Organic vapor jet printing system

Abstract

To provide a depositing system and method that prevent an unsupported portion of a substrate from sagging within the system even when the substrate is, for example, a very large glass substrate.SOLUTION: Systems and methods for depositing materials on a substrate via OVJP are provided. A float table 405 and grippers are used to move and position the substrate relative to one or more OVJP print bars 412 to reduce the risk of damaging or compromising the substrate or prior depositions.SELECTED DRAWING: Figure 4B

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the benefit of priority of U.S. Patent Application No. 63 / 126,475, filed on December 16, 2020, the entire disclosure of which is incorporated herein by reference.

[0002] The present invention relates to devices and techniques for fabricating organic optoelectronic devices such as organic light - emitting diodes, and devices and techniques including the same.

Background Art

[0003] Optoelectronic devices using organic materials are becoming increasingly desirable for many reasons. Many of the materials used to fabricate such devices are relatively inexpensive, so organic optoelectronic devices have the potential for cost - advantage over inorganic devices. In addition, due to the inherent properties of organic materials such as flexibility, the materials can be well - suited for specific applications such as fabrication on flexible substrates. Examples of organic optoelectronic devices include organic light - emitting diodes / devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, organic materials can have performance advantages over conventional materials. For example, the wavelength of light emitted by an organic light - emitting layer can usually be easily adjusted by appropriate dopants.

[0004] OLEDs utilize thin organic films that emit light when a voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in applications such as flat - panel displays, lighting, and backlighting. Some OLED materials and configurations are described in Patent Documents 1 - 3, the entire disclosures of which are incorporated herein by reference.

[0005] One application of phosphorescent molecules is in full-color displays. Industry standards for such displays require pixels adapted to emit specific colors, known as "saturated" colors. In particular, these standards require saturated red, green, and blue pixels. Alternatively, OLEDs can be designed to emit white light. Conventional liquid crystal displays emit light from a white backlight, which is filtered using absorption filters to produce red, green, and blue light. Similar techniques can be used with OLEDs. White OLEDs can be either single-layer EML devices or stacked structures. Color can be measured using CIE coordinates, which are well known in the art.

[0006] As used herein, the term “organic” includes polymeric and low-molecular-weight organic materials that can be used to fabricate organic optoelectronic devices. “Low-molecular-weight” refers to any organic material that is not a polymer, and “low-molecular-weight” can actually be quite large. Low-molecular-weight may include repeating units in some contexts. For example, using long-chain alkyl groups as substituents does not exclude molecules from the “low-molecular-weight” class. Low-molecular-weight may be incorporated into polymers, for example, as pendant groups on a polymer backbone, or as part of said backbone. Low-molecular-weight may also serve as the core portion of a dendrimer, which consists of a series of chemical shells constructed on a core portion. The core portion of a dendrimer may be a fluorescent or phosphorescent low-molecular-weight emitter. Dendrimers can also be “low-molecular-weight,” and all dendrimers currently used in the field of OLEDs are considered to be low-molecular-weight.

[0007] In this specification, “top” means the part furthest from the substrate, while “bottom” means the part closest to the substrate. When it is stated that the first layer is “placed on top of” the second layer, the first layer is located further from the substrate. There may be other layers between the first and second layers unless it is specified that the first layer is “in contact with” the second layer. For example, a cathode may be described as “placed on top of” the anode, even if there are various organic layers in between.

[0008] As used herein, “solution processable” means that it can be dissolved, dispersed or transported in any liquid medium, either in solution or suspension form, and / or deposited from said medium.

[0009] A ligand may be referred to as "photoactive" if it is considered to directly contribute to the photoactive properties of the light-emitting material. A ligand may be referred to as "auxiliary" if it is not considered to contribute to the photoactive properties of the light-emitting material, although auxiliary ligands can alter the properties of photoactive ligands.

[0010] As used herein, as will be generally understood by those skilled in the art, the first “highest occupied molecular orbital” (HOMO) or “lowest empty molecular orbital” (LUMO) energy level is “greater than” or “higher than” the second HOMO or LUMO energy level, if the first energy level is close to the vacuum energy level. Since the ionization potential (IP) is measured as a negative energy relative to the vacuum level, a higher HOMO energy level corresponds to an IP with a smaller absolute value (less negative IP). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) with a smaller absolute value (less negative EA). In a conventional energy level diagram with the vacuum level at the top, the LUMO energy level of a material is higher than the HOMO energy level of the same material. “Higher” HOMO or LUMO energy levels appear to be closer to the top of such a diagram than “lower” HOMO or LUMO energy levels.

[0011] As used herein, as will be generally understood by those skilled in the art, if the first work function has a higher absolute value, then the first work function is "greater than" or "higher than" the second work function. Since work functions are generally measured as negative numbers relative to the vacuum level, this means that a "higher" work function is even more negative. In a conventional energy level diagram with the vacuum level at the top, a "higher" work function is illustrated as being far away from the vacuum level in the downward direction. Thus, the definitions of the HOMO and LUMO energy levels follow a different convention than that of the work function.

