Organic vapor jet printing system

Abstract

This application relates to an organic vapor jet printing system. Systems and methods for depositing materials on a substrate via OVJP are provided. A float table and a gripper are used to move and position the substrate relative to one or more OVJP print bars to reduce the chance of damaging or compromising the substrate or previously deposited materials.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims priority to U.S. Patent Application No. 63 / 126,475, filed December 16, 2020, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present invention relates to devices and techniques for making organic emissive devices, such as organic light emitting diodes, and devices and techniques comprising the same. BACKGROUND

[0004] Opto-electronic devices that make use of organic materials are becoming increasingly important for a number of reasons. Many of the materials used to make such devices are relatively inexpensive, so organic opto-electronic devices have the potential to be lower cost than alternative devices that use expensive materials. In addition, the inherent properties of organic materials, such as their flexibility, can make them well suited for particular applications such as fabrication on a flexible substrate. Examples of organic opto-electronic devices include organic light emitting diodes / devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic light absorbing detectors. For OLEDs, the organic materials can have performance advantages over conventional materials. For example, the light generating layer(s) of an OLED can easily be tuned to emit light of different

[0005] OLEDs make use of thin organic films that emit light when a voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in the display, lighting, and back-lighting applications. 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.

[0006] One application for phosphorescent emission is a full color display. Industry standards for such displays require that the pixels be appropriate for emitting particular colors, known as “saturated” colors. Specifically, these standards require saturated red, green, and blue pixels. Alternatively, an OLED can be designed to emit white light. In conventional liquid crystal displays, absorbing color filters are used to filter the emissions from a white backlight to produce red, green, and blue emissions. The same technology can also be used for OLEDs. A white OLED can be a single emissive layer (EML) device or a stacked structure. Color can be measured using CIE coordinates, which are well known in the art.

[0007] As used herein, the term "organic" includes polymeric and small molecule organic materials, which can be used to fabricate organic light emitting devices. "Small molecules" refer to any organic materials that are not polymers, and "small molecules" can actually be quite large. In some cases, small molecules can include repeating units. For example, a molecule that contains a long chain alkyl group can not be removed from the "small molecule" category, even though it can actually be quite large. Small molecules can also be incorporated into polymers, for example, as a pendant group on a polymer backbone or as a part of the backbone. Small molecules can also serve as the core moiety of a dendrimer, which itself can be a small molecule. Dendrimers with a small molecule core can be "small molecules" and are included within the meaning of "small molecules" as used herein.

[0008] As used herein, "top" means farthest from the substrate, and "bottom" means closest to the substrate. When a first layer is described as "disposed on" a second layer, the first layer is positioned farther from the substrate. Unless specified that a first layer is "in contact with" a second layer, there can be other layers between the first and second layers. For example, a cathode can be described as "disposed on" an anode even though various organic layers are between the cathode and the anode.

[0009] As used herein, "solution processible" means capable of being dissolved, dispersed, or transported in and / or deposited from a liquid medium, either in solution or suspension form.

[0010] A ligand can be referred to as "photoactive" when it is believed to directly contribute to the photoactive properties of an emissive material. A ligand can be referred to as "auxiliary" when it is believed not to contribute to the photoactive properties of an emissive material, although an auxiliary ligand can alter the properties of a photoactive ligand.

[0011] As used herein, and as will be understood by one of ordinary skill in the art, a first "highest occupied molecular orbital" (HOMO) or "lowest unoccupied molecular orbital" (LUMO) energy level is "greater than" or "higher than" a second HOMO or LUMO energy level if the first energy level is closer to the vacuum energy level. Since ionization potential (IP) is measured as a negative energy with respect to the vacuum energy level, a higher HOMO energy level corresponds to a smaller absolute value of IP (a less negative IP). Similarly, a higher LUMO energy level corresponds to a smaller absolute value of electron affinity (EA) (a less negative EA). On a conventional energy level diagram, with the vacuum energy level at the top, a LUMO energy level of a material is higher than a HOMO energy level of the same material. A "higher" HOMO or LUMO energy level is thus manifested by a closer proximity to the top of such diagram.

[0012] As used herein, and as will be generally understood by one of ordinary 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 functions are typically measured as negative numbers relative to the vacuum energy level, this means that a "higher" work function is more negative. On a conventional energy level diagram with the vacuum energy level at the top, a "higher" work function is illustrated as being further away from the vacuum energy level in the downward direction. Thus, the definitions of HOMO and LUMO energy levels follow a different convention than work functions.

[0013] Layers, materials, regions, and devices can be described herein with reference to the color of light they emit. Generally, as used herein, an emissive region described as producing a particular color of light can include one or more emissive layers disposed in a stacked manner over one another.

[0014] 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 580-700 nm or that has the highest peak of its emission spectrum 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; a "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 that has an emission spectrum with a peak wavelength in the range of about 540-600 nm. In some arrangements, separate regions, layers, materials, regions, or devices can provide separate "deep blue" and "light blue" light. As used herein, in arrangements that provide separate "light blue" and "deep blue" components, the "deep blue" component refers to a component with a peak emission wavelength that is at least about 4 nm 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 465-500 nm, and the peak emission wavelength of the "deep blue" component is in the range of about 400-470 nm, although these ranges can vary for some configurations. Similarly, a color conversion layer refers to a layer that converts or modifies light of one color to light having a wavelength specified for that color. For example, a "red" color filter refers to a filter that forms light having a wavelength in the range of about 580 nm to about 700 nm. Generally, there are two categories of color conversion layers: color filters that modify the spectrum of light by removing non-desired wavelengths of light, and color conversion layers that convert higher energy photons to lower energy. The component of "color" refers to a component that, when activated or in use, produces or otherwise emits light having a particular color as previously described. For example, "a first emissive region of a first color" and "a second emissive region of a second color different from the first color" describe two emissive regions that emit two different colors as previously described when activated within a device.

[0015] As used herein, emissive materials, layers, and regions can be distinguished from one another, and from other structures, based on the light that is initially generated by the material, layer, or region, rather than the light that is ultimately emitted by the same or different structure. Initial light generation is typically the result of an energy level change that results in photon emission. For example, an organic emissive material can initially generate blue light, which can be converted to red or green light by a color filter, quantum dot, or other structure, such that the complete emissive stack or sub-pixel emits red or green light. In this case, the initial emissive material or layer can be referred to as a "blue" component, even though the sub-pixel is a "red" or "green" component.

[0016] In some cases, it can be preferable to describe the color of a component, such as an emissive region, sub-pixel, color conversion layer, etc., in terms of 1931 CIE coordinates. For example, a yellow emissive material can 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 term also corresponds to a shape in the 1931 CIE coordinate color space. A shape in the 1931 CIE color space is constructed by following the locus between two color points and any other interior point. For example, the interior shape parameters for red, green, blue, and yellow can be defined as follows:

[0017]

[0018] More 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. SUMMARY

[0019] According to embodiments, an organic light emitting diode / device (OLED) is also provided. The OLED can include an anode, a cathode, and an organic layer disposed between the anode and the cathode. According to embodiments, the organic light emitting device is incorporated into one or more devices selected from the group consisting of: a consumer product, an electronic component module, and / or a lighting panel.

[0020] Embodiments disclosed herein provide a deposition system including one or more print bars, which can be OVJP-type print bars, each of which includes one or more print heads, a float table including one or more substrate clamps configured to hold a substrate and adjust the position of the substrate on the float table in at least two degrees of motion, and one or more controls arranged to provide control over the one or more substrate clamps. The system can include one or more sensors to measure the alignment of a substrate on the float table with the one or more OVJP print bars. The float table can extend across the system such that it extends in front of and behind the print bars, or the float table can move in a zone that extends beneath the one or more OVJP print bars. The substrate can be moved on the float table independently of the movement of the float table beneath the one or more OVJP print bars, for example to allow for fine positioning of the substrate on the float table.

[0021] Embodiments also provide methods of operating a deposition system by obtaining a substrate, placing the substrate on a float table and securing and adjusting the position of the substrate using one or more clamps. The float table and / or the substrate can be moved through the system, or the substrate can be moved across the float table to move it through a zone beneath a print bar (e.g., an OVJP print bar in a deposition system). While the substrate is moved through the system, material to be deposited on the substrate can be ejected from the print bar. After deposition, the float table and / or the substrate can be moved to a position where the substrate is not located beneath the print bar. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 An organic light emitting device structure that can be manufactured using the apparatus and techniques disclosed herein is shown.

