CN118302012A - Organic vapor jet printing system - Google Patents

Abstract

The present application relates to an organic vapor jet printing system. Embodiments of the disclosed subject matter provide a laser source configured to output a laser beam; a beam delivery cavity receiving the output laser beam on a first side of the device and outputting the laser beam on a second side of the device, wherein the first side is opposite the second side; and a plume removal device having an exhaust hole on the second side of the apparatus facing the heat affected zone, HAZ. The bottom surface of the plume removal device may face the substrate, wherein organic matter is disposed on the substrate, and the HAZ may be aligned with a surface of the substrate having the organic matter to be ablated by the laser beam.

Description

Organic vapor jet printing system

Cross reference to related applications

The present application claims priority from U.S. patent application Ser. No. 63/437,174 filed on 1/5 of 2023, the entire contents of which are incorporated herein by reference.

Technical Field

The present invention relates to an apparatus to remove deposited organic layers to achieve cleanliness of the encapsulation process without causing redeposition of ablated material on the substrate, and techniques for using the apparatus.

Background

Optoelectronic devices utilizing organic materials are becoming increasingly popular for a number of reasons. Many of the materials used to fabricate the devices are relatively inexpensive, so organic photovoltaic devices have the potential for cost advantages over inorganic devices. In addition, the inherent properties of organic materials (e.g., their flexibility) may make them more suitable for specific applications, such as fabrication on flexible substrates. Examples of organic optoelectronic devices include organic light emitting diodes/devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials can have performance advantages over conventional materials. For example, the wavelength at which the organic emissive layer emits light can generally be readily tuned with appropriate dopants.

OLEDs utilize organic thin films that emit light when a voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in applications such as flat panel displays, lighting and backlighting. Several OLED materials and configurations are described in U.S. patent nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.

One application of phosphorescent emissive molecules is in full color displays. Industry standards for such displays require pixels adapted to emit a particular color (referred to as a "saturated" color). In particular, these standards require saturated red, green and blue pixels. Or the OLED may be designed to emit white light. In conventional liquid crystal displays, the emission from a white backlight is filtered using an absorbing filter to produce red, green and blue emissions. The same technique can also be used for OLEDs. The white OLED may be a single EML device or a stacked structure. The color may be measured using CIE coordinates well known in the art.

As used herein, the term "organic" includes polymeric materials and small molecule organic materials that can be used to fabricate organic optoelectronic devices. "Small molecule" refers to any organic material that is not a polymer, and may be substantial in nature. In some cases, the small molecule may include repeat units. For example, the use of long chain alkyl groups as substituents does not remove the molecule from the "small molecule" class. Small molecules may also be incorporated into the polymer, for example as side groups on the polymer backbone or as part of the backbone. Small molecules can also serve as the core of a dendrimer, which consists of a series of chemical shells built on the core. The core moiety of the dendrimer may be a fluorescent or phosphorescent small molecule emitter. Dendrimers may be "small molecules" and all dendrimers currently used in the OLED field are considered small molecules.

As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. Where a first layer is described as being "disposed" over "a second layer, the first layer is disposed farther from the substrate. Unless a first layer is "in contact with" a second layer, other layers may be present between the first and second layers. For example, a cathode may be described as "disposed over" an anode even though various organic layers are present between the cathode and the anode.

As used herein, "solution processable" means capable of being dissolved, dispersed, or transported in and/or deposited from a liquid medium in the form of a solution or suspension.

A ligand may be referred to as "photosensitive" when it is believed that the ligand contributes directly to the photosensitive properties of the emissive material. When the ligand is considered not to contribute to the photosensitive properties of the emissive material, the ligand may be referred to as "ancillary", but the ancillary ligand may alter the properties of the photosensitive ligand.

As used herein, and as will be generally understood by those of skill in the art, if the first energy level is closer to the vacuum energy level, then the first "highest occupied molecular orbital" (Highest Occupied Molecular Orbital, HOMO) or "lowest unoccupied molecular orbital" (Lowest Unoccupied Molecular Orbital, LUMO) energy level is "greater than" or "higher than" the second HOMO or LUMO energy level. Since Ionization Potential (IP) is measured as a negative energy relative to the vacuum level, a higher HOMO level corresponds to an IP with a smaller absolute value (a less negative (LESS NEGATIVE) IP). Similarly, a higher LUMO energy level corresponds to an Electron Affinity (EA) with a smaller absolute value (less negative EA). On a conventional energy level diagram with vacuum energy level on top, the LUMO energy level of a material is higher than the HOMO energy level of the same material. The "higher" HOMO or LUMO energy level appears closer to the top of this figure than the "lower" HOMO or LUMO energy level.

As used herein, and as will be generally understood by those of skill in the art, a first work function is "greater than" or "higher than" a second work function if the first work function has a higher absolute value. Since work function is typically measured as a negative number relative to the vacuum level, this means that the "higher" work function is more negative (more negative). On a conventional energy level diagram with the vacuum energy level on top, a "higher" work function is illustrated as being farther from the vacuum energy level in a downward direction. Thus, the definition of HOMO and LUMO energy levels follows a different rule than work function.

Layers, materials, regions and colors of light emitted by devices may be described herein with reference to them. In general, as used herein, an emissive region described as producing a particular color of light may include one or more emissive layers disposed on top of each other in a stacked fashion.

As used herein, a "red" layer, material, region or device refers to a layer, material, region or device that emits light in the range of about 580-700nm or whose emission spectrum has the highest peak in that region. Similarly, a "green" layer, material, region or device refers to a layer, material, region or device that emits or has an emission spectrum with a peak wavelength in the range of about 500-600 nm; "blue" layer, material or device refers to a layer, material or device that emits or has an emission spectrum with a peak wavelength in the range of about 400-500 nm; and a "yellow" layer, material, region or device refers to a layer, material, region or device having an emission spectrum with a peak wavelength in the range of about 540-600 nm. In some arrangements, individual regions, layers, materials, regions, or devices may provide individual "deep blue" and "light blue" light. As used herein, in an arrangement that provides separate "light blue" and "dark blue" components, a "dark blue" component refers to a component having a peak emission wavelength that is at least about 4nm less than the peak emission wavelength of the "light blue" component. Typically, the peak emission wavelength of the "light blue" component is in the range of about 465nm to 500nm, and the peak emission wavelength of the "deep blue" component is in the range of about 400nm to 470nm, although these ranges may vary for some configurations. Similarly, a color changing layer refers to a layer that converts or modifies light of another color into light having a wavelength specified for that color. For example, a "red" color filter refers to a color filter that forms light having a wavelength in the range of about 580-700 nm. In general, there are two types of color changing layers: a color filter to modify the spectrum by removing unwanted wavelengths of light, and a color changing layer to convert higher energy photons to lower energy. "color" component refers to a component that, when activated or in use, generates or otherwise emits light having a particular color as previously described. For example, "a first emission region of a first color" and "a second emission region of a second color different from the first color" describe two emission regions that emit two different colors as previously described when activated within a device.

As used herein, emissive materials, layers, and regions may be distinguished from one another and from other structures based on light originally generated by the materials, layers, or regions, rather than light ultimately emitted by the same or different structures. Initial light generation is typically the result of a change in energy level that results in photon emission. For example, an organic emissive material may initially produce blue light, which may be converted to red or green light by a color filter, quantum dot, or other structure, such that the complete emissive stack or subpixel emits red or green light. In this case, the initial emissive material or layer may be referred to as the "blue" component, even though the subpixels are of the "red" or "green" components.

In some cases, it may be preferable to describe the color of components, such as the color of the emission area, sub-pixels, color changing layers, etc., according to 1931CIE coordinates. For example, the yellow emissive material may have multiple peak emission wavelengths, one in or near the edge of the "green" region, and one within or near the edge of the "red" region, as previously described. Thus, as used herein, each color item also corresponds to a shape in the 1931CIE coordinate color space. The shape in the 1931CIE color space is constructed by following a trajectory between two color points and any other internal points. For example, the internal shape parameters of red, green, blue, and yellow may be defined as follows:

Further details regarding OLEDs and the definitions described above can be found in U.S. patent No.7,279,704, which is incorporated herein by reference in its entirety.

