substrate 10 is then exposed to a stripping process that removes the photoresist 74 and the third optical filler layer 58 deposited on it. The stripping agent can be a commercially available product that breaks down and removes the photoresist 74 without damaging the underlying layers. The layers of the first optical filler layer 18, first color electrodes 14A, 14B, first color vias 16A, 16B, second optical filler layer 20, second color electrode 22, second color via 24, and DBR 12 remain intact on the substrate 10.

[0211] Figure 11P The substrate 10 and its deposited layers are shown after the removal of the remaining photoresist and the third optical filler layer 58 deposited on the photoresist. The remaining third optical filler layer 58 may partially cover the first optical filler layer 18 and the first color electrode 14B to form an overlap region 80C. The layers of the first optical filler layer 18, the first color electrodes 14A and 14B, the first color vias 16A and 16B, the second optical filler layer 20, the second color electrode 22, the second color via 24, and the DBR 12 remain intact on the substrate 10.

[0212] Figure 11QA fourth optical filler layer 60 is shown deposited on the third optical filler layer 58, and the fourth optical filler layer 60 can overlap with the second color electrode 22 to form an overlap region 80D. The fourth optical filler layer 60 can be deposited by, for example, sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition. A preferred deposition method is sputtering, which allows the designer to precisely adjust the layer thickness during deposition. The overlap regions 80C, 80D can mitigate alignment errors in manufacturing, thereby increasing the aperture ratio of the display by reducing the lateral spacing between OLED devices on the substrate 10. The layers of the first optical filler layer 18, the first color electrodes 14A, 14B, the first color vias 16A, 16B, the second optical filler layer 20, the second color electrode 22, the second color via 24, and the DBR 12 remain intact on the substrate 10.

[0213] Figure 11R A third color via 64 is shown, etched using reactive ion etching through a first optical filler layer 18, a third optical filler layer 58, a fourth optical filler layer 60, and a DBR 12 dry etching process. The first optical filler layer 18, first color electrodes 14A and 14B, first color via 16A and 16B, second optical filler layer 20, second color electrode 22, and second color via 24 remain intact on the substrate 10.

[0214] Figure 11S A third color electrode 62 is shown, deposited, for example, on a fourth optical filler layer 60 by sputtering. The width of the third color electrode 62 is approximately equal to the width of the fourth optical filler layer 60. A third color via 64 provides electrical connection between the third color electrode 62 and the substrate 10. The first optical filler layer 18, first color electrodes 14A and 14B, first color vias 16A and 16B, second optical filler layer 20, second color electrode 22, second color via 24, third optical filler layer 58, and DBR 12 remain intact on the substrate 10.

[0215] Figure 11T A top view is shown after the deposition of the third color electrode 62. The patterning of the first color electrodes 14A, 14B, the second color electrode 22, and the third color electrode 62 allows for minimal spacing between OLED devices on the OLED array. The emitted color can be any color in the visible spectrum, including but not limited to red, yellow, blue, and green. A preferred combination of three colors in the array is red, green, and blue emission.

[0216] Figure 11U This shows a stack of white OLEDs 26 deposited over the entire OLED array. It should be understood that... Figure 11UThe white OLED stack 26 shown preferably comprises a series of layers made of organic materials. Each layer of the white OLED stack 26 can be deposited by thermal evaporation, spin casting, and inkjet printing. For this embodiment, thermal evaporation is the preferred method. The first optical filler layer 18, the first color electrodes 14A, 14B, the first color vias 16A, 16B, the second optical filler layer 20, the second color electrode 22, the second color via 24, the third optical filler layer 58, the third color electrode 62, the third color via 64, the fourth optical filler layer 60, and the DBR 12 remain intact on the substrate 10 beneath the white OLED stack 26.

[0217] Figure 11V The final step in the manufacturing process is illustrated, in which a cathode 28 is deposited on a white OLED stack 26 to create an optical microcavity for each OLED device in the OLED array. The cathode 28 can be deposited via thermal evaporation and sputtering. In this embodiment, thermal evaporation is the preferred deposition method. A first optical filler layer 18, first color electrodes 14A, 14B, first color vias 16A, 16B, a second optical filler layer 20, a second color electrode 22, a second color via 24, a third optical filler layer 58, a third color electrode 62, a third color via 64, a fourth optical filler layer 60, and a DBR 12 remain intact on the substrate 10.

[0218] All publications, patents, and patent applications mentioned in this specification demonstrate the skill of a person skilled in the art to which this invention pertains and are incorporated herein by reference. Any reference to prior art in this specification is not, and should not be construed as, an admission or in any way implying that such prior art constitutes part of common general knowledge.

[0219] As described herein, it will be apparent that the invention can be modified in various ways. These modifications should not be considered as departing from the scope of the invention, and all such modifications, which will be obvious to those skilled in the art, are intended to be included within the scope of the appended claims.