[0023] Figure 2 An example structure of an inverted organic light emitting device without a separate electron transport layer as can be manufactured using the apparatus and techniques disclosed herein is shown.

[0024] Figure 3A An example of a print engine as disclosed herein is shown.

[0025] Figure 3B An example of a system using a print bar with multiple print engines operating at the print head level as disclosed herein is shown.

[0026] Figure 3C An example of a system using a single print engine operating at the print bar level as disclosed herein is shown.

[0027] Figure 3D An exploded view of a die manifold, heat shield, and related components as disclosed herein is shown.

[0028] Figure 3E and 3F An example arrangement of print bars as disclosed herein is shown.

[0029] Figure 4A and 4B A top-down view and a side view of an example OVJP deposition system according to embodiments disclosed herein are shown, respectively.

[0030] Figure 4C A top view, a side view, and a front view of a substrate PV station according to embodiments disclosed herein are shown.

[0031] Figure 4D A front view of an OVJP system as shown in Figures 4A-4C is shown disposed in a vacuum chamber according to embodiments disclosed herein.

[0032] Figure 4E An example OVJP system according to embodiments disclosed herein is shown, wherein print bars are immersed in a PV station.

[0033] Figure 5A and 5B A side view and a front view of an arrangement according to embodiments disclosed herein are shown, respectively, wherein a substrate and print bars are flipped vertically compared to those shown in Figures 4A-4E

[0034] An example deposition system according to embodiments disclosed herein is shown, wherein a substrate enters with the active side down, and wherein the substrate moves on a stationary PV station that extends through the system. Figure 6

[0035] An example system according to embodiments disclosed herein is shown, similar to the system shown in Figure 7 , wherein a substrate is positioned with the active side up. Figure 6

[0036] An example deposition system according to embodiments disclosed herein is shown, wherein a substrate is arranged with the active side down, similar to the example shown in Figure 8 , wherein the non-active backside of the substrate is held by a top PV station. Figure 6

[0037] Figure 9 A front view of an example deposition system according to embodiments disclosed herein is shown, wherein a substrate is not supported on a gas table as shown in Figure 6 and 7 when entering the system, but is held from above by a vacuum chuck or similar device with the active side down. DETAILED DESCRIPTION

[0038] ​Generally, an OLED comprises 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(s). The injected holes and electrons each migrate toward the oppositely charged electrode. When an electron and hole localize on the same molecule, an "exciton," which is a localized electron-hole pair having an excited energy state, is formed. When the exciton relaxes, it releases energy that can take the form of light (photoluminescence), heat (radioluminescence) or sound (sonoluminescence). In some cases, the exciton can be localized on an excimer or an exciplex. Non-radiative mechanisms (e.g. thermal relaxation), can also occur, but are generally considered undesirable.

[0039] Initial OLEDs used emitters that emitted from a singlet state ("fluorescence"), as disclosed, for example, in U.S. Patent No. 4,769,292, which is incorporated by reference in its entirety. Fluorescent emission generally occurs in time frames of less than 10 nanoseconds.

[0040] More recently, OLEDs having emitters that emit light from a triplet state ("phosphorescence") have been demonstrated. Baldo et al., "Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices," Nature, vol. 395, 151-154, 1998 ("Baldo-I"); and Baldo et al., "Very high-efficiency green organic light-emitting devices based on electrophosphorescence," Appl. Phys. Lett., vol. 75, no. 3, pp. 4-6 (1999) ("Baldo-II"), which are incorporated by reference in their entireties. Phosphorescence is described in more detail in U.S. Patent No. 7,279,704, column 5-6, which is incorporated by reference.

[0041] Figure 1An organic light emitting device 100 is shown. The figures are not necessarily drawn to scale. The device 100 can 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 barrier layer 170. The cathode 160 is a compound cathode having a first conductive layer 162 and a second conductive layer 164. The device 100 can be fabricated by depositing the layers sequentially. The properties and functions of these various layers, as well as example materials, are described in more detail in U.S. Patent No. 7,279,704 at columns 6-10, which is incorporated by reference in its entirety.

[0042] More examples of each of these layers can be found. 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 F4-TCNQ at a mole 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. Patent 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 at a mole ratio of 1: 1, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. U.S. Patent Nos. 5,703,436 and 5,707,745, incorporated by reference in their entireties, disclose examples of cathodes comprising a compound cathode having a thin layer of metal, such as Mg:Ag, on top of a transparent, conductive, sputter-deposited ITO layer. The theory and use of blocking layers are described in greater detail in U.S. Patent No. 6,097,147 and U.S. Patent Application Publication No. 2003 / 0230980, which are incorporated by reference in their entireties. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated by reference in its entirety. Descriptions of protective layers can be found in U.S. Patent Application Publication No. 2004 / 0174116, which is incorporated by reference in its entirety.

[0043] Figure 2An inverted OLED 200 is shown. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole transport layer 225, and an anode 230. Device 200 can be fabricated by sequentially depositing the layers. Because the most common OLED configuration has a cathode disposed over an anode, and device 200 has a cathode 215 disposed under anode 230, device 200 can be referred to as an "inverted" OLED. Similar materials to those described with respect to device 100 can be used in the corresponding layers of device 200. Figure 2 One example of how some layers can be omitted in the structure of device 100 is provided.

[0044] Figure 1 and 2 The simple layered structure illustrated in FIGS. 1-3 is provided by way of non-limiting example, and it is understood that embodiments of the present application can be used in conjunction with a variety of other structures. The particular materials and structures described are exemplary in nature and other materials and structures can be used. Functional OLEDs can be obtained by combining the various layers described in different ways, or layers can be omitted entirely, based on design, performance, and cost factors. Other layers not specifically described can also be included. Materials other than those specifically described can be employed. As an example, the OLED can be fabricated such that the layers have properties as described herein, but are not constructed as described. Although many of the examples provided herein describe various layers as having a single material, it is understood that combinations of materials, such as a mixture of host and dopant, or more generally a mixture, can be used. Also, the layers can have various sub-layers. Not all of the layers of an OLED need be explicitly described herein to be considered a part of the application. 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 can be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED can be described as having an "organic layer" disposed between a cathode and an anode. This organic layer can include a single layer, or can further include multiple layers of different organic materials as described, for example, with respect to FIGS. 1-3. For simplicity, the components of the OLEDs will be described herein as provided in the order of the drawings, but other order of layers can be used and are contemplated. Figure 1 and 2 as described with respect to FIGS. 1-3.

[0045] Structures and materials other than those specifically described can also be used. For example, an OLED including a polymeric material can be employed. Polymeric OLEDs (PLEDs) have been disclosed, for example, in U.S. Patent No. 5,247,190, which is incorporated by reference in its entirety. By way of another example, an OLED can be fabricated having a single organic layer. The OLED can be stacked, as described in U.S. Patent No. 5,707,745, which is incorporated by reference in its entirety. The OLED structures can be used in a variety of applications, such as for example, in the manufacture of an OLED. Figure 1 and 2The simple layered structure illustrated in the middle is an oversimplification. For example, the substrate can include angled reflective surfaces to improve out-coupling, such as the mesa structure described in U.S. Patent No. 6,091,195 to Forrest et al., and / or the dimple structure described in U.S. Patent No. 5,834,893 to Bulovic et al., which are incorporated by reference in their entirety.

[0046] In some embodiments disclosed herein, the emissive layer or material, such as Figures 1-2 The emissive layer 135 and emissive layer 220 shown in the middle, respectively, can include quantum dots. Unless explicitly indicated to the contrary or indicated by context in accordance with the understanding of one of ordinary skill in the art, an "emissive layer" or "emissive material" as disclosed herein can include organic emissive materials and / or emissive materials that include quantum dots or equivalent structures. Such emissive layers can include only quantum dot materials that convert light emitted by a separate emissive material or other emitter, or they can also include the separate emissive material or other emitter, or they can themselves directly emit light by application of an electric current. Similarly, color conversion layers, color filters, up-conversion or down-conversion layers or structures can include materials that include quantum dots, but such layers can not be considered "emissive layers" as disclosed herein. In general, an "emissive layer" or material is one that emits primary light that can be altered by another layer within the device that does not itself emit primary light, such as a color filter or other color conversion layer, and that can also re-emit altered light with different spectral content based on the primary light emitted by the emissive layer.