Disclosure of Invention

According to one embodiment, an organic light emitting diode/device (OLED) is also provided. An OLED may include an anode, a cathode, and an organic layer disposed between the anode and the cathode. According to one embodiment, the organic light emitting device is incorporated into one or more devices selected from consumer products, electronic component modules, and/or lighting panels.

According to one embodiment, an apparatus may include: a laser source configured to output a laser beam; a beam delivery cavity to receive an output laser beam on a first side of the device and output the laser beam on a second side of the device, wherein the first side is opposite the second side; and a plume removal device having an exhaust vent on the second side of the apparatus facing a Heat Affected Zone (HAZ).

According to one embodiment, an apparatus may include: a laser source configured to output a laser beam; a beam delivery chamber to receive the output laser beam and output the laser beam to a substrate; and a plume removal device having an exhaust vent adjacent to a Heat Affected Zone (HAZ) on the substrate and disposed at an initial predetermined distance from the substrate, wherein a bottom surface of the plume removal device is parallel to or facing the substrate, wherein organic matter is disposed on the substrate and the HAZ is aligned with a surface of the substrate having the organic matter to be ablated by the laser beam.

The beam delivery cavity may be filled with an optically transparent material. The optically transparent material may comprise a sapphire material.

The size of the feature of the organic material to be removed by ablation with a laser beam may be greater than or equal to 1mm.

The apparatus may be disposed in a vacuum chamber having an inert gas at a pressure level controlled by a controller. The plume removal device may include an internal network of micro-channels configured to utilize the inert gas flow of the chamber to extract organic vapors formed by laser beam ablation. The apparatus may include an exhaust source in fluid communication with an exhaust channel configured to remove inert gas and ablated material from the chamber. The exhaust source may have a lower pressure than the chamber environment. The plume removal device may be configured to have a radial inflow of inert gas from the chamber towards the outlet aperture of the plume removal device. The plume removal device may be disposed at a predetermined distance from the substrate and configured to cause inert gas of the chamber to flow along a plane of the substrate.

The plume removal device may be formed of at least one of steel and/or aluminum.

The apparatus may include at least one heater configured to heat the plume removal device.

The apparatus may include a cold plate disposed above a platen configured to hold a substrate, wherein the cold plate includes a window configured to allow a laser beam to pass through. The cold plate and plume removal device may be mounted on the same frame that is disposed above and separate from the platform holding the substrate. The window may be a slit configured to allow the laser beam to pass through, and configured to allow the organic matter ablated by the laser beam to pass toward the plume removal device.

The apparatus may include a thermal shield disposed above a platform configured to hold a substrate, wherein the thermal shield includes a window configured to allow a laser beam to pass through. The window of the thermal shield may be configured to allow organic matter ablated by the laser beam to pass toward the plume removal device. The thermal shield and plume removal device may be mounted on the same frame that is disposed above and separate from the platform holding the substrate. The window may include a cutout configured to allow the laser beam to pass therethrough, and may be configured to allow the organic matter ablated by the laser beam to pass toward the plume removal device.

The laser beam output by the laser may be configured to produce a pattern in the HAZ, and at least one pulse of the laser beam may have a diameter of 50-100 microns.

The flying height between the bottom surface of the plume removing device and the organic substance may be 50 μm to 1mm.

The apparatus may include a sensor configured to detect a change in a surface height of an organic substance disposed on the substrate, and a controller to control a flying height between a bottom surface of the plume removal device and the organic substance based on the detected change.

The substrate may be disposed on a stage, and the stage may be spaced apart from the laser source.

The substrate is disposed on a stage configured to linearly translate at a predetermined rate. The laser, the beam delivery cavity, and the plume removal device may be configured to be movable in a direction opposite to the linear translation of the platform.

The substrate may be mounted on a stage and the laser, beam delivery chamber and plume removal device may be configured to be movable relative to the stage which is configured to be stationary.

The apparatus may include a plurality of channels connected to at least one vent slot of the plume removal device.

The apparatus may include a plurality of channels connected to a plurality of vent slots of the plume removal device, wherein the plurality of vent slots are radially connected.

The substrate may have a first side and a second side, and the organic substance is disposed on the first side. The laser source may be spaced apart from the substrate to be closer to the second side of the substrate, and the plume removal device and the beam delivery chamber may be spaced apart from the substrate to be closer to organic matter disposed on the first side of the substrate.

The substrate may have a first side and a second side, and the organic substance may be disposed on the first side. The plume removal device, the beam delivery chamber, and the laser source may be spaced apart from the substrate to be closer to organic matter disposed on the first side of the substrate.

Drawings

Fig. 1 shows an organic light emitting device.

Fig. 2 illustrates an inverted organic light emitting device without a separate electron transport layer.

Fig. 3 illustrates a plume removal device according to an embodiment of the disclosed subject matter.

Fig. 4 illustrates example dimensions of a plume removal device used in Computational Fluid Dynamics (CFD) studies according to an embodiment of the disclosed subject matter.

FIG. 5 illustrates example boundary conditions in a CFD model according to an embodiment of the disclosed subject matter.

Fig. 6A shows time variation of molar flow rates of organic vapor at the source and outlet according to an embodiment of the disclosed subject matter.

Fig. 6B illustrates efficiency values as the flow rate and altitude of the organic vapor changes in accordance with an embodiment of the disclosed subject matter.

Fig. 7 illustrates example images of plume transmission at different times during an ablation process according to an embodiment of the disclosed subject matter.

Fig. 8 illustrates a linearly moving substrate that may be represented by a steady state CFD model with a constant organic vapor source, according to an embodiment of the disclosed subject matter.

Fig. 9 illustrates a cross-sectional view of a fluid field in accordance with an embodiment of the disclosed subject matter, wherein gray scale displays vapor concentration and arrows indicate the direction of chamber gas and vapor flux.

FIG. 10 illustrates streamlines of vapor flux removed from a source at various fly-height values according to an embodiment of the disclosed subject matter.

FIG. 11 illustrates streamlines of vapor flux removed from a source under various exhaust flow conditions according to an embodiment of the disclosed subject matter.

Fig. 12 illustrates an example design of a removal device with an outer manifold ring for flow uniformity in accordance with an embodiment of the disclosed subject matter.

FIG. 13 illustrates an example design with single and dual sets of vent holes according to an embodiment of the disclosed subject matter.

Fig. 14 illustrates an example plume removal device with radially outward delivery flow according to an embodiment of the disclosed subject matter.

Fig. 15-16 illustrate different views of an example plume removal device in a cross-flow configuration according to embodiments of the disclosed subject matter.

Fig. 17-18 illustrate example plume removal devices and additional components similar to the plume removal device shown in fig. 3, according to embodiments of the disclosed subject matter.

Fig. 19 illustrates a laser film removal process to separate lines printed by OVJP into discrete pixels, according to an embodiment of the disclosed subject matter.

Fig. 20 illustrates a plume removal system according to an embodiment of the disclosed subject matter.

Detailed Description

In general, an OLED includes at least one organic layer disposed between and electrically connected to an anode and a cathode. When a current is applied, the anode injects holes and the cathode injects electrons into the organic layer. The injected holes and electrons each migrate toward the oppositely charged electrode. When an electron and a hole are localized on the same molecule, an "exciton" is formed, which is a localized electron-hole pair having an excited energy state. Light is emitted when the exciton relaxes through a light emission mechanism. In some cases, excitons may be localized on an excimer (excimer) or an exciplex. Non-radiative mechanisms (such as thermal relaxation) may also occur, but are generally considered undesirable.

Initial OLEDs used emissive molecules that emitted light ("fluorescence") from a singlet state, as disclosed, for example, in U.S. patent No. 4,769,292, which is incorporated by reference in its entirety. Fluorescence emission typically occurs in time frames less than 10 nanoseconds.

Recently, OLEDs have been demonstrated that have emissive materials that emit light from a triplet state ("phosphorescence"). Baldo et al, "efficient phosphorescent emission from organic electroluminescent devices (HIGHLY EFFICIENT Phosphorescent Emission from Organic Electroluminescent Devices)", nature, volume 395, 151-154,1998 ("Baldo-I"); and Barduo et al, "Very high efficiency green organic light emitting device based on electrophosphorescence (Very high-EFFICIENCY GREEN organic light-EMITTING DEVICES based on electrophosphorescence)", applied physical fast report (appl. Phys. Lett.), vol.75, stages 3,4-6 (1999) ("Barduo-II"), incorporated by reference in its entirety. Phosphorescence is described in more detail in U.S. Pat. No.7,279,704, columns 5-6, which is incorporated by reference.