[0012] Layers, materials, regions, and devices may be described herein in reference to the color of light they emit. Generally, a light-emitting region described herein as producing light of a particular color may include one or more light-emitting layers arranged on top of each other as a laminate.

[0013] In this specification, a “red” layer, material, region, or device means one that emits light in the range of approximately 580–700 nm or has a maximum peak in its emission spectrum in that range. Similarly, a “green” layer, material, region, or device means one that emits light in the range of approximately 500–600 nm or has an emission spectrum with a peak wavelength in this range, a “blue” layer, material, or device means one that emits light in the range of approximately 400–500 nm or has an emission spectrum with a peak wavelength in this range, and a “yellow” layer, material, region, or device means one that has an emission spectrum with a peak wavelength in the range of approximately 540–600 nm. In some arrays, another region, layer, material, region, or device may separately provide “deep blue” and “light blue” light. In this specification, in arrays that separately provide “light blue” and “deep blue,” the “deep blue” component means that the peak emission wavelength is at least approximately 4 nm shorter than the peak emission wavelength of the “light blue” component. Typically, the "light blue" component has a peak emission wavelength in the range of approximately 465–500 nm, and the "deep blue" component has a peak emission wavelength in the range of approximately 400–470 nm, although these ranges can vary depending on the configuration. Similarly, a color conversion layer refers to a layer that converts or changes light of another color to light having wavelengths specified by that color. For example, a "red" color filter refers to a filter that provides light with wavelengths in the range of approximately 580–700 nm. Generally, there are two classes of color conversion layers: color filters that modify the spectrum by removing unwanted wavelengths of light, and color changing layers that convert high-energy photons to low-energy ones. A "color" component refers to a component that, when activated or used, produces or emits light having the aforementioned specific color. For example, "first emission region of first color" and "second emission region of second color different from first color" describe two emission regions that, when activated within a device, emit two different colors as described above.

[0014] In this specification, luminescent materials, luminescent layers, and luminescent regions can be distinguished from each other and from other structures based on the light initially generated by the material, layer, or region, rather than the light ultimately emitted by the same or different structures. The generation of initial color is typically the result of a change in energy levels leading to the emission of photons. For example, an organic luminescent material may initially generate blue light, which can be converted to red or green light by a color filter, quantum dot, or other structure, resulting in the completed luminescent layer or sub-pixel emitting red or green light. In this case, the initial luminescent material or layer may be referred to as the "blue" component, even if the sub-pixel is the "red" or "green" component.

[0015] In some cases, it may be preferable to describe the color of components such as luminescent regions, subpixels, and color conversion layers based on 1931 CIE coordinates. For example, a yellow luminescent material may have multiple peak emission wavelengths, one at or near the edge of the aforementioned "green" region, and another within or near the edge of the "red" region. Thus, in this specification, each color term also corresponds to a shape in the 1931 CIE coordinate color space. A shape in the 1931 CIE color space is formed by following a trajectory between two color points and any further internal points. For example, the internal shape parameters for red, green, blue, and yellow can be defined as follows. [Table 1]

[0016] Further details regarding OLEDs and the definitions described herein can be found in Patent Document 4, which is incorporated herein by reference in its entirety. [Overview of the Initiative]

[0017] According to the embodiments, organic light-emitting diodes / devices (OLEDs) are also provided. An OLED may include an anode, a cathode, and an organic layer disposed between the anode and the cathode. According to the embodiments, the organic light-emitting device is incorporated into one or more devices selected from consumer products, electronic component modules, and / or lighting panels.

[0018] Embodiments disclosed herein provide a deposition system comprising: one or more print bars, which may be of the OVJP type; a float table including one or more substrate grippers; and one or more control devices arranged to provide control over the one or more substrate grippers, wherein each of the one or more print bars includes one or more print heads, and the one or more substrate grippers are configured to hold a substrate and adjust the position of the substrate on the float table by a movement of at least 2°. The system may include one or more sensors for measuring the alignment of the substrate on the float table with respect to the one or more OVJP print bars. The float table may extend throughout the system so as to extend before and after the print bars, or the float table may be movable in a region extending below the one or more OVJP print bars. The substrate may be movable on the float table independently of the movement of the float table below the one or more OVJP print bars, for example, to allow fine adjustment of the position of the substrate on the float table.

[0019] Embodiments also provide a method of operating a deposition system by obtaining a substrate; placing the substrate on a float table and fixing and adjusting the position of the substrate using one or more grippers. The float table and / or the substrate can move through the system, or the substrate can move across the float table and through a region below a print bar, such as an OVJP print bar of the deposition system. While the substrate is moving through the system, material can be ejected from the print bar and deposited onto the substrate. After deposition, the float table and / or the substrate can move to a position where the substrate is not below the print bar.

Brief Description of the Drawings

[0020] [Figure 1] Figure 1 shows an organic light emitting device structure that can be fabricated using the devices and techniques disclosed herein.