[0047] Unless otherwise described, any of the layers of the various embodiments can be deposited by any suitable method. For organic layers, preferred methods include thermal evaporation, ink-jet (as described in U.S. Pat. Nos. 6,013,982 and 6,087,196, both of which are incorporated by reference in their entireties), organic vapor phase deposition (OVPD) as described in U.S. Pat. No. 6,337,102, which is incorporated by reference in its entirety, and deposition by organic vapor jet printing (OVJP), as described in U.S. Pat. No. 7,431,968, which is incorporated by reference in its entirety. Other suitable deposition methods include spin coating and other solution based processes. Solution based processes are preferably conducted in nitrogen or inert atmospheres. For other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding (e.g. as described in U.S. Pat. Nos. 6,294,398 and 6,468,819, both of which are incorporated by reference in their entireties) and patterning associated with some of the deposition methods such as ink-jet and OVJD. Other methods can also be used. The materials to be deposited can be modified in order to enhance their suitability for a particular deposition method. For example, substituents can be used in small molecules to enhance their solution-processability, for example alkyl and aryl groups having 3 or more carbons are preferred, and alkyl groups of 20 carbons or more can be used, with 3 to 20 carbons being a preferred range. Materials with asymmetric structures can have better solution-processability than those with symmetric structures, because they can have lower re-crystallization tendency. Dendrimer substituents can be used in small molecules to enhance their solution-processability.

[0048] A device fabricated according to embodiments of the present application can further optionally include a barrier layer. One use of a barrier layer is to protect the electrodes and organic layers from damage by exposure to harmful substances in the environment, including moisture, vapor, and / or gases. The barrier layer can be deposited on the substrate, over the electrodes, under the electrodes, or beside the electrodes, or on any other portion of the device, including the edges. The barrier layer can include a single layer or multiple layers. The barrier layer can be formed by various known chemical vapor deposition techniques, and can include compositions having a single phase as well as compositions having multiple phases. Any suitable material or combination of materials can be used for the barrier layer. The barrier layer can incorporate inorganic compounds or organic compounds or both. Preferred barrier layers include mixtures of polymeric materials and non-polymeric materials, as described in U.S. Patent Nos. 7,968,146, PCT Patent Application Nos. PCT / US2007 / 023098 and PCT / US2009 / 042829, which are incorporated herein by reference in their entirety. To be considered a "mixture," the aforementioned polymeric and non-polymeric materials making up the barrier layer should be deposited under the same reaction conditions and / or simultaneously deposited. The weight ratio of polymeric material to non-polymeric material can range from 95:5 to 5:95. The polymeric and non-polymeric materials can be produced from the same precursor materials. In one example, the mixture of polymeric material and non-polymeric material consists essentially of polymeric silicon and inorganic silicon.

[0049] In some embodiments, at least one of the anode, the cathode, or a new layer disposed above the organic emissive layer acts as an enhancement layer. The enhancement layer includes a plasmonic material that exhibits surface plasmon resonance, which non-radiatively couples to the emitter material and transfers excitation state energy from the emitter material to non-radiative modes of the surface plasmon polaritons. The enhancement layer is provided no more than a threshold distance from the organic emissive layer, where the emitter material has 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 the distance at which the total non-radiative decay rate constant equals the total radiative decay rate constant. In some embodiments, the OLED further includes an out-coupling layer. In some embodiments, the out-coupling layer is disposed above the enhancement layer on the opposite side of the organic emissive layer. In some embodiments, the out-coupling layer is disposed on the side of the emissive layer opposite the enhancement layer, but still enables out-coupling of energy from the surface plasmon modes of the enhancement layer. The out-coupling layer scatters energy from the surface plasmon polaritons. In some embodiments, this energy is scattered in the form of photons to free space. In other embodiments, the energy is scattered from the surface plasmon modes to other modes of the device, such as but not limited to an organic waveguide mode, a substrate mode, or another waveguide mode. If the energy is scattered to a non-free space mode of the OLED, other out-coupling schemes can be incorporated to extract the energy to free space. In some embodiments, one or more intermediate layers can be disposed between the enhancement layer and the out-coupling layer. Examples of intermediate layers can be dielectric materials, including organic, inorganic, perovskite, oxide, and can include stacks and / or mixtures of these materials.

[0050] The enhancement layer modifies the effective properties of the medium in which the emitter material resides, resulting in any or all of the following: reduced emissivity, modified emission line shape, emission intensity and angular variation, stability variation of the emitter material, efficiency variation of the OLED, and reduced efficiency decay of the OLED device. Placing the enhancement layer on the cathode side, the anode side, or both, results in 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 described, the OLEDs according to the present disclosure can also include any of the other functional layers typically found in OLEDs.

[0051] The enhancement layer can be constructed from plasmonic materials, optically active metamaterials, or hyperbolic metamaterials. As used herein, a plasmonic material is a material whose real part of the permittivity crosses zero in the visible or ultraviolet region of the electromagnetic spectrum. In some embodiments, the plasmonic material includes at least one metal. In such embodiments, the metal can 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, a metamaterial is a medium constructed from different materials in which the medium as a whole behaves differently than the sum of its material constituents. In particular, we define an optically active metamaterial as a material that has both a negative permittivity and a negative permeability. On the other hand, a hyperbolic metamaterial is an anisotropic medium whose 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 ("DBRs"), in that the medium should exhibit a length scale for the wavelength of light in the direction of propagation that is uniform. Using terminology that will be understood by those skilled in the art: the permittivity of a metamaterial in the direction of propagation can be described using an effective medium approximation. Plasmonic materials and metamaterials provide a way to control light propagation that can enhance OLED performance in a variety of ways.

[0052] In some embodiments, the enhancement layer is provided as a planar layer. In other embodiments, the enhancement layer has periodically, quasi-periodically, or randomly arranged wavelength-sized features, or periodically, quasi-periodically, or randomly arranged subwavelength-sized features. In some embodiments, the wavelength-sized features and the subwavelength-sized features have sharp edges.

[0053] In some embodiments, the outcoupling layer has periodically, quasi-periodically or randomly arranged wavelength-sized features, or periodically, quasi-periodically or randomly arranged sub-wavelength-sized features. In some embodiments, the outcoupling layer can 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 can 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 additional layers disposed on the plurality of nanoparticles, changing the thickness of the enhancement layer, and / or changing the material of the enhancement layer. The plurality of nanoparticles of the device can be formed of at least one of: a metal, a dielectric material, a semiconductor material, a metal alloy, a mixture of dielectric materials, a stack or a hierarchy of one or more materials, and / or a core of one type of material 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 can have additional layers disposed thereon. In some embodiments, the polarization of the emission can be tuned using the outcoupling layer. Changing the dimensions and periodicity of the outcoupling layer can select a class of polarizations that preferentially outcouple to air. In some embodiments, the outcoupling layer also serves as an electrode of the device.

[0054] It is believed that the internal quantum efficiency (IQE) of fluorescent OLEDs can exceed the 25% spin-statistics limit by delayed fluorescence. As used herein, there are two types of delayed fluorescence, P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence results from triplet-triplet annihilation (TTA).

[0055] On the other hand, E-type delayed fluorescence does not rely on the collision of two triplets, but rather on the thermal population of triplet to singlet excited states. Compounds capable of producing E-type delayed fluorescence must have a very small singlet-triplet gap. Thermal energy can activate the triplet to transfer back to the singlet. This type of delayed fluorescence is also known as thermally activated delayed fluorescence (TADF). A unique feature of TADF is that the delayed component increases with increasing temperature due to the thermal energy. If the rate of reverse intersystem crossing is fast enough to minimize non-radiative decay from the triplet, the fraction of singlet excited states that are refilled can reach 75%. The total singlet fraction can be 100%, far exceeding the spin-statistics limit for electrically generated excitons.

[0056] E-type delayed fluorescence characteristics can be seen in exciplex systems or in single compounds. Without being bound by theory, it is believed that E-type delayed fluorescence requires that the light emitting material have a small singlet-triplet energy gap (ΔES-T). Organic non-metal containing donor-acceptor light emitting materials can be able to achieve this. Emission from these materials is often characterized by donor-acceptor charge transfer (CT) type emission. The spatial separation of the HOMO and LUMO in these donor-acceptor type compounds often results in a small ΔES-T. These states can involve CT states. Typically, donor-acceptor light emitting materials are constructed by linking an electron donor moiety (such as an amino or carbazole derivative) to an electron acceptor moiety (such as an N-containing six-membered aromatic ring).