Fig. 1 shows an organic light emitting device 100. The figures are not necessarily drawn to scale. The device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, an emissive layer 135, a hole blocking layer 140, an electron transport layer 145, an electron injection layer 150, a protective layer 155, a cathode 160, and a blocking layer 170. Cathode 160 is a composite cathode having a first conductive layer 162 and a second conductive layer 164. The device 100 may be fabricated by depositing the layers in sequence. The nature and function of these various layers and example materials are described in more detail in U.S. Pat. No. 7,279,704 at columns 6-10, which is incorporated by reference.

Further examples of each of these layers are available. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. patent No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F ₄ -TCNQ at a molar ratio of 50:1, as disclosed in U.S. patent application publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of emissive and host materials are disclosed in U.S. Pat. No. 6,303,238 to Thompson et al, which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li in a molar ratio of 1:1, as disclosed in U.S. patent application publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of cathodes are disclosed in U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, that include composite cathodes having a thin layer of metal (e.g., mg: ag) containing an overlying transparent, electrically conductive, sputter-deposited ITO layer. The theory and application of the barrier layer is described in more detail in U.S. Pat. No. 6,097,147 and U.S. patent application publication No. 2003/0230980, which are incorporated by reference in their entirety. Examples of implanted layers are provided in U.S. patent application publication No. 2004/0174116, which is incorporated by reference in its entirety. The barrier layer 170 may be a single or multiple layer barrier layer and may cover or surround other layers of the device. The barrier layer 170 may also surround the substrate 110 and/or it may be disposed between the substrate and other layers of the device. The barrier layer may also be referred to as an encapsulant, encapsulation layer, protective layer, or permeation barrier, and generally provides protection against moisture, ambient air, and other similar materials from penetrating other layers of the device. Examples of barrier materials and structures are provided in U.S. patent nos. 6,537,688, 6,597,111, 6,664,137, 6,835,950, 6,888,305, 6,888,307, 6,897,474, 7,187,119, and 7,683,534, each of which is incorporated by reference in its entirety.

Fig. 2 shows an inverted OLED 200. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole transport layer 225, and an anode 230. The device 200 may be fabricated by depositing the layers in sequence. Because the most common OLED configuration has a cathode disposed above an anode, and the device 200 has a cathode 215 disposed below an anode 230, the device 200 may be referred to as an "inverted" OLED. Materials similar to those described with respect to device 100 may be used in the corresponding layers of device 200. Fig. 2 provides one example of how some layers may be omitted from the structure of the apparatus 100.

The simple layered structure illustrated in fig. 1 and 2 is provided by way of non-limiting example, and it should be understood that embodiments of the present invention may be used in conjunction with a variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures may be used. Functional OLEDs may be obtained by combining the various layers described in different ways, or the layers may be omitted entirely based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many of the examples provided herein describe the various layers as comprising a single material, it should be understood that combinations of materials may be used, such as mixtures of host and dopant, or more generally, mixtures. Further, the layers may have various sublayers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole transport layer 225 transports holes and injects holes into emissive layer 220, and may be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED may be described as having an "organic layer" disposed between a cathode and an anode. This organic layer may comprise a single layer, or may further comprise multiple layers of different organic materials as described, for example, with respect to fig. 1 and 2.

Structures and materials not specifically described, such as OLEDs (PLEDs) comprising polymeric materials, such as disclosed in frank (Friend) et al, U.S. patent No. 5,247,190, which is incorporated by reference in its entirety, may also be used. By way of another example, an OLED with a single organic layer may be used. The OLEDs can be stacked, for example, as described in U.S. patent No. 5,707,745 to Forrest et al, which is incorporated by reference in its entirety. The OLED structure may deviate from the simple layered structure illustrated in fig. 1 and 2. For example, the substrate may include an angled reflective surface to improve out-coupling, such as a mesa structure as described in U.S. Pat. No. 6,091,195 to Furster et al, and/or a pit structure as described in U.S. Pat. No. 5,834,893 to Boolean et al, which are incorporated by reference in their entirety.

In some embodiments disclosed herein, emissive layers or materials, such as emissive layer 135 and emissive layer 220 shown in fig. 1-2, respectively, may comprise quantum dots. Unless specifically indicated to the contrary or otherwise indicated as appropriate to the understanding of those skilled in the art, an "emissive layer" or "emissive material" as disclosed herein may include organic emissive materials and/or emissive materials comprising quantum dots or equivalent structures. In general, the emissive layer comprises an emissive material within a host matrix. Such an emissive layer may comprise only quantum dot materials that convert light emitted by the individual emissive material or other emitter, or it may also comprise individual emissive materials or other emitters, or it may itself emit light directly by application of an electrical current. Similarly, a color changing layer, color filter, up-conversion or down-conversion layer or structure may include a material containing quantum dots, but such layers may not be considered "emissive layers" as disclosed herein. In general, an "emissive layer" or material is a material that emits an initial light based on injected charge, where the initial light may be altered by another layer, such as a color filter or other color altering layer, that does not itself emit the initial light within the device, but may re-emit altered light having a different spectral content based on absorption and down-conversion of the initial light emitted by the emissive layer to a lower energy light emission. In some embodiments disclosed herein, the color changing layer, color filter, up-conversion and/or down-conversion layer may be disposed external to the OLED device, such as above or below an electrode of the OLED device.

Any of the layers of the various embodiments may be deposited by any suitable method unless otherwise specified. Preferred methods for the organic layer include thermal evaporation, ink jet (as described in U.S. Pat. Nos. 6,013,982 and 6,087,196, incorporated by reference in their entirety), organic vapor deposition (OVPD) (as described in U.S. Pat. No. 6,337,102, incorporated by reference in its entirety), and deposition by Organic Vapor Jet Printing (OVJP) (as described in U.S. Pat. No. 7,431,968, incorporated by reference in its entirety). Other suitable deposition methods include spin-coating and other solution-based processes. The solution-based process is preferably carried out under nitrogen or an inert atmosphere. For other layers, the preferred method includes thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding (as described in U.S. patent nos. 6,294,398 and 6,468,819, incorporated by reference in their entirety), and patterning associated with some of the deposition methods, such as inkjet and OVJD. Other methods may also be used. The material to be deposited may be modified to suit the particular deposition method. For example, substituents such as alkyl and aryl groups that are branched or unbranched and preferably contain at least 3 carbons can be used in small molecules to enhance their ability to withstand solution processing. Substituents having 20 carbons or more may be used, and 3 to 20 carbons are a preferred range. A material with an asymmetric structure may have better solution processibility than a material with a symmetric structure because an asymmetric material may have a lower tendency to recrystallize. Dendrimer substituents may be used to enhance the ability of small molecules to undergo solution processing.

Devices fabricated according to embodiments of the present invention may further optionally include a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from harmful substances exposed to the environment including moisture, vapors and/or gases, etc. The barrier layer may be deposited on the substrate, electrode, under or beside the substrate, electrode, or on any other portion of the device, including the edge. The barrier layer may comprise a single layer or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques and may include a composition having a single phase and a composition having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate inorganic compounds or organic compounds or both. Preferred barrier layers comprise a mixture of polymeric and non-polymeric materials, as described in U.S. patent No. 7,968,146, PCT patent application No. PCT/US2007/023098, and PCT/US2009/042829, which are incorporated herein by reference in their entirety. To be considered as a "mixture", the aforementioned polymeric and non-polymeric materials that make up the barrier layer should be deposited under the same reaction conditions and/or simultaneously. The weight ratio of polymeric material to non-polymeric material may be in the range of 95:5 to 5:95. The polymeric material and the non-polymeric material may be produced from the same precursor material. In one example, the mixture of polymeric and non-polymeric materials consists essentially of polymeric silicon and inorganic silicon.