[0021] [Figure 2] Figure 2 shows an exemplary structure of an inverted organic light emitting device without another electron transport layer that can be fabricated using the devices and techniques disclosed herein.

[0022] [Figure 3A] Figure 3A shows an example of a print engine disclosed herein.

[0023] [[ID=2……]] [Figure 3B] Figure [Figure 3B] shows an example of a system using a print bar with multiple print engines operating at the print head level disclosed herein.

[0024] [Figure 3C] Figure 3C shows an example of a system using a single print engine operating at the print bar level disclosed herein.

[0025] [Figure 3D] Figure 3D shows an exploded view of the die manifold, heat shield, and related components disclosed herein.

[0026] [Figure 3E] Figure 3E shows an exemplary arrangement of the print bars disclosed herein. [Figure 3F] Figure 3F shows an exemplary arrangement of the print bar disclosed herein.

[0027] [Figure 4A] Figure 4A shows an exemplary top view of an OVJP deposition system according to an embodiment disclosed herein. [Figure 4B] Figure 4B shows a side view of an exemplary OVJP deposition system according to an embodiment disclosed herein.

[0028] [Figure 4C] Figure 4C shows a top view, side view, and front view of a substrate PV table according to an embodiment disclosed herein.

[0029] [Figure 4D] Figure 4D shows a front view of the OVJP deposition system shown in Figures 4A to 4C, arranged in a vacuum chamber, according to an embodiment disclosed herein.

[0030] [Figure 4E] Figure 4E shows an exemplary OVJP system in which a print bar is immersed in a PV table, according to an embodiment disclosed herein.

[0031] [Figure 5A] Figure 5A shows a side view of an embodiment disclosed herein, in which the substrate and printed circuit board are arranged in a vertically inverted manner compared to those shown in Figures 4A to 4E. [Figure 5B] Figure 5B shows a front view of an embodiment disclosed herein, in which the substrate and printed circuit board are arranged in a vertically inverted manner compared to those shown in Figures 4A to 4E.

[0032] [Figure 6] Figure 6 shows an example of a deposition system in which the substrate enters with the active side facing downward and moves on a stationary PV table extending through the system according to the embodiments disclosed herein.

[0033] [Figure 7] Figure 7 shows an exemplary system similar to that in Figure 6, but the substrate is arranged so that the active side faces upward, according to the embodiments disclosed herein.

[0034] [Figure 8] Figure 8 shows an example of a deposition system in which the substrate is positioned with the active side facing downwards, similar to the example in Figure 6, but the inactive reverse side of the substrate is held by an upper PV table according to the embodiment disclosed herein.

[0035] [Figure 9] Figure 9 shows a front view of an exemplary deposition system in which, as shown in Figures 6 and 7, the substrate is not supported on an air table when entering the system, but instead is held from above by a vacuum chuck or similar device with the active side facing downward, according to embodiments disclosed herein. [Modes for carrying out the invention]

[0036] Generally, an OLED includes at least one organic layer positioned between the anode and cathode and electrically connected to them. When an electric current is applied, the anode injects holes and the cathode injects electrons into the organic layer(s). The injected holes and electrons move to the oppositely charged electrodes, respectively. When electrons and holes are localized on the same molecule, an "exciton" is formed, which is a localized electron-hole pair with an excited energy state. Light is emitted via a photoemission mechanism when the exciton relaxes. In some cases, excitons may be localized on an excimer or exciplex. Non-radiative mechanisms such as thermal relaxation may occur, but these are generally considered undesirable.

[0037] Early OLEDs used light-emitting molecules ("fluorescent") that emitted light from their singlet state, as disclosed, for example, in U.S. Patent No. 4,769,292, which is incorporated by reference in its entirety. Fluorescence emission generally occurs within a timeframe of less than 10 nanoseconds.

[0038] More recently, OLEDs with light-emitting materials ("phosphorescent") that emit light from a triplet state have been demonstrated. See, in their entirety, Baldo et al., "Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices," Nature, Vol. 395, pp. 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"). Phosphorescence is described in further detail in U.S. Patent No. 7,279,704, paragraphs 5-6, which is also referenced.

[0039] Figure 1 shows an organic light-emitting device 100. The figure is not necessarily to a constant scale. The device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, a light-emitting 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 composite cathode having a first conductive layer 162 and a second conductive layer 164. The device 100 can be fabricated by sequentially depositing the described layers. The properties and functions of these various layers, as well as examples of materials, are described in further detail in paragraphs 6-10 of U.S. Patent No. 7,279,704, which is incorporated by reference.