[0057] Devices fabricated in accordance with embodiments of the disclosure can be incorporated into a wide variety of electronic apparatuses (or units) that can be incorporated into a wide variety of electronic products or intermediate components. Examples of such electronic products or intermediate components include display screens that can be utilized by end-user product manufacturers, lighting devices (such as discrete light source devices or lighting panels), and the like. The electronic apparatuses can optionally include driving electronics and / or power supplies. Devices fabricated in accordance with embodiments of the disclosure can be incorporated into a wide variety of consumer products that have one or more electronic apparatuses (or units) incorporated therein. A consumer product is disclosed that includes an OLED having an organic layer that includes a compound of the disclosure. Such consumer products should include any kind of product that includes one or more of a light source and / or some type of visual display. Some examples of such consumer products include flat panel displays, curved panel displays, computer monitors, medical monitors, televisions, billboards, interior or exterior lighting and / or signaling lights, heads-up displays, fully or partially transparent displays, flexible displays, rollable displays, foldable displays, stretchable displays, laser printers, telephones, cell phones, tablet computers, phablets, personal digital assistants (PDAs), wearable devices, notebook computers, digital cameras, camcorders, viewfinders, micro-displays with a diagonal less than 2 inches, 3D displays, virtual reality or augmented reality displays, vehicles, video walls comprising multiple displays tiled together, theater or stadium screens, and signs. Devices fabricated in accordance with the disclosure can be controlled using a variety of control mechanisms, including passive matrix and active matrix. Many of the devices are intended for use in temperature regimes comfortable to humans, such as 18 °C to 30 °C, and more preferably at room temperature (20-25 °C), but can be used outside this temperature regime (e.g., -40 °C to 80 °C).

[0058] The materials and structures described herein can be applied in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors can employ the described materials and structures. More generally, organic devices such as organic transistors can employ the described materials and structures.

[0059] In some embodiments, the OLED has one or more features selected from the group consisting of: flexible, rollable, foldable, stretchable, and bendable. In some embodiments, the OLED is transparent or semi-transparent. In some embodiments, the OLED further comprises a layer comprising carbon nanotubes.

[0060] In some embodiments, the OLED further comprises a layer comprising a delayed fluorescence emitter. In some embodiments, the OLED comprises 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 with a diagonal less than 10 inches or an area less than 50 square inches. In some embodiments, the OLED is a display panel with 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.

[0061] In some embodiments of the emissive region, the emissive region further comprises a host.

[0062] In some embodiments, the compound can be an emissive dopant. In some embodiments, the compound can generate emission via phosphorescence, fluorescence, thermally activated delayed fluorescence (i.e., TADF, also known as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes.

[0063] The OLEDs disclosed herein can be incorporated into one or more of consumer products, electronic component modules, and illumination panels. The organic layer can be an emissive layer and the compound can be an emissive dopant in some embodiments, while the compound can be a non-emissive dopant in other embodiments.

[0064] The organic layer can also contain a host. In some embodiments, two or more hosts are preferred. In some embodiments, the host used can be a) ambipolar, b) electron transporting, c) hole transporting, or d) wide band gap material that plays little role in charge transport. In some embodiments, the host can contain a metal complex. The host can be an inorganic compound.

[0065] Combinations with other materials

[0066] Materials described herein as useful for particular layers in an organic light emitting device can be used in combination with a variety of other materials present in devices. For example, light emitting dopants disclosed herein can be used in conjunction with a variety of hosts, transport layers, blocking layers, injection layers, electrodes and other layers that can be present. The materials described or referenced below are non-limiting examples from among the many that can be used in combination with the compounds disclosed herein, and one of skill will readily recognize from the literature that many other materials can be used in combination.

[0067] Different materials can be used for different emissive layers and non-emissive layers and arrangements disclosed herein. Examples of suitable materials are disclosed in U.S. Patent Application Publication No. 2017 / 0229663, incorporated by reference in its entirety.

[0068] Conductivity dopants:

[0069] Charge transport layers can be doped with conductivity dopants to substantially alter their charge carrier density, which in turn will alter their conductivity. The conductivity is increased by the creation of charge carriers in the host material, and depending on the type of dopants, a shift in the Fermi level of a semiconductor can also be achieved. Hole transport layers can be doped with a p-type conductivity dopant, and n-type conductivity dopants are used in electron transport layers.

[0070] HIL / HTL:

[0071] The hole injection / transport material used in the present application is not particularly limited, and any compound can be used as long as the compound is generally used as a hole injection / transport material.

[0072] EBL:

[0073] An electron blocking layer (EBL) can be used to reduce the number of electrons and / or excitons that leave an emissive layer. The presence of the blocking layer in a device can result in a device with greater efficiency and / or longer lifetime as compared to a similar device lacking the blocking layer. Additionally, the blocking layer can be used to confine 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 a higher triplet energy than the emitter closest to the EBL interface. In some embodiments, the EBL material has a higher LUMO (closer to the vacuum level) and / or a higher triplet energy than one or more of the hosts closest to the EBL interface. In one aspect, the compounds used in the EBL contain the same molecule or the same functional group as used in one of the hosts described below.

[0074] Hosts:

[0075] The light-emitting layer of the organic EL device of the present application preferably contains at least a metal complex as a light-emitting material, and can contain a host material using a metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complex or organic compound can be used as long as the triplet energy of the host is greater than that of the dopant. Any host material can be used with any dopant as long as the triplet criterion is satisfied.

[0076] HBL:

[0077] A hole blocking layer (HBL) can be used to reduce the number of holes and / or excitons leaving the light-emitting layer. The presence of such a blocking layer in a device can result in a generally higher efficiency and / or a longer lifetime compared to a similar device lacking the blocking layer. In addition, the blocking layer can serve to confine the emission to a desired region of the OLED. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and or a higher triplet energy than the emitter closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (further from the vacuum level) and or a higher triplet energy than one or more of the hosts closest to the HBL interface.

[0078] ETL:

[0079] An electron transport layer (ETL) can comprise a material capable of transporting electrons. The electron transport layer can be intrinsic (undoped) or doped. Doping can be used to enhance the conductivity. Examples of ETL materials are not particularly limited and can be any metal complex or organic compound, as long as it is typically used to transport electrons.

[0080] Charge generation layer (CGL)

[0081] In a tandem or stacked OLED, the CGL plays an essential role in performance, which consists of an n-doped layer and a p-doped layer for injecting electrons and holes, respectively. Electrons and holes are supplied by the CGL and electrodes. The consumed electrons and holes in the CGL are refilled by electrons and holes injected from the cathode and anode, respectively; subsequently, the ambipolar current gradually reaches a steady state. Typical CGL materials include n- and p-conductivity dopants used in the transport layers.

[0082] As previously disclosed, conventional OVJP processes generally involve dispensing organic materials, such as active organic AMOLED materials, in a heated gaseous mixture through a print nozzle. Conventional OVJP processes generally use a pressure range between 10 Torr and 1 Atm (760 Torr). Print nozzles can be fabricated using microelectromechanical (MEMS), micromachining, 3D printing, or similar processes. Example structures of OVJP depositor devices are provided herein, but a general "print bar" as disclosed herein can include one or more "print heads," each of which includes at least one print die. Print heads generally include an interface to each print die in the print head, including a mechanical mount, a gas delivery system, a venting interface, a heating component, etc. Using multiple print heads on a print bar can enable, for example, simultaneous printing of multiple pixels on a substrate. The print bar itself can be heated in order to facilitate the deposition process.

[0083] Embodiments disclosed herein provide various systems and techniques that allow for efficient transport of a substrate past one or more print bars in a deposition chamber, while allowing for precise and efficient control of the proximity between the substrate and the print bars. This in turn can allow for precise control of the thickness and uniformity of layers printed with the system, which can vary depending on the application. For example, different sizes and types of display panels can require different thicknesses, tolerances, etc. The print bars and substrate can also be moved relative to each other, for example to allow the print bars to be arranged perpendicular or parallel to the substrate, or at any other desired angle relative to the substrate or system (e.g. relative to the primary y-axis). The substrate can also be rotated or translated in other directions during processing, i.e. while the substrate is moved in the primary y-direction through the system. For example, when printing sub-pixels or similar features, material can be printed along the y-axis, and after printing a sub-pixel or set of sub-pixels, the substrate can be moved in another direction, for example by shifting one sub-pixel position along the x-direction. This process can be used, for example, to print multi-component or multi-color sub-pixels. As shown and described in various example arrangements herein, the print bars are generally arranged perpendicular to the direction of substrate motion during processing, while the substrate and / or substrate carrier (e.g. a flat table) can be rotated relative to the print bars. Individual or excess print bars or sets of print bars can be used.