In some embodiments, at least one of the anode, cathode, or new layer disposed over the organic emissive layer is used as the enhancement layer. The enhancement layer includes a plasmonic material exhibiting surface plasmon resonance, the plasmonic material non-radiatively coupled to the emitter material and transferring excited state energy from the emitter material to a non-radiative mode of surface plasmon polaritons. The enhancement layer is provided at a threshold distance from the organic emissive layer that is no more than a total non-radiative decay rate constant and a total radiative decay rate constant due to the presence of the enhancement layer, and the threshold distance is a distance where the total non-radiative decay rate constant is equal to the total radiative decay rate constant. In some embodiments, the OLED further comprises an outcoupling layer. In some embodiments, the outcoupling layer is disposed over the enhancement layer on an opposite side of the organic emissive layer. In some embodiments, the outcoupling layer is disposed on the opposite side of the emissive layer from the enhancement layer, but still allows energy to be outcoupled from the surface plasmon mode of the enhancement layer. The outcoupling layer scatters energy from the surface plasmon polaritons. In some embodiments, this energy is scattered into free space in the form of photons. In other embodiments, energy is scattered from surface plasmon modes of the device into other modes, such as, but not limited to, an organic waveguide mode, a substrate mode, or another waveguide mode. If the energy is scattered into the non-free space mode of the OLED, other outcoupling schemes may be incorporated to extract the energy into free space. In some embodiments, one or more intervening layers may be disposed between the enhancement layer and the outcoupling layer. Examples of intervening layers may be dielectric materials, including organic, inorganic, perovskite, oxide, and may include stacks and/or mixtures of these materials.

The enhancement layer modifies the effective properties of the medium in which the emitter material resides, causing any or all of the following: reduced emissivity, modification of emission line shape, variation of emission intensity and angle, variation of stability of the emitter material, variation of efficiency of the OLED, and reduction of efficiency decay of the OLED device. Placing the enhancement layer on the cathode side, the anode side, or both sides creates an OLED device that takes advantage of any of the effects described above. In addition to the specific functional layers mentioned herein and illustrated in the various OLED examples shown in the figures, an OLED according to the present invention may also include any of the other functional layers that are typically found in an OLED.

The enhancement layer may be composed of a plasmonic material, an optically active metamaterial or a hyperbolic metamaterial. As used herein, plasmonic materials are materials in which the real part of the dielectric constant crosses zero in the visible or ultraviolet region of the electromagnetic spectrum. In some embodiments, the plasmonic material comprises at least one metal. In such embodiments, the metal may include at least one of: ag. Al, au, ir, pt, ni, cu, W, ta, fe, cr, mg, ga, rh, ti, ru, pd, in, bi, ca, alloys or mixtures of these materials, and stacks of these materials. In general, metamaterials are media composed of different materials, where the media as a whole acts differently than the sum of its material portions. Specifically, we define an optically active metamaterial as a material having both negative permittivity and negative permeability. On the other hand, hyperbolic metamaterials are anisotropic media in which the permittivity or permeability has different signs for different spatial directions. Optically active metamaterials and hyperbolic metamaterials are strictly distinguished from many other photonic structures, such as distributed Bragg reflectors (Distributed Bragg Reflector, "DBR"), because the medium should exhibit uniformity in the direction of propagation over the length scale of the wavelength of light. Using terms that will be understood by those skilled in the art: the dielectric constant of a metamaterial in the direction of propagation can be approximately described by an effective medium. Plasmonic materials and metamaterials provide a means of controlling light propagation that can enhance OLED performance in a variety of ways.

In some embodiments, the enhancement layer is provided as a planar layer. In other embodiments, the enhancement layer has wavelength-sized features that are periodically, quasi-periodically, or randomly arranged, or sub-wavelength-sized features that are periodically, quasi-periodically, or randomly arranged. In some embodiments, the wavelength-sized features and the sub-wavelength-sized features have sharp edges.

In some embodiments, the outcoupling layer has a periodically, quasi-periodically, or randomly arranged wavelength-sized feature, or has a periodically, quasi-periodically, or randomly arranged sub-wavelength-sized feature. In some embodiments, the outcoupling layer may be composed of a plurality of nanoparticles, and in other embodiments, the outcoupling layer is composed of a plurality of nanoparticles disposed on a material. In these embodiments, the outcoupling may be tuned by at least one of: changing the size of the plurality of nanoparticles, changing the shape of the plurality of nanoparticles, changing the material of the plurality of nanoparticles, adjusting the thickness of the material, changing the refractive index of the material or an additional layer disposed on the plurality of nanoparticles, changing the thickness of the reinforcing layer, and/or changing the material of the reinforcing layer. The plurality of nanoparticles of the device may be formed from at least one of: a metal, a dielectric material, a semiconductor material, a metal alloy, a mixture of dielectric materials, a stack or layering of one or more materials, and/or a core of one type of material, and the core is coated with a shell of a different type of material. In some embodiments, the outcoupling layer is composed of at least metal nanoparticles, wherein the metal is selected from the group consisting of: ag. Al, au, ir, pt, ni, cu, W, ta, fe, cr, mg, ga, rh, ti, ru, pd, in, bi, ca, alloys or mixtures of these materials, and stacks of these materials. The plurality of nanoparticles may have additional layers disposed over them. In some embodiments, the polarization of the emission may be tuned using an outcoupling layer. Changing the dimensions and periodicity of the outcoupling layer may select a class of polarizations that preferentially outcouple to air. In some embodiments, the outcoupling layer also serves as an electrode of the device.

It is believed that the Internal Quantum Efficiency (IQE) of fluorescent OLEDs can be limited by spin statistics that delay fluorescence by more than 25%. As used herein, there are two types of delayed fluorescence, namely P-type delayed fluorescence and E-type delayed fluorescence. The P-type delayed fluorescence is generated by triplet-triplet annihilation (TTA).

On the other hand, the E-type delayed fluorescence does not depend on the collision of two triplet states, but on the number of thermal population between triplet and singlet excited states. Compounds capable of generating E-type delayed fluorescence are needed to have very small singlet-triplet gaps. The thermal energy may activate a transition from the triplet state back to the singlet state. This type of delayed fluorescence is also known as Thermally Activated Delayed Fluorescence (TADF). One significant feature of TADF is that the delay component increases with increasing temperature due to increasing thermal energy. The fraction of backfill singlet excited states may reach 75% if the rate of intersystem crossing is sufficiently fast to minimize non-radiative decay from the triplet states. The total singlet fraction may be 100%, well beyond the spin statistical limit of the electrically generated excitons.

Type E delayed fluorescence features can be found in excitation complex systems or in single compounds. Without being bound by theory, it is believed that the E-delayed fluorescence requires that the luminescent material have a small singlet-triplet energy gap (Δes-T). Organic, metal-free donor-acceptor luminescent materials may be able to achieve this. The emission of these materials is generally characterized by a donor-acceptor Charge Transfer (CT) type emission. The spatial separation of HOMO from LUMO in these donor-acceptor type compounds generally results in a small Δes-T. These states may relate to CT states. Typically, donor-acceptor luminescent materials are constructed by linking an electron donor moiety (e.g., an amino or carbazole derivative) to an electron acceptor moiety (e.g., containing an N six-membered aromatic ring).

Devices manufactured in accordance with embodiments of the present invention may be incorporated into a wide variety of electronic component modules (or units), which may be incorporated into a wide variety of electronic products or intermediate components. Examples of such electronic products or intermediate components include display screens, lighting devices (e.g., discrete light source devices or lighting panels), etc., that may be utilized by end user product manufacturers. The electronics assembly module may optionally include drive electronics and/or a power source. Devices manufactured in accordance with embodiments of the present invention may be incorporated into a wide variety of consumer products having one or more electronic component modules (or units) incorporated therein. Disclosed is a consumer product comprising an OLED comprising a compound of the present disclosure in an organic layer in the OLED. The consumer product should include any kind of product that contains one or more light sources and/or one or more of some type of visual display. Some examples of such consumer products include flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for interior or exterior illumination and/or signaling, heads-up displays, fully or partially transparent displays, flexible displays, rollable displays, foldable displays, stretchable displays, laser printers, telephones, cellular telephones, tablet computers, tablet phones, personal Digital Assistants (PDAs), wearable devices, laptop computers, digital cameras, video cameras, viewfinders, micro-displays with a diagonal of less than 2 inches, 3D displays, virtual or augmented reality displays, vehicles, video walls including a plurality of tiled displays, theatre or gym screens, and signs. Various control mechanisms may be used to control devices made in accordance with the present invention, including passive matrices and active matrices. Many of the devices are intended to be used in a temperature range that is comfortable for humans, such as 18 ℃ to 30 ℃, and more preferably at room temperature (20-25 ℃), but can be used outside this temperature range (e.g., -40 ℃ to 80 ℃).