[0040] Further examples are available for each of these layers. For example, flexible and transparent substrate-anode combinations are 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 in a 50:1 molar ratio, as disclosed in U.S. Patent Application Publication No. 2003 / 0230980, which is incorporated by reference in its entirety. Examples of luminescent and host materials are disclosed in U.S. Patent No. 6,303,238 by Thompson et al., which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li in a 1:1 molar ratio, 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 whole reference, disclose examples of cathodes including composite cathodes having a thin layer of metal such as Mg:Ag with a transparent, conductive, sputtered ITO layer covering it. The theory and use of blocking layers are described in more detail in U.S. Patent Nos. 6,097,147 and U.S. Patent Application Publication 2003 / 0230980, incorporated by whole reference. Examples of injection layers are provided in U.S. Patent Application Publication 2004 / 0174116, incorporated by whole reference. A description of protective layers can be found in U.S. Patent Application Publication 2004 / 0174116, incorporated by whole reference.

[0041] Figure 2 shows an inverted OLED 200. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole transport layer 225, and an anode 230. Device 200 can be fabricated by depositing the described layers in order. The most common OLED configuration has a cathode positioned above the anode, and since device 200 has a cathode 215 positioned below the anode 230, device 200 can be referred to as an "inverted" OLED. The same materials described for device 100 may be used in the corresponding layers of device 200. Figure 2 provides an example of how some layers may be omitted from the structure of device 100.

[0042] The simple layered structures illustrated in Figures 1 and 2 are provided as non-limiting examples, and it is understood that embodiments of the present invention may be used in relation to a wide variety of other structures. The specific materials and structures described are substantially illustrative, and other materials and structures may be used. Functional OLEDs may be realized by combining the various layers described in various ways, or layers may be omitted entirely based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Many of the examples provided herein describe various layers as containing a single material, but it is understood that combinations of materials, such as host and dopant mixtures, or more generally, mixtures, may be used. Furthermore, layers may have various sublayers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, the hole transport layer 225 transports holes and injects them into the light-emitting layer 220, and may be described as a hole transport layer or hole injection layer. In one embodiment, the OLED may be described as having an “organic layer” positioned between the cathode and the anode. The organic layer may consist of a single layer or may further consist of multiple layers of different organic materials, for example, as described with respect to Figures 1 and 2.

[0043] Structures and materials not specifically described may be used, such as OLEDs (PLEDs) composed of polymer materials, as disclosed in U.S. Patent No. 5,247,190 by Friend et al., which is incorporated in whole by reference. Further examples include OLEDs having a single organic layer. OLEDs may be stacked, for example, as described in U.S. Patent No. 5,707,745 by Forrest et al., which is incorporated in whole by reference. OLED structures may deviate from the simple layered structures illustrated in Figures 1 and 2. For example, the substrate may include angled reflective surfaces to improve outcoupling, such as the mesa structure described in U.S. Patent No. 6,091,195 by Forrest et al., which is incorporated in whole by reference, and / or the recessed structure described in U.S. Patent No. 5,834,893 by Bulovic et al.

[0044] In some embodiments disclosed herein, light-emitting layers or materials such as light-emitting layer 135 and light-emitting layer 220 shown in Figures 1 and 2, respectively, may include quantum dots. Unless otherwise indicated expressly or by context as understood by those skilled in the art, “light-emitting layer” or “light-emitting material” disclosed herein may include organic light-emitting materials and / or light-emitting materials that include quantum dots or equivalent structures. Such light-emitting layers may include only quantum dot materials that convert light emitted by another light-emitting material or other light emitter, or they may also include the other light-emitting material or other light emitter, or they may emit light itself directly from the application of an electric current. Similarly, color conversion layers, color filters, upconversion layers or structures, or downconversion layers or structures may include materials that include quantum dots, but such layers may not be considered “light-emitting layers” as disclosed herein. Generally, an "emissive layer" or material emits initial light and does not emit initial light within the device, but can be converted by other layers such as color filters or other color conversion layers that re-emit light with a different spectral content based on the initial light emitted by the emissive layer.

[0045] Unless otherwise specified, any of the layers of the various embodiments may be deposited by any suitable method. For organic layers, preferred methods include deposition by thermal deposition, such as those described in U.S. Patent Nos. 6,013,982 and 6,087,196, which are incorporated by reference; inkjet deposition; organic vapor deposition (OVPD), such as those described in U.S. Patent No. 6,337,102 by Forrest et al., which are incorporated by reference; and OVJP, such as those described in U.S. Patent No. 7,431,968, which are incorporated by reference. Other suitable deposition methods include spin coating and other solution-based processes. Solution-based processes are preferably carried out in a nitrogen or inert atmosphere. For other layers, preferred methods include thermal deposition. Preferred patterning methods include those described in U.S. Patents No. 6,294,398 and No. 6,468,819, which are incorporated in whole by reference, as well as patterning related to several deposition methods such as inkjet and organic vapor jet printing (OVJP). Other methods may be used. The material to be deposited may be modified to suit a particular deposition method. For example, substituents such as alkyl and aryl groups, which are branched or unbranched and preferably contain at least three carbon atoms, may be used in low molecular weight materials to enhance their ability to undergo solution processing. Substituents with 20 or more carbon atoms may be used, with 3 to 20 carbon atoms being a preferred range. Materials with asymmetric structures may have better solution processability than those with symmetric structures because asymmetric materials may be less prone to recrystallization. Dendrimer substituents may be used to enhance the ability of low molecular weight materials to undergo solution processing.