[0084] The embodiments disclosed herein provide such arrangements in which the material to be printed via OVJP on the substrate has little or no direct physical contact between the substrate and any other surface, or in some embodiments only temporary or transient physical contact. This reduces the chance of undesirable voltage build-up and / or electrostatic discharge (ESD), thereby minimizing or eliminating associated damage to the substrate, pre-deposited layers, and underlying circuitry (e.g., display backplane or AMOLED layers). In most of the deposition systems disclosed herein, the substrate is not in physical contact with any surface. However, in some embodiments, the substrate can be contacted by a solid moving vacuum chuck on the back (non-acting) side of the substrate. When such a device is used, it can incorporate ESD minimizing technology such as ionizers and appropriate ESD safety technology to evacuate and remove the substrate from the chuck.

[0085] The embodiments disclosed herein are capable of depositing on a range of substrate types and sizes. For example, glass and other materials known for use in OLEDs can be used as the substrate on which material is printed by the systems disclosed herein. Conventional OLED manufacturing systems and similar systems can have difficulty handling and printing on certain substrates, such as very large glass substrates, due to the increased momentum caused by moving the substrate in the system and possible sagging of unsupported portions of the substrate. However, it is generally undesirable to physically support the substrate at all points due to the risk of damage or contamination to the substrate. To address these issues, the embodiments disclosed herein use various combinations of pressure vacuum float tables and other components as described in further detail below. These embodiments allow for handling of relatively large and sensitive substrates with greatly reduced risk of damage and contamination. The embodiments disclosed herein can efficiently handle and deposit material on substrates with edge measurements of 1-5 m or more. As disclosed herein, larger substrates, referred to as "mother glass," can also be used to manufacture multiple devices in a single pass or few passes through the deposition system, after which the larger substrate is divided into individual devices. For example, current 10th or 11th generation mother glass typically has dimensions of about 2940 mm x 3370 mm, and substrates of this size can be successfully handled and processed by the embodiments disclosed herein. More generally, substrates with a maximum edge measurement of 1 m, 2 m, 3 m, 4 m, or 5 m in any aspect ratio can be handled and processed by any of the embodiments disclosed herein.

[0086] The systems as disclosed herein can accept an input substrate, i.e., a substrate on which material is to be deposited via OVJP, via a pressure-regulated load lock chamber. After material has been deposited on the substrate, the substrate can be output to the same input lock or a separate output load lock, in order to enable integration into various manufacturing systems and technologies. For example, the deposition systems disclosed herein can be used in in-line manufacturing systems and processes, in which the substrate is moved in one direction throughout the manufacturing process.

[0087] The embodiments disclosed herein can include a plurality of print bars, each of which can include one or more print dies, and / or smaller print bars, each of which can include one or more print dies. Each print die can be enclosed in a "print engine" as disclosed herein. As used herein, a "print engine" is a component or subsystem that provides an integrated and consistent framework for gas input, gas exhaust, height measurement, and active height control for an associated print die. Generally, a print bar as disclosed herein includes one or more print engines.

[0088] The use of multiple print bars can allow the system to become flexible, e.g., to be able to distribute multiple chemicals within a single processing chamber, to reduce the time for the system to load and unload relative to conventional systems, to improve the uniformity of printing, etc. The use of multiple and / or smaller print bars also allows for greater flexibility. In some configurations, each smaller print bar can be controlled to move perpendicular to the motion of the substrate through the system, to move parallel to the substrate motion, and / or to move in the vertical (z) direction relative to the substrate, i.e., closer or further from the substrate surface on which material is deposited.

[0089] The print bars as disclosed herein can span the width of the system, such that the print bars extend across the width of a substrate processed by the system, thereby allowing for deposition on any portion of the substrate. In the case of multiple print bars, the print bars can be arranged in an in-line or staggered arrangement.

[0090] Embodiments disclosed herein allow for range and various physical motion control of the substrate and / or other components of the system to allow for precise positioning of the substrate relative to the OVJP print nozzles. For example, as the substrate moves past one or more print bars, active positioning adjustments can be used to control the positioning of the substrate in the plane of the substrate and vertically towards or away from the print bars. Generally, it is preferred to maintain the surface of the substrate in a plane that is parallel or substantially parallel to the plane of the OVJP nozzles in the print bars, preferably within a range of 1-10 degrees or less, preferably less than 5 degrees, more preferably less than 1 degree. More generally, embodiments disclosed herein include physical controls that allow for precise adjustment of the gap between the print bars and the substrate to any close target separation value, which allows the system to maintain the substrate within the processing window of deposition. Similarly, some or all of the motion axes of the system can be synchronized, e.g., using a real-time controller, to allow for precise and regular adjustments of the print bars and substrate. In some embodiments, the substrate can also be rotated while inside the deposition system to allow for different orientations of the components relative to the deposited material in order to support different display and / or backplane orientations on the substrate. The various controllable motions of the system also allow for the substrate to pass multiple times through one or more print bars, e.g., to allow for simultaneous printing by multiple print bars, repeated sequential printing according to one or more print bars, patterned printing via one or more print bars, etc.

[0091] Embodiments can include a subsystem for inspection and / or calibration that can be moved through the deposition system along the direction of motion of the substrate past the print bars. This component can allow for periodic inspection and metrology of the print bars and nozzles in situ. For example, the system can have on-board optical, thermal, and other sensors that are also capable of moving in a direction parallel to the print bars so that any location of any print bar can be inspected. Data collected from print bar inspection, for example, can be used to make dynamic adjustments to the print bar or substrate motion, or to perform cleaning as needed. Data can also be used to predict possible failures and allow for predictable system maintenance.

[0092] Embodiments can include various components and techniques to manage the heat generated by the hot gaseous mixture ejected from the OVJP print nozzles and other components.

[0093] As with conventional OLED deposition systems (and other types of OVJP systems), the OVJP deposition systems as disclosed herein can be arranged within a vacuum chamber. In embodiments disclosed herein, the motion system can be isolated from the vacuum chamber walls, e.g., via an isolation mechanism that operates at the conventional atmospheric pressure (outside the chamber) through strategically placed guide holes as disclosed herein.

[0094] As previously disclosed, the OVJP print die as disclosed herein can be enclosed in one or more print bars by a print engine. As used herein, a print engine refers to a subsystem that includes one or more print dies, associated interfaces to input and exhaust air flows, height sensors (if present), and height adjustment mechanisms (if present). Figures 3A-3D An example of a print engine as disclosed herein is shown. Figure 3A Individual print engines are shown. Figure 3A The example in FIG. 1 is oriented in the upward direction, i.e. the nozzles face “up” (toward the top of the page). It should be understood that the same arrangement and configuration can be used for a downward-facing print head in embodiments where the substrate is positioned below the print head, i.e. in embodiments where the substrate is positioned relative to the print head in the direction of gravity. However, as used herein, a substrate can be described as being disposed “below” a print bar and a print bar as being located “above” a substrate when the substrate and print bar are arranged such that material ejected from the OVJP nozzles of the print bar is ejected toward the substrate, regardless of the arrangement of the components relative to the direction of gravity.

[0095] Figure 3B An example of a system using a print bar with multiple print engines operating at the print head level is shown, i.e. each print head includes a height sensor and vertical position control. Figure 3C A similar arrangement with a single print engine operating at the print bar level is shown, i.e. the print bar includes multiple print heads but with a single vertical position control for the entire print bar. In Figure 3B In FIG. 1, each print head includes an individual height sensor, while in Figure 3C The print bar in FIG. 1 includes one or more height sensors and height adjusters that control the height of the entire bar. As previously disclosed, a print engine can include a print die 307 incorporated into a print head subassembly 310 as known in the OVJP art, which can include one or more heating elements 305, OVJP delivery nozzles, and other standard OVJP depositor components. In Figure 3DAn exploded view of the die manifold, heat shield, and other related components is shown. Whether using individual height adjusters or height adjusters at the print bar level, the print engine can include a height control (z-direction) mechanism 315, such as a control rod attached to an actuator, that can be used to adjust the height and / or orientation of the print head. In embodiments where each print head has individual height sensors and adjusters, height sensors 320 can be arranged to sit on the outer edge of the support structure 323 or otherwise arranged to detect and allow adjustment of the relative height of the print head with respect to the substrate. The entire assembly can also be supported by a lower support structure 321. A mixing chamber 322 can allow for mixing of one or more materials received from source chambers 325. The print die can also be in fluid communication with a venting channel 327, such as to allow for removal of gas and other materials in the region between the print head nozzles and the substrate during operation of the deposition system, and to limit lateral spreading of the material exiting each nozzle, so as to limit or prevent cross-talk between adjacent nozzles. As Figure 3B and 3C The print bar 301 can include a plurality of print heads 300, as shown. The interface of the print engine with gas input and venting is achieved through the use of a distribution manifold. A single manifold can serve multiple print engines or just a single engine. Notably, the use of a print engine as shown Figures 3A-3D is not relevant to the arrangements and configurations described herein with respect to substrate motion. That is, Figures 3A-3D The print bar and print head configuration shown can be used with any of the embodiments disclosed herein with appropriate changes, such as orienting the print bar to print in an upward or downward direction depending on the orientation of the substrate. In some embodiments, the print engine can include design features to manage the heat load from the thermal print die, such as the heat shield arrangement shown, which can be integrated closely with the print head to completely isolate the surrounding environment from the hot print head during operation. Figure 3D