The materials and structures described herein may be applied in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors may employ the materials and structures. More generally, organic devices such as organic transistors may employ the materials and structures.

In some embodiments, the OLED has one or more features selected from the group consisting of: flexible, crimpable, collapsible, stretchable and bendable. In some embodiments, the OLED is transparent or translucent. In some embodiments, the OLED further comprises a layer comprising carbon nanotubes.

In some embodiments, the OLED further comprises a layer comprising a delayed fluorescent emitter. In some embodiments, the OLED includes an RGB pixel arrangement or a white plus color filter pixel arrangement. In some embodiments, the OLED is a mobile device, a handheld device, or a wearable device. In some embodiments, the OLED is a display panel having a diagonal of less than 10 inches or an area of less than 50 square inches. In some embodiments, the OLED is a display panel having a diagonal of at least 10 inches or an area of at least 50 square inches. In some embodiments, the OLED is an illumination panel.

In some embodiments of the emission region, the emission region further comprises a body.

In some embodiments, the compound may be an emissive dopant. In some embodiments, the compound may produce emission via phosphorescence, fluorescence, thermally activated delayed fluorescence (i.e., TADF, also known as delayed fluorescence of type E), triplet-triplet annihilation, or a combination of these processes.

The OLEDs disclosed herein can be incorporated into one or more of consumer products, electronics assembly modules, and lighting panels. The organic layer may be an emissive layer, and the compound may be an emissive dopant in some embodiments, and the compound may be a non-emissive dopant in other embodiments.

The organic layer may further include a host. In some embodiments, two or more bodies are preferred. In some embodiments, the host used may be a) bipolar, b) electron transport, c) hole transport, or d) a wide bandgap material that plays a small role in charge transport. In some embodiments, the host may include a metal complex. The host may be an inorganic compound.

In combination with other materials

Materials described herein as suitable for use in particular layers in an organic light emitting device may be used in combination with a variety of other materials present in the device. For example, the emissive dopants disclosed herein can be used in combination with a wide variety of hosts, transport layers, barrier layers, implant layers, electrodes, and other layers that may be present. The materials described or mentioned below are non-limiting examples of materials that may be used in combination with the compounds disclosed herein, and one of ordinary skill in the art may readily review the literature to identify other materials that may be used in combination.

The various emissive and non-emissive layers and arrangements disclosed herein may use different materials. Examples of suitable materials are disclosed in U.S. patent application publication No. 2017/0229663, which disclosure is incorporated by reference in its entirety.

Conductive dopants:

The charge transport layer may be doped with a conductive dopant to substantially change its charge carrier density, which in turn will change its conductivity. Conductivity is increased by the generation of charge carriers in the host material and, depending on the type of dopant, a change in the fermi level (FERMI LEVEL) of the semiconductor can also be achieved. The hole transport layer may be doped with a p-type conductivity dopant, and an n-type conductivity dopant is used in the electron transport layer.

HIL/HTL：

The hole injection/transport material used in the present invention is not particularly limited, and any compound may be used as long as the compound is generally used as a hole injection/transport material.

EBL：

An Electron Blocking Layer (EBL) may be used to reduce the number of electrons and/or excitons that leave the emissive layer. The presence of such a barrier layer in a device may result in substantially higher efficiency and/or longer lifetime than a similar device lacking such a barrier layer. Furthermore, a blocking layer may be used to limit the emission to a desired area of the OLED. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and/or higher triplet energy than the emitter closest to the EBL interface. In some embodiments, the EBL material has a higher LUMO (closer to vacuum level) and/or higher triplet energy than one or more of the hosts closest to the EBL interface. In one aspect, the compound used in the EBL contains the same molecule or the same functional group as used in one of the hosts described below.

A main body:

The light-emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as a light-emitting material, and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound may be used as long as the triplet energy of the host is greater than that of the dopant. Any host material may be used with any dopant so long as the triplet criteria are met.

HBL：

A Hole Blocking Layer (HBL) may be used to reduce the number of holes and/or excitons that leave the emissive layer. The presence of such a barrier layer in a device may result in substantially higher efficiency and/or longer lifetime than a similar device lacking the barrier layer. Furthermore, a blocking layer may be used to limit the emission to a desired area of the OLED. In some embodiments, the HBL material has a lower HOMO (farther from the vacuum level) and/or higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (farther from the vacuum level) and/or higher triplet energy than one or more of the hosts closest to the HBL interface.

ETL：

An Electron Transport Layer (ETL) may include a material capable of transporting electrons. The electron transport layer may be intrinsic (undoped) or doped. Doping may be used to enhance conductivity. Examples of the ETL material are not particularly limited, and any metal complex or organic compound may be used as long as it is generally used to transport electrons.

Charge Generation Layer (CGL)

In tandem or stacked OLEDs, CGL plays a fundamental role in performance, consisting of n-doped and p-doped layers for injecting electrons and holes, respectively. Electrons and holes are supplied by the CGL and the electrode. Electrons and holes consumed in the CGL are refilled with electrons and holes injected from the cathode and anode, respectively; subsequently, the bipolar current gradually reaches a steady state. Typical CGL materials include n and p conductivity dopants used in the transport layer.

The fabrication process of Organic Light Emitting Diode (OLED) devices generally involves a packaging process. Encapsulation is used to protect organic materials from oxygen, moisture and other impurities by encapsulating the device within an oxygen and water vapor impermeable barrier. Various encapsulation methods have been developed for rigid and flexible substrates utilizing glass, metal or polymeric based barrier materials. For successful encapsulation, the sealing surfaces must be clean and free of contaminants. This can be a challenge when Organic Vapor Jet Printing (OVJP) is used to create the organic layers of an OLED. OVJP prints multiple rows of organic thin film features aligned with sub-pixels on a substrate. The process requires a lead-out margin at the beginning of each row to stabilize material deposition and a lead-out margin at the end of each row to terminate the row. Such derived edges may overlap with the package edges, especially in narrow-frame devices. Thus, OVJP may deposit some organic vapor in the sealing region of the package margin. Embodiments of the disclosed subject matter provide an apparatus that can remove deposited organic layers to achieve cleanliness of the packaging process. Embodiments of the disclosed subject matter will remove the organic deposition layer without causing redeposition of ablated material on the substrate during the cleaning process.

Compared to Liquid Crystal Displays (LCDs), OLED display technology introduces significant advantages of wider viewing angles, higher brightness and contrast. However, the thin film layers in OLED displays often need to be properly packaged to maintain the performance of the OLED display over a long lifetime of at least 10,000 hours. OLED devices can be packaged to avoid permeation of oxygen and air that may damage organic materials used in device production. Encapsulation also prevents oxygen and air from penetrating to the cathode, which is a chemically reactive metal electrode layer in an OLED device. The target permeation value for sealing the OLED device by encapsulation was less than 1 x 10 ^-6g/m² days for water vapor and 1 x 10 ^-5-1×10^-3cm³/m² days for oxygen. These specifications are much more stringent than the sealing requirements of TFT and LCD technology, which require water vapor transmission rates of 1 x 10 ^-3g/m² days and 1 x 10 ^-1g/m² days, respectively.

The encapsulation method to achieve these target permeation values may vary depending on the substrate material used in the OLED display. Rigid substrates are typically sealed using glass or metal covers with low permeability epoxy adhered thereto, while flexible displays typically use thin film permeability barriers with single or multiple organic and/or inorganic layers deposited onto the substrate using thin film deposition methods such as sputtering, atomic Layer Deposition (ALD), plasma Enhanced Chemical Vapor Deposition (PECVD), and the like.