[0046] Devices fabricated according to embodiments of the present invention may further include a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from damaging exposure to harmful species in the environment, including moisture, vapors and / or gases. The barrier layer may be deposited on, below, or next to the substrate, electrodes, or on any other part of the device, including edges. The barrier layer may consist of a single layer or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques and may include single-phase and multi-phase compositions. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate inorganic or organic compounds or both. Preferred barrier layers include mixtures of polymer and non-polymer materials, as described in U.S. Patent No. 7,968,146, PCT Patent Application No. PCT / US2007 / 023098 and PCT / US2009 / 042829, which are incorporated herein by reference in their entirety. For a mixture to be considered a "mixture," the polymer and non-polymer materials, including the barrier layer, should be deposited under the same reaction conditions and / or simultaneously. The weight ratio of the polymer material to the non-polymer material can be in the range of 95:5 to 5:95. The polymer and non-polymer materials may be made from the same precursor material. In one example, the mixture of polymer and non-polymer materials essentially consists of polymer silicon and inorganic silicon.

[0047] In some embodiments, at least one of the anode, cathode, or new layer placed on top of the organic light-emitting layer functions as an enhancement layer. The enhancement layer includes a plasmon material that non-radiatively bonds to the light-emitting material and exhibits surface plasmon resonance, transferring excited state energy from the light-emitting material to non-radiative mode surface plasmon polaritons. The enhancement layer is located within a threshold distance from the organic light-emitting layer, and the light-emitting material has a total non-radiative decay rate constant and a total radioactive decay rate constant in the presence of the enhancement layer, where, at the threshold distance, the total non-radiative decay rate constant is equal to the total radioactive decay rate constant. In some embodiments, the OLED further includes an outcoupling layer. In some embodiments, the outcoupling layer is located on top of the enhancement layer opposite the organic light-emitting layer. In some embodiments, the outcoupling layer is located on the opposite side of the light-emitting layer from the enhancement layer, but still outcouples energy from the surface plasmon modes of the enhancement layer. The outcoupling layer scatters energy from surface plasmon polaritons. In some embodiments, this energy is scattered into free space as photons. In other embodiments, the energy is scattered from the surface plasmon mode to other modes of the device, such as organic waveguide modes, substrate modes, or other waveguide modes, etc. If the energy is scattered to non-free-space modes of the OLED, other outcoupling schemes can be incorporated to extract that energy into free space. In some embodiments, one or more intervening layers can be placed between the enhancement layer and the outcoupling layer. Examples of intervening layers can be dielectric materials including organic, inorganic, perovskite, and oxide materials, and may include laminates and / or mixtures of these materials.

[0048] An enhancement layer alters the effective properties of the medium in which the light-emitting material resides, resulting in one or all of the following: a decrease in luminescence, a change in the shape of the light-emitting line, a change in light-emitting intensity with respect to angle, a change in the stability of the light-emitting material, a change in the efficiency of the OLED, and a decrease in the efficiency roll-off of the OLED device. Placing the enhancement layer on the cathode side, the anode side, or both sides results in an OLED device that takes advantage of any of the aforementioned effects. In addition to the specific functional layers shown in the various OLED examples described and illustrated herein, the OLEDs of this disclosure may include any of the other functional layers commonly found in OLEDs.

[0049] The enhancement layer may consist of a plasmon material, an optically active metamaterial, or a hyperbolic metamaterial. As used herein, a plasmon material is a material whose real part of dielectric constant crosses zero in the visible or ultraviolet region of the electromagnetic spectrum. In some embodiments, the plasmon material comprises at least one metal. In such embodiments, the metal may include at least one of Ag, Al, Au, Ir, Pt, Ni, Cu, W, Ta, Fe, Cr, Mg, Ga, Rh, Ti, Ru, Pd, In, Bi, Ca, alloys or mixtures of these materials, and laminates of these materials. Generally, a metamaterial is a medium composed of different materials, where the medium as a whole behaves differently from the sum of its individual material parts. In particular, an optically active metamaterial is defined as a material having both a negative dielectric constant and a negative magnetic permeability. A hyperbolic metamaterial, on the other hand, is an anisotropic medium in which the dielectric constant or magnetic permeability has different signs for different spatial directions. Optically active metamaterials and hyperbolic metamaterials are distinctly different from many other photonic structures, such as distributed Bragg reflectors ("DBRs"), in that they are media that appear uniform in the direction of propagation on a wavelength scale. Using terminology understandable to those skilled in the art, the dielectric constant of a metamaterial in the direction of propagation can be described by the effective medium approximation. Plasmon and metamaterials provide a way to control the propagation of light and can improve OLED performance in various ways.