[0096] The embodiments disclosed herein can use one or more print bars, each of which can include one or more print heads. As previously disclosed, in embodiments using multiple print bars, the print bars can be positioned in a linear arrangement, such as shown, or the print bars can be staggered with respect to one another, such as shown. Figure 3E Figure 3F ​​As shown, each of the figures illustrates a view of a representative print bar 350, 360 as seen from the perspective of a substrate in the OVJP system, each print bar comprising three print heads 351, 352, 353 and 365, 366, 367, respectively. For example, the print dies may have exclusion regions at the ends of each die that cannot be used for printing holes; these exclusion regions are used to process the die and attach it to the print engine. If these adjacent dies are close together, there may be fewer holes; in this case, considering these regions, a staggered arrangement may be preferred. Generally, both staggered and linear arrangements can be used to print selected areas, such as display planes or areas, in one or more passes. However, staggered arrangements are generally simpler and more efficient to assemble into the print bar compared to linear arrangements without end exclusion regions. The staggered arrangement also allows material to be deposited over relatively large areas, enabling the fabrication of 55" or larger display panels using the panel substrate through fewer passes of the system by using redundant parallel bars deposited over the same area of ​​the substrate. This allows for thicker substrate deposition with fewer scans below the printhead. When using, for example... Figure 3F In the case of an interleaved arrangement, the print heads on adjacent ends of the print rods can overlap with the print heads on another rod, for example... Figure 3F The printheads in the middle are 353 and 365.

[0097] Figure 4A and 4B Top-down and side views of an example OVJP deposition system according to embodiments disclosed herein are shown, respectively. A pressure vacuum (PV) floating stage 405, which may also be referred to herein and in the art as a “PV stage” or “floating stage,” supports a glass substrate on the non-active back side of the substrate. The floating stage, for example, uses nitrogen or other suitable gas to provide a vacuum / gas chamber and may be contained on one or more sides of the PV stage—preferably on all four sides of the PV stage—around one or more positioned holders 420. Because the substrate does not physically contact anything other than the substrate holders having minimal contact area in this and other embodiments, the probability of triboelectric charge accumulation is extremely low. The entire PV stage 405 can move as a single component or subsystem, wherein the substrate moves along the main y-direction of movement 401 from the input side (e.g., Figure 4Athrough the system and past the print bars 412 to complete printing. As previously disclosed, each print bar can include one or more print heads. For example, the system can include three print bars, each configured to print a primary color to produce a full color display on the substrate, although embodiments disclosed herein are not limited to any particular number of print bars or any particular arrangement of colors, chemicals, and / or other arrangements of materials. In this example, the active side of the substrate is facing up and the print bars are disposed above the substrate, printing down on the active side of the substrate. That is, the print bars are configured and arranged such that the material ejected from the print heads travels in the direction of gravity downward until it impacts the substrate surface facing the print bars.

[0098] Figure 4C A top view, side view, and front view of a substrate PV stage 405, which can itself be held on a PV stage support pedestal 402, is shown. The PV stage 405 can include features that maintain the system at a height and stable arrangement, such as mounting features that allow for precise leveling, latches, or other connectors to secure the stage to the support pedestal 402, etc. The stage 405 can include multiple pairs of vacuum chucks or sub-systems 420p, 420n, such as for longitudinal or transverse printing substrate arrangements, respectively, that hold the substrate. In particular, the substrate chucks 420 can allow for adjustment of the substrate position in at least two and preferably three angles of motion. For example, the substrate chucks can allow for movement of the substrate in the x, z, and / or theta directions. As used herein, the "x" direction refers to an axis in the plane of the substrate and perpendicular to the main y direction of movement 401 of the substrate through the deposition system; the "z" direction refers to a vertical direction, perpendicular to the plane of the substrate, toward / away from the print bars; and the "theta" refers to an angular / rotational adjustment of the substrate about the z axis, i.e., rotation in the plane of the substrate. Such motion can be implemented in any of the embodiments disclosed herein that use such chucks and / or allow for movement of the substrate and / or any substrate support structure, such as the substrate float stage 405 shown. This adjustability allows for alignment of the backplane on the substrate with the print bars and provides a mechanism to maintain precise alignment even as the substrate travels through the system.

[0099] The deposition system can also include one or more controls provided for user and / or automated control of the substrate holder. For example, the controls can include human interface components and / or electronic interfaces that allow adjustment of each angle of motion available to the holder. The holder 420 can include minimal physical contact means to hold and position the substrate, such as vacuum or other pressure-based holders that hold only one or more edges and / or only the backside of the substrate. Thus, the holder controls can include pressure-volume (PV) controls. The substrate holder as disclosed herein can also be used to maintain the substrate in a planar arrangement, for example by counteracting the force of gravity that would otherwise cause the substrate to sag. As a particular example, one or more substrate holders can hold the edges and / or inactive backside of the substrate to maintain it in a planar configuration while it is being processed by the system. This feature can be particularly desirable in embodiments in which the printbar prints in an upward direction, i.e., in a direction opposite to the force of gravity.

[0100] The substrate PV stage 405 can include one or more lift pins 427, which can be used to initially position the substrate 110 on the PV stage prior to retraction to allow the substrate 110 to be suspended and held in place by the air cushion provided by the PV stage. Lift pins or equivalent components can be used, for example to position the substrate using minimal surface area contact with the substrate. Alternatively, the lift pins can include channels to allow pressurized gas to pass through the pins, thereby causing the substrate to float on the lift pins. In some embodiments disclosed herein that use a PV float stage or equivalent structure, the substrate can be moved on the PV stage independently of movement of the PV stage itself. That is, the float stage can be moved through the system, for example from an input lock to an output lock along a path that moves the PV stage and substrate under the printbar. At the same time, the position of the substrate on the PV stage can be adjusted as disclosed herein, regardless of the position and / or movement of the PV stage. This arrangement can allow the use of a PV stage to make relatively large movements of the substrate, while fine-tuning of the substrate relative to, for example, the printbar can be made on the PV stage and independently of the motion of the PV stage (for example, using a substrate holder as previously disclosed). Alternatively, the substrate can be held in a fixed position relative to the PV stage by a holder as the substrate is moved on the PV stage through the deposition system. In some embodiments, movement and positioning of the substrate holder can be at least partially controlled by the PV float stage or synchronized with movement of the stage. For example, after the substrate is floated on the PV stage in the z-direction, the substrate holder can be operated in a weightless state, for example via holder controls as disclosed herein.

[0101] The floating stage may include a gas confinement system to prevent gas ejected from the OVJP printing bar from leaking to the edge of the substrate. For example, gas curtains and / or exhaust channels may be positioned around the edge of the substrate via channels in the floating stage to exhaust any overflowing gas from the substrate and the floating stage.

[0102] In some embodiments, the printing rod may also be immersed in the PV stage, for example... Figure 4E As shown in diagram 406, it can be controlled simultaneously or individually relative to the substrate PV stage 405. The printing bar PV stage can be used as... Figure 4E The bearings shown, similar to the operation of the substrate PV stage and / or holder as disclosed herein, are further used to planarize the substrate. In some embodiments, the movement of the substrate PV stage and print bar assembly (whether or not it is immersed in the PV stage) is coordinated to achieve a specific relative physical arrangement as previously disclosed. The position of the print bars and / or the position of individual print engines on each print bar can be adjusted relative to the physical frame holding the print bars and / or relative to the substrate being processed by the system. For example, the height of the print bars above the substrate can be adjusted. In the case of using multiple print bars, the height of the print bars can be adjusted simultaneously or individually, such that the height of each print bar can be adjusted without affecting the height of the other print bars. The print bar 412 and / or PV stage 405 can also rotate in a plane parallel to the substrate, for example to allow printing in “portrait printing” or “landscape printing” modes without rotating the substrate.