The transport of water vapor or oxygen through the encapsulation layer may occur at micro-defects that may form during the deposition process, at imperfect interfaces between the layer and the substrate, and at gaps caused by entrained particles in the sealing surface. The cleanliness and surface roughness of the display boundaries outside the working area may be configured to allow UV-cured frit-adhesive sealing and/or to avoid defects in the interface between encapsulation layers that may cause lateral penetration. If the sealing epoxy of the barrier cap is applied over the OLED organic layer, water vapor and oxygen may diffuse through the organic material under the seal, resulting in premature display failure.

The evaporation process commonly used in the production of OLED displays involves depositing a light-emitting organic material on a substrate in a vacuum chamber, where the evaporated organic molecules are stencil printed through a thin metal mask placed over the working area of the substrate. Although the fine openings in the thin metal mask may direct a large portion of the organic material to specific areas on the grid, some organic molecules may deposit on the inactive outer boundaries of the panel and cause undesirable deposition in the sealing surface. For OVJP deposition, the lead-in and lead-out areas of the deposition line may interfere with the sealing of the lid. It is desirable to eliminate any thin film coating in the sealing area to improve the effectiveness of the package.

Embodiments of the disclosed subject matter provide an apparatus that allows a focused laser beam to be transmitted at a boundary section of an OLED display and to remove a plume of organic material generated by laser ablation. An example plume removal device according to an embodiment of the disclosed subject matter is shown in fig. 3. The laser source providing the laser beam 107 may provide short or ultra-short pulses of wavelengths that may correspond to the absorption characteristics of the organic material through the beam delivery cavity 105 to achieve optimal vapor generation. This may be in the infrared or ultraviolet region of the electromagnetic spectrum. The beam delivery cavity 105 may be empty or filled with optically transparent blocks. For example, the optically transparent block may be formed of a sapphire material. The plume removal device 103 is positioned away from the substrate 102 such that the bottom surface of the plume removal device 103 is parallel to or facing the substrate 102 and the center of the Heat Affected Zone (HAZ) 100 is aligned with the surface of the organic matter 101 to be ablated. In one embodiment, the bottom surface of the plume removal device 103 faces the substrate in any orientation suitable for removal of chamber gases 106 through the exhaust passage 104. For example, the bottom surface may be substantially parallel to the surface or angled with the surface to be non-parallel to the surface (i.e., the bottom surface is at an angle of 0-90 degrees relative to the surface).

In one embodiment, the plume removal device 103 may be circular, as shown. In alternative embodiments, the plume removal device 103 may be any shape. In addition, as shown, the beam delivery cavity/block 105 is circular. In alternative embodiments, the beam delivery cavity/block 105 may be any shape. In one embodiment, the overall shape of the beam delivery cavity/block 105 may be similar to the shape of the plume removal device 103. In an alternative embodiment, the beam delivery cavity/block 105 may be different from the shape of the plume removal device 103.

Ablation using the plume removal device 103 may be performed in a vacuum chamber filled with an inert chamber gas 106 at a controlled pressure level. For example, the inert chamber gas 106 may be nitrogen, carbon dioxide, and/or argon, and/or any other gas known in the art. Plume removal device 103 may have an internally machined network of micro-channels that extract organic vapors generated by ablation with a chamber gas stream. Organic vapors from ablation may be removed from the chamber through an exhaust conduit connected to the exhaust passage 104. The proximity of the bottom surface of the plume removal device 103 to the organic layer 101 on the substrate 102 may cause a layer of chamber gas flow 106 along the plane of the substrate 102. The radial inflow of chamber gases towards the outlet aperture of the plume removal device 103 minimizes the escape of organic vapors to the non-ablated section of the substrate 102 and avoids post-deposition by trapping the generated plumes. The short pulse laser produces a small HAZ region 100 in the organic layer 101 and thermal conduction in the substrate 102 can be minimized. Plume removal device 103 may be machined from aluminum or steel and/or other suitable materials with low emissivity. Plume removal device 103 may be heated with an external heater to a temperature level above the sublimation temperature of the material being ablated to avoid clogging of the internal channels.

The plume removing device may be a device that extracts organic vapor generated by ablating a HAZ region of the substrate by the laser beam using a chamber gas flow. The plume removal device may be positioned away from the substrate to induce a symmetric flow pattern in the gap between the substrate and the plume removal device, and may uniformly divert the flow to the exhaust port of the plume removal device. The plume removal device may be configured to allow the laser beam from the laser source to create an ablation pattern with minimal interaction with the generated plume. The velocity of the carrier gas flow in the direction of the vent of the plume removal device may be sufficient to capture material in the plume created by the ablation prior to redeposition on the surface of the substrate. The carrier and exhaust flows may be a function of the exhaust pressure values achieved, the area of the exhaust holes, and the distance between the substrate and the lower surface of the plume removal device.

The plume removal process may be represented in a computer simulation using Computational Fluid Dynamics (CFD). The simulation may use a plume removal device 202 and corresponding dimensions as shown in fig. 4. The laser beam may produce a circular HAZ pattern 201 of 0.5mm diameter, where the individual pulse diameters may be in the range between 50 and 100 microns. The organic vapor productivity at the HAZ pattern 201 on the organic layer 203 may be 0.16g/s (g/s), which may be a representative value of the evaporation rate at 300 ℃. These values may vary depending on the nature of the material. The provision of a vent pump at the outlet 205 of the plume removal device 202 may result in a flow rate of 100sccm (standard cubic centimeters per minute). The temperature may be controlled to be not lower than the sublimation temperature of the material being ablated. The inlet chamber gas 204 may be provided at 200 torr (chamber pressure) and 20 deg.c. The distance between the bottom surface of the plume removal device 202 and the organic layer 203 may always be referred to as the Fly Height (FH). In this example, the Flying Height (FH) may be set to 0.5mm.

Laser ablation of organic materials in the HAZ may experience a temperature change 301 as shown in fig. 5 that produces a molar flux 302 during the ablation duration of the laser, where dt = 0.1s, where dt is the change in time (seconds). Fig. 6A shows that the plume generation rate at the HAZ may follow a time step change corresponding to the profile of the laser pulse. After a short delay in the onset of plume initiation, the rate of vapor removal at the outlet end of the device was observed. The amount of material removed under these conditions modeled in the CFD simulation indicated that the plume removal device was 99.9% effective in removing the vapor generated. In the example shown in fig. 6A, the flight height may be 500 μm, mp· (i.e., ablation rate) may be 0.16g/s, tp (i.e., temperature of ablated material) may be 300 ℃, tw (i.e., temperature of the plume removal device) may be 250 ℃, and Q (i.e., exhaust flow rate) may be 100sccm. As predicted by CFD simulation, the organic vapor removal efficiency may vary with the exhaust flow rate Q maintained at a given fly height value FH. Extremely high flow rates (Q > >100 sccm) may be undesirable because undesirable deposition of organic materials in the interior channel walls of the device may occur due to excessive cooling provided by the chamber gases. However, CFD simulations have shown that 100% efficiency can be maintained even at low flow rates of 60sccm as for FH <2mm and even at 20sccm at FH <1mm, as shown in fig. 6B.

Fig. 7 shows a cross-sectional view of the flow field between the plume removal device and the organic layer and the internal flow channels 501-504. The concentration of the organic vapor is represented in gray scale, and the arrows show the direction of the vapor flux. 501 corresponds to the time immediately after initiation of plume generation. 502 shows the plume entering the outlet aperture facing the vapor source and being biased towards the outlet end. 503 shows that plume transport continues after the laser pulse is removed and vapor generation is stopped. 504 correspond to a period of time exceeding the period of the laser pulse, wherein most of the flux transmission occurs within the internal channels of the device.

Fig. 8 shows a substrate 601 that can be linearly translated at a speed to create a series of HAZ sites 605 on an organic layer 602 of the substrate 601 while a laser source 604 follows a circular pattern to cover an area larger than the individual laser pulse diameters. This can also be achieved by moving the plume removal device 603 and the external laser source unit in opposite directions along the platform carrying the substrate 601 while keeping the substrate stationary. With respect to plume removal device 603, the heating and vapor generation profile at the haz may follow a temporal pattern 606 that is approximately constant in time. Such conditions may be represented by steady state CFD simulations, where the vapor source may remain the same over time.