[0050] In some embodiments, the enhancement layer is provided as a flat layer. In other embodiments, the enhancement layer has periodically, quasi-periodic, or randomly arranged wavelength-size features, or periodically, quasi-periodic, or randomly arranged sub-wavelength-size features. In some embodiments, the wavelength-size features and sub-wavelength-size features have sharp edges.

[0051] In some embodiments, the outcoupling layer has periodically, quasi-periodic, or randomly arranged wavelength-size features, or periodically, quasi-periodic, or randomly arranged sub-wavelength-size features. In some embodiments, the outcoupling layer may consist of a plurality of nanoparticles, and in other embodiments, the outcoupling layer may consist of a plurality of nanoparticles placed on a material. In these embodiments, the outcoupling may be tunable by at least one of varying the size of the plurality of nanoparticles, varying the shape of the plurality of nanoparticles, varying the material of the plurality of nanoparticles, adjusting the thickness of the material, varying the refractive index of the material or the refractive index of any further layer placed on the plurality of nanoparticles, varying the thickness of an enhancement layer, and / or varying the material of the enhancement layer. The plurality of nanoparticles in the device may be formed from at least one of metals, dielectric materials, semiconductor materials, alloys of metals, mixtures of dielectric materials, laminates or layers of one or more materials, and / or a core of one type of material coated with a shell of another type of material. In some embodiments, the outcoupling layer is composed of at least metal nanoparticles, the metal being 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 laminates of these materials. Multiple nanoparticles may have further layers arranged on top of them. In some embodiments, the polarization of the emission can be tuned using the outcoupling layer. By changing the dimension and periodicity of the outcoupling layer, the type of polarization that is preferentially outcoupled to air can be selected. In some embodiments, the outcoupling layer also functions as an electrode in the device.

[0052] The internal quantum efficiency (IQE) of fluorescent OLEDs is thought to exceed the 25% spin statistical limit through delayed fluorescence. In this specification, there are two types of delayed fluorescence: P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence is produced by triplet-triplet annihilation (TTA).

[0053] On the other hand, E-type delayed fluorescence does not depend on collisions between two triplet states, but rather on the thermal population between the triplet and singlet states. Compounds capable of producing E-type delayed fluorescence must have a very small singlet-triplet gap. Thermal energy can activate the transition from the triplet state to the singlet state. This type of delayed fluorescence is also known as thermally activated delayed fluorescence (TADF). A characteristic feature of TADF is that the delayed component increases with increasing temperature due to the increase in thermal energy. If the reverse intersystem crossing rate is fast enough to minimize non-radiative decay from the triplet state, the fraction of back-populated singlet excited states can reach 75%. The total singlet fraction can reach 100%, which is far above the spin statistical limit.

[0054] E-type delayed fluorescence properties can be observed in excyplex systems or single compounds. While not constrained by any theory, it is believed that a small singlet-triplet energy gap (ΔES-T) is necessary for the luminescent material to produce E-type delayed fluorescence. Metal-free organic donor-acceptor luminescent materials can achieve this. The emission of these materials is often characterized as donor-acceptor charge transfer (CT) emission. Spatial separation of the HOMO and LUMO in these donor-acceptor compounds often reduces ΔES-T. These states may be involved in the CT state. In many cases, donor-acceptor luminescent materials are constructed by linking an electron-donating moiety, such as an amino or carbazole derivative, with an electron-accepting moiety, such as an N-containing six-membered aromatic ring.

[0055] Devices fabricated according to embodiments of the present invention can be incorporated into a wide variety of electronic component modules (or units) that can be incorporated into various electronic products or intermediate components. Examples of such electronic products or intermediate components include display screens and lighting devices (such as discrete light source devices or lighting panels) that can be used by end-user product manufacturers. Such electronic component modules may optionally include drive electronics and / or power supplies. Devices fabricated according to embodiments of the present invention can be incorporated into a wide variety of consumer products having one or more incorporated electronic component modules (or units). A consumer product is disclosed that includes an OLED with the compounds of this disclosure in its organic layer. Such a consumer product includes any type of product that includes one or more light sources and / or one or more of the following types of visual displays. Some examples of such consumer products include flat panel displays, curved displays, computer monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting and / or signal transmission, head-up displays, fully or partially transparent displays, flexible displays, displays that can be rolled up, displays that can be folded, displays that can be stretched, laser printers, telephones, mobile phones, tablets, phablets, personal digital assistants (PDAs), wearable devices, laptop computers, digital cameras, camcorders, viewfinders, microdisplays (displays less than 2 inches diagonally), 3-D displays, virtual reality or augmented reality displays, vehicles, video walls including multiple displays arranged together, theater or stadium screens, and billboards. Devices manufactured according to the present invention can be controlled using various control mechanisms, including passive matrices and active matrices. Many of the devices are intended for use within a human-comfortable temperature range, such as 18 to 30 degrees Celsius, more preferably room temperature (20 to 25 degrees Celsius), but can also be used outside this temperature range, for example, -40 to +80 degrees Celsius.