[0103] The in-situ printhead alignment, measurement, and inspection subsystem 409 can be used as previously disclosed, which... Figure 4A The configuration is shown as "parked". During operation, subsystem 409 can move along the main y-direction 401, similar to substrate PV stage 405.

[0104] As previously disclosed, one or more alignment sensors, such as vision cameras, IR cameras, barcode readers, or similar sensors 415, can be used to align the substrate disposed on the PV stage 405 with the print bar 412. For example, the PV stage 405 or the substrate itself may contain various physical or electronic markers that can be positioned relative to the print bar 412 or the print bar support stage 406 in a known arrangement. The alignment sensor 415 may be mounted on a common physical frame with the print bar 412, for example, to ensure that the alignment sensor 415 takes into account any movement of the print bar 412. Alternatively, the sensor 415 may be separate from the printing subsystem and may be located outside the deposition chamber. For example, some types of alignment sensors may be incompatible with the high vacuum environment in the deposition chamber. Regardless of the positioning, the sensor 415 can provide a signal that allows adjustment of the relative position of the substrate and the print bar to maintain proper alignment as previously disclosed. As another example, the alignment sensor may be vacuum-compatible, but may be located outside the deposition chamber for other reasons, such as ease of user access, installation preferences, etc.

[0105] Figure 4D It shows the arrangement in the vacuum chamber Figures 4A-4C A front view of the OVJP system. The vacuum chamber 450 can be configured such that each part is sealed relative to the others to maintain a low-pressure internal environment. For example, the cap 451 can be sealed relative to the body via an O-ring 452 or a similar mechanism. An OVJP system support column 470 can pass through the vacuum chamber 450, wherein the associated opening in the vacuum chamber base is sealed by a pass-through sealed bellow 472. An external isolator 477 physically isolates the OVJP system 499 from the surrounding environment and / or vibrations and other movement of the vacuum chamber itself. More generally, these features allow the deposition system 499—which can be… Figures 4A-4C The system shown, or any other embodiment disclosed herein, is isolated from the base and walls of the vacuum chamber 450 so that movement of the chamber will not affect the deposition system's handling of the apparatus.

[0106] In some embodiments, the relative bearing can be used to flatten variations in substrate thickness, for example... Figure 4E As shown. Compared to other embodiments disclosed herein, the substrate does not experience significant movement or acceleration because the total motion can be performed by moving the substrate PV stage 405. The gripper 420, arranged parallel to the direction of movement of the substrate PV stage 405, can be used for fine adjustments to correct for repeatable motion errors of the moving PV stage 405.

[0107] As with other embodiments disclosed herein, the substrate can be rotated 90 degrees into and out of "portrait printing" and "landscape printing" modes or any other desired orientation, e.g., using a substrate gripper, depending on the alignment of the longer side of the substrate relative to the printbar. Alternatively, the entire stage can be rotated between orientations. This can be preferred in some arrangements because the incomplete coverage of the PV stage can affect the floating properties of the substrate.

[0108] In some embodiments, the substrate PV stage 405 can also be used to cool the substrate, e.g., via passive and / or active cooling techniques. As previously disclosed, this rotation can be performed independently of any other motion or positioning of the PV float stage. For example, a gripper used to position the substrate on the PV stage can rotate the substrate to any desired position without regard to the position of the stage and / or while the stage is moving along the major y-axis of the system.

[0109] Figures 4A-4E The illustrated embodiment and other embodiments disclosed herein can also allow for reduced consumption of float stage gas because there is no infeed or outfeed air table. For example, compared to other embodiments disclosed herein, the substrate can be covering the float stage at all times during the printing process, thereby minimizing the consumption of float stage gas (e.g., nitrogen) during operation. In other embodiments using an infeed and / or outfeed float stage architecture, the substrate is typically moved on top of and along the infeed and outfeed stages. Thus, the stages are partially covered by glass in transit and can therefore require higher gas consumption. An example of such an arrangement is shown in Figure 6 which uses a longer, fixed float stage with infeed / outfeed zones instead of a float stage on a moving carrier. Figures 4A-4E The embodiment in also has a relatively wet moving portion above the substrate, which further reduces the chance of particle contamination during the printing process.

[0110] Figure 5A and 5B show side and front views, respectively, of a similar arrangement in which the substrate and printbar are flipped vertically compared to the embodiment of Figures 4A-4E . That is, the system uses the same PV chuck concept as described with respect to Figures 4A-4E to hold the substrate while moving. However, the substrate enters the system with the active side down, and the printbar is disposed below the substrate with respect to the direction of gravity, but for clarity of the process description, the substrate is still generally described as disposed "below" the printbar because the material is still ejected from the OVJP print head toward the substrate, opposite the direction of gravity. The gantry is above the substrate. The PV chuck holding the substrate can be used to manage the risk of unintentional downward motion of the substrate toward the printbar. A similar PV system can be used in other embodiments disclosed herein, e.g.,Figure 8 the embodiments shown, or more generally any embodiment where it is desirable to position the substrate above the OVJP printbar with respect to the direction of gravity.

[0111] Figures 6-9 Alternative embodiments are shown that incorporate some or all of the features previously described with respect to Figures 4A-4E and 5A-5B.

[0112] Figure 6 A top, front, and side view of an embodiment is shown in which the substrate 110 enters the system from the loadlock in a face down manner with the active side (i.e. the side on which the organic and other OLED layers are deposited and will emit light after fabrication) facing down, as in Figures 5A-5B the arrangement in. In this embodiment, the substrate moves on a PV table that extends through the system, as compared to the smaller PV table in Figures 4A-4E and 5A-5B that moves with the substrate through the system. As previously disclosed, the area of the PV table where material is printed on the substrate precisely controls the separation between the printbar and the substrate. Similar to the arrangement in Figures 4A-4E and 5A-5B, the substrate is supported on a lift pin air cushion for alignment so as not to be in physical contact with any other surface, thereby reducing or eliminating friction ESD voltage buildup. In this arrangement, the lift pin can contact the back (non-active) side of the substrate. By contrast, in the arrangement in Figures 5A-5B , the lift pin will contact the active side of the substrate during loading or unloading, which is undesirable. The use of a lift pin with an air cushion allows the substrate to float on an air chamber provided by the air cushion during loading, unloading, or alignment of the substrate in the system. The substrate can be held and moved by one or more clamps as previously disclosed that contact the substrate on the non-active back side. The substrate moves on the PV air table from a feed zone, through the area under the printbar, and to a feed-out zone on the air table, with the active side always referenced to the air table. Automatic or semi-automatic alignment as previously disclosed, for example via the use of cameras or other aligners, can be used to more precisely position the substrate.

[0113] The printbar is positioned below the plane of the substrate, printing upward toward the active side of the substrate, and across a direction perpendicular to the primary motion of the substrate. The printbar can be immersed in a dedicated PV air table in such a way that the active side of the substrate is directly referenced to the PV air table of the printbar. This allows precise control of the vertical fly height gap between the substrate and the underlying printbar independent of variations in substrate thickness. The relatively light weight of the substrate and moving clamps allows accurate dynamic control of the motion of the substrate during the printing process. Similar printbar PV table arrangements can be used in any of the other embodiments disclosed herein to allow further control of the vertical distance between the substrate and the printbar.

[0114] Figure 7 An arrangement similar to that of Figure 6 is shown, but with the substrate entering the system with the active side facing up from the load lock. In addition to the relative positioning of the substrate and print bar, Figure 7 The arrangement of Figure 6 is the same or substantially the same as that of The substrate is supported on a lift pin air cushion for alignment so that the substrate is not in physical contact with any other surface and can be held and moved by one or more clamps that contact the substrate on the non-active backside. The substrate is moved from the infeed zone on the air table, through the area beneath the print bar, and into the outfeed zone on the air table. The print bar is positioned above the plane of the substrate, printing down toward the active side of the substrate, and across the direction perpendicular to the primary motion of the substrate. As previously disclosed, the print bar can also be immersed in a dedicated PV air table that can be configured to precisely control the vertical fly height gap between the substrate and the overhanging print bar. The relatively light weight of the substrate and moving clamps allows for accurate dynamic control of the motion of the substrate during the printing process.