Fig. 9 shows the flow pattern of the chamber gas. 701 shows nitrogen entering from the outer edge of the plume removal device and travelling along the plane of the substrate and exiting vertically towards the outlet on the opposite end of the device. 702 shows a flux profile similar to the organic vapor shown in 502 of fig. 7, which is maintained during periods of relative movement of the cover substrate with respect to the device. In fig. 9, the flying height may be 500 μm and Q may be 20sccm.

In some embodiments, the plume removal device may be a radially outward delivery flow device, wherein the flow is from the center of the plume removal device and extends radially outward. For example, fig. 14 shows a plume removal device similar to that of fig. 3, but with radially outward delivery flow according to an embodiment of the disclosed subject matter. In other embodiments, the plume removal device may have a cross-flow configuration. For example, fig. 15 shows a plume removal device having a cross-flow configuration, and fig. 16 shows a different view of the plume removal device having a cross-flow configuration. In the case of a cross-flow configuration, the flow sweeps across the Heat Affected Zone (HAZ) from the inlet to the exhaust.

Fig. 10 shows Fly Height (FH) sensitivity, where CFD analysis can be repeated for varying FH values in the range of 20 to 60 microns. 801 corresponds to the closest position of the plume removal device against the substrate, with the highest concentration value at the source. 802 and 803 correspond to the situation where the device is raised to a higher FH value and a lower vapor concentration is accumulated at the source. 801 shows that flow in the gap between the plume removal device and the substrate can be restricted and that a minimum FH value is established based on the characteristics of the organic layer surface to be cleaned.

Similarly, the pumping at the outlet end of the plume removal device may be tailored to the material removal needs of a particular cleaning process. Fig. 11 shows that the amount of flow rate generated at the exhaust of the plume removal device may not be sufficient to direct all of the vapor flux generated at the ablated region 901. The minimum flow rate for capturing all generated vapor without undesirable post-deposition can be established similar to the determination of the fly height of the plume removal device.

Fig. 12 shows another embodiment of the plume removal device with an additional internal outlet channel 1001 and with four channels connecting the vent radially to a machined groove 1002 on the periphery of the plume removal device. When the outer ring 1003 is placed around the plume removal device, the grooves 1002 may act as a manifold for the mixture of organic vapor and chamber gas and exit the assembly at a single outlet 1004. The outer ring 1003 may be used to mount the assembly to a frame that adjusts the relative position of the plume removal device with respect to the substrate. An optical device comprising a lens, a mirror and a laser source for transmitting a laser beam through the device may be accommodated in the frame. In an alternative embodiment, there may be any number of internal outlet passages.

Fig. 13 shows a cross-sectional view of an assembly utilizing four internal channels 1102 connected to a single annular vent slot 1101 of the device. Additional vent slots 1103 may be machined around the inner hole 1101 to capture any vapor that cannot be extracted by the inner hole slots. The additional vent slots may be radially connected to the external groove with additional channels 1104. The number of internal channels may be selected based on the takt time requirements of the display manufacturing process to achieve a certain duration of the cleaning process.

As shown in fig. 1-18, an apparatus may include: a laser source configured to output a laser beam (e.g., laser beam 107 shown in fig. 3 and/or laser beam 604 shown in fig. 8); a beam delivery cavity (e.g., beam delivery cavity 105 shown in fig. 3) that receives the output laser beam on a first side of the device and outputs the laser beam on a second side of the device, wherein the first side is opposite the second side; and a plume removal device having an exhaust vent on a second side of the apparatus facing a Heat Affected Zone (HAZ). As shown in fig. 1-18, an apparatus according to an embodiment of the disclosed subject matter may include: a laser source configured to output a laser beam (e.g., laser beam 107 shown in fig. 3 and/or laser beam 604 shown in fig. 8); and a beam delivery chamber (e.g., beam delivery chamber 105 shown in fig. 3) that receives the output laser beam and outputs the laser beam to a substrate (e.g., substrate 102 shown in fig. 3 and/or substrate 601 shown in fig. 8). The beam delivery cavity may be filled with an optically transparent material. The optically transparent material may comprise a sapphire material. In one embodiment, the beam delivery cavity 105 may be sized slightly larger than the size required for the laser beam 107. In other words, there may be a small amount of space between the laser beam 107 and the beam delivery cavity/block 105. In this embodiment, in order to move the laser beam 107 over a portion of the organic layer 101 and subsequently move the HAZ 100, the entire plume removal device 103 is moved. In an alternative embodiment, the beam delivery cavity 105 may be sized to be much larger than the size required by the laser beam 107. In other words, there may be a large amount of space between the edge of the laser beam 107 and the edge of the beam delivery cavity/block 105. In this embodiment, to move the laser beam 107 over a portion of the organic layer and subsequently move the HAZ 100, only the laser beam 107 is moved inside the beam delivery cavity/block 105 while the remainder of the plume removal device 103 remains stationary relative to the laser beam 107. In yet another embodiment, both the plume removal device 103 and the laser beam 107 may be stationary and the substrate 102/organic layer 101 moves relative to the plume removal device 103 and the laser beam 107. In yet another embodiment, any combination of the previous embodiments may be used simultaneously to orient the HAZ 100 over different portions of the organic layer 101.

In one embodiment, when the beam delivery cavity 105 is circular, the beam delivery cavity 105 has a diameter of 1mm to 3 mm. In one embodiment, when the beam delivery cavity 105 is elliptical, the minor axis of the ellipse may be between 1mm and 3mm in length, and the major axis of the ellipse may be between 1mm and 3mm in length. In one embodiment where the beam delivery cavity 105 is not circular, the beam delivery cavity 105 may have a minimum gap of 450 microns between the inner edge of the beam delivery cavity and the laser beam 107.

The apparatus may include a plume removal device (e.g., plume removal device 103 shown in fig. 3 and/or plume removal device 603 shown in fig. 8) having an exhaust hole adjacent to a Heat Affected Zone (HAZ) on the substrate (e.g., HAZ 100 shown in fig. 3 and/or HAZ site 605 shown in fig. 8) and disposed at an initial predetermined distance from the substrate, wherein a bottom surface of the plume removal device is parallel to or facing the substrate, wherein an organic substance (e.g., organic layer 101 shown in fig. 3 and/or organic layer 602 shown in fig. 8) is disposed on the substrate and the HAZ is aligned with a surface of the substrate having the organic substance to be ablated by the laser beam.

The size of the feature of the organic material to be removed by ablation with a laser beam is greater than or equal to 1mm. The laser beam output by the laser may be configured to produce a pattern in the HAZ, and at least one pulse of the laser beam may have a diameter of 50-100 microns. The pattern may be circular, linear, etc. In an example circular pattern, the diameter may be 0.5mm or any suitable size.

The apparatus may be disposed in a vacuum chamber (e.g., an inert gas having a pressure level controlled by a controller). The vacuum chamber may have a pressure of 200 torr and/or other suitable pressure. The vacuum chamber may include a chamber gas (e.g., chamber gas 106 shown in fig. 3), which may be nitrogen. The vacuum chamber may be an oxygen-free and water-free environment. The plume removal device may include an internal network of micro-channels configured to utilize the inert gas flow of the chamber to extract organic vapors formed by laser beam ablation. The apparatus may include an exhaust source in fluid communication with an exhaust channel (e.g., exhaust channel 104 shown in fig. 3) configured to remove inert gas and ablated material from the chamber. The exhaust source may have a lower pressure than the chamber environment. The plume removal device may be configured to have a radial inflow of inert gas from the chamber towards the outlet aperture of the plume removal device. This configuration can be used to minimize the escape of organic vapors to the non-ablated section of the substrate and to trap the plume. The plume removal device may be disposed at a predetermined distance from the substrate and may be configured to cause inert gas of the chamber to flow along the plane of the substrate. The plume removal device may be formed of steel, aluminum, and/or any other suitable material.

The organic plume removal device may have different configurations for the internal fluid flow channels, where the delivery channels as shown in fig. 15 may introduce inert gas into the chamber at a controlled delivery flow rate. The delivery gas may mix with the chamber gas and organic vapor generated at the HAZ before being captured by the exhaust channel of the device. The device may be maintained at a pressure lower than the chamber pressure corresponding to the controlled exhaust flow rate.