Claims

1. Organic light-emitting diode devices, including: substrate; A distributed Bragg reflector (DBR) is located on the substrate; A first color electrode is located on the distributed Bragg reflector and defines a first color microcavity, and the first color electrode is connected to the substrate through a first through-hole; A first optical filler layer is located on the distributed Bragg reflector, and the first optical filler layer is adjacent to the first color electrode on the distributed Bragg reflector; The first optical filler layer is transparent to visible light and electrically insulating; A second optical filler layer is located on top of the first optical filler layer and partially overlaps with the first color electrode in the overlapping region; the second optical filler layer is transparent to visible light and electrically insulating. A second color electrode is located on the second optical filler layer and defines a second color microcavity. The second color electrode is connected to the substrate through a second through-hole. A stack of white organic light-emitting diodes (OLEDs) is positioned above the first color electrode and the second color electrode; and The top electrode is located on top of the stack of white organic light-emitting diodes.

2. The device according to claim 1, wherein the second color electrode partially overlaps with the first color electrode.

3. The device according to claim 1 or 2, wherein the first color microcavity has a first color optical path length passing through the first color electrode between the distributed Bragg reflector and the top electrode, and the second color microcavity has a second color optical path length passing through the second color electrode between the distributed Bragg reflector and the top electrode.

4. The device according to claim 3, wherein the first color optical path length and the second color optical path length are adjusted to provide the desired first color pixel and second color pixel, respectively.

5. The device according to claim 1 or 2, wherein the first optical filler layer and the second optical filler layer comprise a transparent polymer.

6. The device according to claim 1 or 2, wherein the first optical filler layer and the second optical filler layer comprise a transparent inorganic dielectric.

7. The device according to claim 1 or 2, further comprising: A pixel-defining layer that insulates the first color electrode from the second color electrode.

8. The device of claim 7, wherein the pixel defining layer comprises one or more of an inorganic insulating dielectric and an organic material.

9. The device according to claim 1 or 2, wherein the substrate is a thin-film transistor (TFT) substrate.

10. The device according to claim 1 or 2, further comprising: A second distributed Bragg reflector above the top electrode.

11. The device according to claim 1 or 2, wherein the top electrode is a cathode and the first color and the second color electrodes are anodes.

12. The device according to claim 1 or 2, wherein the top electrode is an anode and the first color and the second color electrodes are cathodes.

13. The device according to claim 1 or 2, further comprising: Located above the second color electrode and below the stack of white organic light-emitting diodes: A third optical filler layer is located on the first optical filler layer and defines a third color microcavity; A fourth optical filler layer is located on top of the third optical filler layer, and the fourth optical filler layer partially overlaps with the second color electrode. as well as The third color electrode is located on the fourth light filler layer and partially overlaps with the second color electrode. The third color electrode is connected to the substrate through a third through-hole.

14. A method for fabricating a multicolor microcavity organic light-emitting diode (OLED) array, the method comprising: Deposit a distributed Bragg reflector (DBR) on a substrate. A first color electrode is deposited on the distributed Bragg reflector, the first color electrode defining a first color microcavity, and the first color electrode is connected to the substrate through a first via. A first optical filler layer is deposited on the distributed Bragg reflector, the first optical filler layer being adjacent to the first color electrode on the distributed Bragg reflector; A second optical filler layer is deposited on the first optical filler layer, wherein the second optical filler layer overlaps with the first color electrode portion in the overlapping region; A second color electrode is deposited on the second optical filler layer, the second color electrode defining a second color microcavity, and the second color electrode is connected to the substrate through a second via. A stack of white organic light-emitting diodes is deposited on the first color electrode and the second color electrode; as well as A top electrode is deposited on top of the white organic light-emitting diode stack.

15. The method of claim 14, wherein the white organic light-emitting diode stack is deposited over the entire organic light-emitting diode array.

16. The method of claim 14 or 15, wherein the white organic light-emitting diode stack is deposited using thermal evaporation, spin coating, or inkjet printing.

17. The method of claim 14 or 15, wherein thermal evaporation or sputtering is used to deposit the top electrode.

18. The method according to claim 14 or 15, further comprising: A pixel-defining layer is deposited to insulate the first color electrode from the second color electrode.

19. The method of claim 18, wherein the pixel defining layer is deposited using sputtering, spin coating, thermal evaporation, chemical vapor deposition, atomic layer deposition, or spin casting.

20. The method according to claim 14 or 15, further comprising: A second distributed Bragg reflector (DBR) is deposited on the top electrode.

21. The method of claim 14 or 15, wherein sputtering, thermal evaporation, or spin coating is used to deposit the first color electrode, the second color electrode, and the top electrode.

22. The method of claim 14 or 15, wherein sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition is used to deposit the first optical filler layer and the second optical filler layer.

23. The method of claim 14 or 15, wherein the distributed Bragg reflector is deposited using sputtering, thermal evaporation, chemical vapor deposition, or atomic layer deposition.

24. The method according to claim 14 or 15, further comprising: Before depositing the white organic light-emitting diode stack: A third optical filler layer, selected for the third color, is deposited on top of the first optical filler layer, the third optical filler layer overlapping the first color electrode; A fourth optical filler layer, selected for the third color, is deposited on top of the third optical filler layer, which overlaps with the second color electrode. as well as A series of third color electrodes are deposited on the fourth optical filler layer.

Images