[0056] The materials and structures described herein may have applications in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors may use these materials and structures. More generally, organic devices such as organic transistors may use these materials and structures.

[0057] In some embodiments, the OLED has one or more properties selected from the group consisting of being flexible, rollable, foldable, stretchable, and bendable. In some embodiments, the OLED is transparent or translucent. In some embodiments, the OLED further includes a layer containing carbon nanotubes.

[0058] In some embodiments, the OLED further includes a layer containing a delayed fluorescence emitter. In some embodiments, the OLED includes an RGB pixel array or a white and color filter pixel array. In some embodiments, the OLED is a mobile device, a handheld device, or a wearable device. In some embodiments, the OLED is a display panel having a diagonal of less than 10 inches or an area of ​​less than 50 square inches. In some embodiments, the OLED is a display panel having a diagonal of at least 10 inches or an area of ​​at least 50 square inches. In some embodiments, the OLED is an illumination panel.

[0059] In some embodiments of the light-emitting region, the light-emitting region further includes a host.

[0060] In some embodiments, the compound may be a luminescent dopant. In some embodiments, the compound may generate luminescence via phosphorescence, fluorescence, thermally activated delayed fluorescence (TADF, also known as E-type delayed fluorescence), triplet-triplet annihilation, or a combination of these processes.

[0061] The OLEDs disclosed herein can be incorporated into one or more consumer products, electronic component modules, and lighting panels. The organic layer may be an emissive layer, and in some embodiments, the compound may be an emissive dopant, and in other embodiments, the compound may be a non-emissive dopant.

[0062] The organic layer may also contain a host. In some embodiments, two or more hosts are preferred. In some embodiments, the host used may be a) bipolar, b) electron-transporting, c) host-transporting, or d) a wide-bandgap material that contributes little to charge transport. In some embodiments, the host may include a metal complex. The host may be an inorganic compound.

[0063] Combination with other materials Materials described herein as useful for specific layers in organic light-emitting devices may be used in combination with a wide variety of other materials present in the device. For example, the light-emitting dopants disclosed herein may be used in combination with a wide variety of hosts, transport layers, blocking layers, injection layers, electrodes, and other possible layers. The materials described or referenced below are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and those skilled in the art can easily consult the literature to identify other materials that may be useful in combination.

[0064] Various materials can be used for the various luminescent and non-luminescent layers and arrangements disclosed herein. Examples of preferred materials are disclosed in U.S. Patent Application Publication No. 2017 / 0229663, which is incorporated herein by reference in its entirety.

[0065] Conductive dopants: Charge transport layers are doped with conductive dopants, significantly altering the density of charge carriers and thereby changing their conductivity. Conductivity is increased by generating charge carriers in the matrix material or, depending on the type of dopant, and changes in the Fermi level of the semiconductor can also be achieved. Hole transport layers can be doped with p-type conductive dopants, while n-type conductive dopants are used in electron transport layers.

[0066] HIL / HTL: The hole injection / transport material used in the present invention is not particularly limited, and any compound may be used as long as the compound is typically used as a hole injection / transport material.

[0067] EBL: An electron blocking layer (EBL) can be used to reduce the number of electrons and / or excitons emitted from the light-emitting layer. The presence of such a blocking layer in a device can result in significantly higher efficiency and / or a longer lifetime compared to a similar device lacking a blocking layer. A blocking layer can also be used to restrict light emission to a desired region 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 light-emitting element 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 embodiment, the compound used in the EBL contains the same molecule or the same functional group as one of the hosts described below.

[0068] host: The light-emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as a light-emitting material, and may include a host material using the metal complex as a dopant material. The host material is 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 met.

[0069] HBL: A hole blocking layer (HBL) can be used to reduce the number of holes and / or excitons emitting from the light-emitting layer. The presence of such a blocking layer in a device can result in significantly higher efficiency and / or a longer lifetime compared to a similar device lacking a blocking layer. A blocking layer can also be used to restrict light emission to a desired region of the OLED. In some embodiments, the HBL material has a lower HOMO (further away from the vacuum level) and / or a higher triplet energy than the light-emitting material closest to the HBL interface. In some embodiments, the HBL material has a lower HOMO (further away from the vacuum level) and / or a higher triplet energy than one or more hosts closest to the HBL interface.

[0070] ETL: An electron transport layer (ETL) may include a material capable of transporting electrons. The electron transport layer may be intrinsic (undoped) or doped. Doping can be used to enhance conductivity. Examples of ETL materials are not particularly limited, and any metal complex or organic compound may be used, as long as it is typically used for electron transport.

[0071] Charge Generation Layer (CGL) In tandem or stacked OLEDs, the transport layer (CGL) plays a crucial role in performance, consisting of an n-doped layer and a p-doped layer for electron and hole injection, respectively. Electrons and holes are supplied from 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, after which the bipolar current gradually stabilizes. Typical CGL materials include n-type and p-type conductive dopants used in the transport layer.