Details of this plume device configuration are shown in fig. 16, the delivery holes and exhaust holes may be in the form of rectangular slots rather than circular rings as shown in the previous configuration. In such a configuration, the laser beam delivery lumen and/or block may be positioned between the delivery slot and the vent slot to create a unidirectional flow through the laser ablation zone. This may improve the organic vapor removal efficiency of the device compared to other configurations without delivery channels and holes.

The substrate may be planar and may have variations in surface topography. The substrate may be disposed on a stage, and the stage may be spaced apart from the laser source. The substrate may be mounted on a stage configured to linearly translate at a predetermined rate. The laser, the beam delivery cavity, and the plume removal device may be configured to be movable in a direction opposite to the linear translation of the platform. The substrate may be mounted on a stage and the laser, beam delivery chamber and plume removal device may be configured to be movable relative to the stage, which may be configured to be stationary.

In some embodiments, the substrate may have a first side and a second side, and the organic substance is disposed on the first side. The laser source may be spaced apart from the substrate to be closer to the second side of the substrate, and the plume removal device and the beam delivery chamber may be spaced apart from the substrate to be closer to organic matter disposed on the first side of the substrate. In some embodiments, the plume removal device, the beam delivery chamber, and the laser source may be spaced apart from the substrate to be closer to organic matter disposed on the first side of the substrate.

The flying height between the bottom surface of the plume removing device and the organic layer may be 50 μm to 1mm. The apparatus may include a sensor configured to detect a change in a surface height of an organic substance disposed on a substrate, and a controller to control a flying height between a bottom surface of the plume removal device and the organic layer based on the detected change.

The apparatus may include at least one heater configured to heat the plume removal device. For example, fig. 17 shows a plume removal device of an apparatus with a heater. The apparatus may include a cold plate disposed above a platen configured to hold a substrate, wherein the cold plate includes a window configured to allow a laser beam to pass through. The cold plate and plume removal device may be mounted on the same frame that is disposed above and separate from the platform holding the substrate. Fig. 17-18 show an example configuration of an apparatus having a plume removal device comprising a cold plate. The window may be a slit configured to allow the laser beam to pass through. The window may be configured to allow organic matter ablated by the laser beam to pass towards the plume removal device.

The apparatus may include a thermal shield disposed above a platform configured to hold a substrate, wherein the thermal shield includes a window configured to allow a laser beam to pass through. Figures 17-18 show an example plume removal device of an apparatus comprising a top insulating panel and a bottom insulating panel. The window of the thermal shield may be configured to allow organic matter ablated by the laser beam to pass toward the plume removal device. That is, the window of the insulating plate may be configured to allow the plume removal device to be in fluid communication with the plume and the substrate. The thermal shield and plume removal device may be mounted on the same frame that is disposed above and separate from the platform holding the substrate. The window may include a cutout configured to allow the laser beam to pass through. The window may be configured to allow organic matter ablated by the laser beam to pass towards the plume removal device.

The apparatus may include a plurality of channels connected to at least one vent slot of the plume removal device. In some embodiments, the apparatus may include a plurality of channels connected to a plurality of vent slots of the plume removal device, wherein the plurality of vent slots are radially connected. In some embodiments, as shown in fig. 17, the plume removal device may include a delivery gland to introduce inert gas into the chamber, and a vent gland to remove inert gas and ablated material from the chamber.

In one embodiment, a laser film removal process may be deployed to separate the lines printed by OVJP into discrete pixels, as shown in fig. 19. A display backplane is depicted with electrodes 1901 such that each electrode may correspond to a different subpixel. The electrodes may have printed thereon lines of blue 1902, green 1903, and red 1904 of a printed emissive layer extending between pixels to cover adjacent subpixels of the same color. In one embodiment, the emissive layer color combination may be any color and/or any combination of colors. For example, as shown herein, the lines are blue (B), green (G), and red (R), which are then repeated. Or the lines may be BGBG, BGRGB, BBGR or any other combination of printed lines. The left-hand array may be before the laser film removal and the right-hand array may be after the laser film removal of at least a portion of the emissive layer. A series of laser ablations performed by plume removal device 103 may span the printed line cut between 1905 pixels, such that the printed film covering each electrode is disconnected from its neighbors. Each sub-pixel may be surrounded on all sides by the perimeter of the unprinted back plate. Here, such an architecture may be advantageous because it facilitates adhesion of the thin film encapsulant to the substrate by creating clean attachment points between the electroactive subpixels. In one embodiment, each electrode and its associated remaining emissive layer may be isolated from any other electrode as shown. In an alternative embodiment, the electrodes and their associated remaining emissive layers may be connected to other emissive layers, not shown. In other words, the plume removal device 103 may remove some of the emissive layers but not others of the emissive layers such that each emissive layer, which is now a smaller portion, need not be located over only a single electrode.

One embodiment of a plume removal system for use with the present application is depicted in fig. 20. In this embodiment, one or more bar-shaped plume removal devices 2001 are depicted. A pair of plume removal devices is depicted here, but other configurations are possible. The devices may each have a linear array of vents 2002 facing the substrate and may be configured to optimize removal of the vapor plume created by the ablated material from each printed line. The laser beam 2003 may be scanned along the length 2004 of the strip, passing through each printed line as it is scanned. The laser is depicted as scanning the gap between two bars, but other locations are possible for the laser. The laser beam may be scanned or stopped at a steady rate over each segment of line to be ablated. The plume removal device may be moved relative to the substrate in the same direction 2005 as the line printing by the OVJP process, allowing the two processes to be placed in series.

It should be understood that the various embodiments described herein are by way of example only and are not intended to limit the scope of the invention. For example, many of the materials and structures described herein may be substituted with other materials and structures without departing from the spirit of the invention. The invention as claimed may thus include variations of the specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. It should be understood that the various theories as to why the present invention works are not intended to be limiting.

Claims (15)

1. An apparatus, comprising:

a laser source configured to output a laser beam;

A beam delivery cavity to receive an output laser beam on a first side of the device and output the laser beam on a second side of the device, wherein the first side is opposite the second side; and

Plume removal means having an exhaust hole on the second side of the apparatus facing the heat affected zone, HAZ.

2. The apparatus of claim 1, wherein the beam delivery cavity is filled with an optically transparent material.

3. The apparatus of claim 2, wherein the optically transparent material comprises a sapphire material.

4. The apparatus of claim 1, wherein a bottom surface of the plume removal device faces a substrate, wherein an organic substance is disposed on the substrate, and the HAZ is aligned with a surface of the substrate having the organic substance to be ablated by the laser beam.

5. The apparatus of claim 4, further comprising:

a cold plate disposed above a platen configured to hold the substrate,

Wherein the cold plate comprises a window configured to allow the laser beam to pass through.

6. The apparatus of claim 5, wherein the cold plate and the plume removal device are mounted on the same frame disposed above and separate from the platform holding the substrate.

7. The apparatus of claim 5, wherein the window comprises a cutout configured to allow the laser beam to pass through, and is configured to allow the organic matter ablated by the laser beam to pass through the plume removal device.

8. The apparatus of claim 4, further comprising:

A thermal shield disposed over a platform configured to hold the substrate,

Wherein the heat shield includes a window configured to allow the laser beam to pass through, and

Wherein the window of the thermal shield is configured to allow the organic matter ablated by the laser beam to pass through the plume removal device.

9. The apparatus of claim 8, wherein the thermal shield and the plume removal device are mounted on the same frame disposed above and separate from the platform holding the substrate.

10. The apparatus of claim 8, wherein the window comprises a cutout configured to allow the laser beam to pass through, and is configured to allow the organic matter ablated by the laser beam to pass through the plume removal device.

11. The apparatus of claim 4, wherein a flying height between a bottom surface of the plume removal device and the organic substance is 50 μιη to 1mm.

12. The apparatus of claim 4, further comprising:

A sensor configured to detect a change in a surface height of the organic substance disposed on the substrate; and

A controller to control a flying height between a bottom surface of the plume removing device and the organic substance based on the detected change.

13. The apparatus of claim 4, wherein the substrate is disposed on a stage, and wherein the stage is spaced apart from the laser source.

14. The apparatus of claim 1, further comprising:

a plurality of channels connected to at least one vent slot of the plume removal device.

15. The apparatus of claim 1, further comprising a plurality of channels connected to a plurality of vent slots of the plume removal device, wherein the plurality of vent slots are radially connected.