[0115] Figure 8 An arrangement is shown in which the substrate enters the system with the active side facing down, consistent with that shown in Figure 6 In this arrangement, the non-active backside of the substrate is held by a top PV table, while the active front side of the substrate is supported by a lower PV table, as shown in Figure 6 As previously disclosed, the substrate can be supported on a lift pin air cushion for alignment to reduce or eliminate ESD voltage build-up from friction. The air table is referenced to the non-active backside of the substrate in the infeed and outfeed zones. The print bar is positioned beneath the substrate in the print zone relative to the direction of gravity, and holds the substrate from the top as the substrate moves past the print bar. This embodiment can therefore benefit from tighter motion and PV control to prevent gravity from causing portions of the substrate to sag or move the entire substrate. The print bar prints up toward the active side of the substrate, and across the direction perpendicular to the primary motion of the substrate. As with the arrangement shown in Figure 6 the print bar itself can be located in a dedicated PV air table to allow more precise control of the vertical fly height gap between the substrate and the underlying print bar, independent of variations in substrate thickness. The relatively light weight of the substrate and moving clamps allows for accurate dynamic control of the motion of the substrate during the printing process.

[0116] Figure 9 A front view is shown of an alternative arrangement, in which the substrate enters the system with the active side facing down, consistent with that shown in Figure 6 and 7The illustrated arrangement compares to a substrate not supported on an air table as it enters the system. Instead, the substrate is vacuum-chucked onto a large and very flat chuck surface with the active side down. The printbar is disposed below the substrate with respect to gravity and prints up onto the active surface of the substrate. The moving substrate payload must be much Figure 6 and Figure 7 heavier, and this heavy mass moves through the system. Thus, in this arrangement, careful consideration of correction for dynamic motion errors can be required.

[0117] Embodiments disclosed herein allow the substrate to exit the system after material has been deposited by the OVJP printbar in one of two ways: via the input loadlock by which the substrate initially entered the deposition system, or; by means of a dedicated output loadlock, allowing for "in-line" forward distribution of the substrate, for example, in a dedicated fab environment. In-line arrangements can use dedicated features of the vacuum chamber and contemplated system transport to enable in-line motion. For example, with reference to the arrangement illustrated in Figure 6 and similar arrangements, a dual gripper selection can be used, where a first dedicated gripper transports the substrate past the printbar and onto the exit air table, while a second, separate gripper now transports the substrate to the exit loadlock, while the primary gripper quickly returns to the input air table to accept a new substrate from the input loadlock. Similar mechanisms can be used for any other system transport arrangement disclosed herein, including any of those described with respect to Figures 4A-4E , 5A-5B, and 6-9.

[0118] Embodiments disclosed herein can operate at a range of internal pressures. While the deposition chamber can be referred to as a "vacuum chamber", during deposition by the OVJP deposition system, the operating pressure within the chamber can be as high as 100-300 Torr, or in some embodiments, as high as 400 Torr, which is a much higher pressure than conventional "vacuum" operating pressures, but is sufficient to float the substrate on a float table as disclosed herein.

[0119] Unless explicitly indicated otherwise or not possible or practical due to physical constraints, any feature disclosed herein with respect to one or more embodiments can be used with any other embodiment disclosed and / or claimed herein. As a non-limiting example, any embodiment using a substrate gripper as disclosed herein can include edge and / or backside substrate grippers in any configuration and arrangement disclosed or illustrated with respect to any of the embodiments disclosed herein. As another non-limiting example, any embodiment disclosed herein can allow for rotation of the substrate in the x-y plane during processing of the substrate in the deposition system.

[0120] In addition to the arrangements presented herein in which the substrate moves through the region beneath the printbar, in some embodiments the printbar can remain stationary relative to the deposition chamber while the printbar structure moves above the substrate. More generally, while described herein as movement of the substrate, equivalent movement can be achieved by moving the substrate and / or the printbar structure relative to one another. For example, a floating table and one or more clamps as previously disclosed can be used to hold the substrate in the deposition system while still minimizing physical contact with the substrate. One or more print engines, printbars, printheads, or any suitable combination thereof can then move across the region above the substrate while material is ejected from the printheads to be deposited on the substrate.

[0121] While disclosed and illustrated with respect to jet printing of organic materials for ease of illustration, embodiments disclosed herein can be used to deposit other materials and / or variant deposition techniques. For example, non-organic materials, biological materials, or other materials that are compatible or substantially compatible with general process parameters known to be suitable for organic materials or variants thereof can be used.

[0122] As a particular example, any of the embodiments disclosed herein can be used to deposit lines of condensable material on a glass or similar substrate, such as architectural glass. Such lines can be used to absorb IR radiation, provide electrical lines for embedded electronic components, or otherwise create other properties of the glass as a whole. Such lines can be relatively thin, such as 25, 50, or 100 pm, meaning that they can be printed on the glass without significantly impacting the apparent transparency of the glass. As a particular example, where thin lines of IR-absorbing material are printed on glass, the resulting glass can be suitable for office buildings and similar locations where it is desirable to allow a large amount of visible light into the building while also blocking a large amount of infrared light. In comparison to conventional deposition systems, particularly jet-based systems, embodiments disclosed herein can be particularly suitable for such applications, which can be less suitable for manipulation and deposition on the relatively large substrates disclosed herein.

[0123] 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 can be substituted with other materials and structures without deviating from the spirit of the invention. The invention as claimed is thus intended to include, among other things, the particular examples and preferred embodiments described herein, as well as alternatives resulting from equivalent modifications and substitutions. It is to be understood that the various theories as to why the invention works are not intended to be limiting.

Claims

1. An organic vapor jet printing (OVJP) deposition system comprising: a plurality of OVJP print bars each comprising one or more OVJP print dies; a float table comprising: one or more substrate clamps configured to hold a substrate having a first active surface and to adjust a position of the substrate on the float table at at least two motion angles; and one or more controls arranged to provide control over the one or more substrate clamps; and one or more sensors configured to measure an alignment of a substrate on the float table with the plurality of OVJP print bars; wherein a height of each of the plurality of OVJP print bars is adjustable independently of each of the other OVJP print bars of the plurality of OVJP print bars; wherein the float table is movable in a zone extending below the plurality of OVJP print bars; and wherein the substrate is movable on the float table independently of movement of the float table below the plurality of OVJP print bars.

2. The OVJP deposition system of claim 1, further comprising a height control subsystem configured to control a relative distance of the plurality of OVJP print bars above the float table.

3. The OVJP deposition system of claim 1, wherein the float table comprises a pressure-vacuum (PV) float table.

4. The OVJP deposition system of claim 1, wherein the one or more substrate clamps are controlled by the float table such that movement of the substrate clamps is determined at least in part by movement of the float table.

5. The OVJP deposition system of claim 1, wherein the one or more sensors comprise an alignment camera configured to align the substrate with the plurality of OVJP print bars.

6. The OVJP deposition system of claim 1, wherein at least one of the plurality of OVJP print bars is redundant to at least one other print bar of the plurality of OVJP print bars for printing on a same area of the substrate.

7. The OVJP deposition system of claim 1, wherein the substrate, when processed by the OVJP deposition system, does not contact any physical surface other than the one or more substrate clamps.

8. The OVJP deposition system of claim 1, wherein the float table provides cooling for the substrate.

9. The OVJP deposition system of claim 1, wherein one or both of the float table and the plurality of OVJP print bars is rotatable relative to the other.

10. A method of operating an OVJP deposition system according to any one of claims 1-9, the method comprising: obtaining a substrate; placing the substrate on a float table and securing a position of the substrate using one or more clamps; adjusting the position of the substrate on the float table via the one or more clamps; moving the float table and the substrate to a position in the OVJP deposition system where the substrate is disposed below a print bar of the OVJP deposition system; ejecting material from the printbar to be deposited on the substrate; and moving the floatation table to a position in the OVJP deposition system where the substrate is not positioned under a printbar of the OVJP deposition system.

11. The method of claim 10, wherein the floatation table, the substrate, or both are moved within the OVJP deposition system when the material is ejected from the printbar.

12. The method of claim 10, wherein the position of the substrate on the floatation table is adjustable independent of movement of the floatation table.

13. The method of claim 10, further comprising: receiving a signal from a position sensor indicative of a relative position of the substrate with respect to the printbar; and adjusting the position of the substrate on the floatation table, the position of the floatation table with respect to the printbar, or both in response to the signal.

14. The method of claim 13, wherein the steps of adjusting the position of the substrate on the floatation table, the position of the floatation table with respect to the printbar, or both are performed automatically by a computerized adjustment system.

15. The method of claim 10, further comprising adjusting a height of the substrate on the floatation table, the height of the floatation table with respect to the printbar, or both.

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