[0072] As previously disclosed, conventional OVJP processes typically involve the distribution of organic materials, such as active organic AMOLED materials, into a heated gaseous mixture via a print nozzle. Conventional OVJP processes typically use pressures in the range of 10 Torr to 1 Atm (760 Torr). Print nozzles can be manufactured using micro-electromechanical (MEMS), micromachining, 3D printing, or similar processes. While exemplary structures of OVJP depositor devices are provided herein, generally, a “print bar” disclosed herein may include one or more “print heads,” each containing at least one print die. A print head typically includes interfaces to each print die within the print head, such as mechanical mounts, gas supply, exhaust interfaces, and heating components. Using multiple print heads on a print bar may, for example, enable simultaneous printing of multiple pixels on a substrate. To facilitate the deposition process, the print bar itself may be heated.

[0073] Embodiments disclosed herein provide various systems and techniques that enable efficient transport of substrates passing through one or more print bars in a deposition chamber, while allowing precise and efficient control of the proximity between the substrate and the print bar. This can enable precise control of the thickness and uniformity of layers printed in the system, which may vary depending on the application. For example, display panels of different sizes and types may require different thicknesses, tolerances, etc. The print bar and substrate may also be movable relative to each other, for example, so that the print bar is positioned perpendicular or parallel to the substrate, or so that the substrate or system is positioned at any other desired angle with respect to the principal y-axis, for example. The substrate may also rotate or translate in other directions during processing, i.e., while the substrate is moving in the system in the principal y-direction. For example, when printing subpixels or similar features, the material can be printed along the y-axis, and after the subpixels or sets of subpixels have been printed, the substrate may be moved in another direction, for example, by shifting the position of one subpixel along the x-direction. Such a process can be used, for example, to print multi-component or multi-color subpixels. As shown and described in the various exemplary arrangements herein, the print bar is typically positioned perpendicular to the direction of movement of the substrate during processing, while the substrate carrier, such as the substrate and / or flat table, can be rotated relative to the print bar. Individual or overlapping print bars or sets of print bars can be used.

[0074] Embodiments disclosed herein provide arrangements in which there is little to no direct physical contact between the substrate on which the material is printed via OVJP and any other surface, or in some embodiments, arrangements in which there is only temporary or transient physical contact. This reduces the possibility of undesirable voltage buildup and / or electrostatic discharge (ESD), minimizing or eliminating damage related to the substrate, pre-deposited layers, and underlying electrical circuits (e.g., display backplane or AMOLED layer). In most deposition systems disclosed herein, the substrate does not physically contact any surface. However, in some embodiments, the substrate may be contacted by a solid moving vacuum chuck on the back (inactive) side of the substrate. When using such a device, ESD minimization techniques such as an ionizer and appropriate ESD-safe techniques for vacuuming and removing the substrate from the chuck can be incorporated.

[0075] The embodiments disclosed herein may be capable of deposition on a range of substrate types and sizes. For example, glass and other materials known for use in OLEDs can be used as substrates on which materials are printed in the systems disclosed herein. Conventional OLED fabrication systems and similar systems can be difficult to operate and print on some substrates, such as very large glass substrates, because the momentum increases as the substrate moves within the system, causing unsupported portions of the substrate to flex. However, physically supporting the substrate at all points is generally undesirable due to the risk of substrate damage or contamination. 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 enable the operation of relatively large and sensitive substrates with a significantly reduced risk of damage and contamination. The embodiments disclosed herein can efficiently operate and deposit materials on substrates with edge measurements of 1 to 5 m or more. Multiple devices can also be manufactured in a single or few passes through the deposition system disclosed herein using a larger substrate called "mother glass," after which the larger substrate is separated into individual devices. For example, current 10th or 11th generation mother glass typically has dimensions of approximately 2940 mm × 3370 mm, and substrates of this size can be successfully operated and processed by the embodiments disclosed herein. More generally, substrates having maximum edge measurements of 1, 2, 3, 4, or 5 m at any aspect ratio can be operated and processed by any embodiment disclosed herein.

[0076] The system disclosed herein can receive an input substrate, i.e., a substrate on which material is deposited via an OVJP, through a pressure-controlled load lock chamber. After the material has been deposited on the substrate, it can be output to the same input lock or another output load lock, enabling integration into various fabrication systems and technologies. For example, the deposition system disclosed herein can be used in inline fabrication systems and processes where the substrate flows in one direction throughout the entire fabrication process.

[0077] Embodiments disclosed herein may include a plurality of print bars, each of which may include one or more print dies and / or smaller print bars, each of which may include one or more print dies. Each print die may be enclosed in a “print engine” disclosed herein. In this specification, 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 of the associated print dies. Generally, a print bar disclosed herein includes one or more print engines.

[0078] The use of multiple print bars allows for greater flexibility in the system compared to conventional systems, such as reduced loading and unloading times and improved print uniformity, enabling the distribution of multiple chemicals within a single process chamber. Furthermore, the use of multiple and / or smaller print bars can enhance flexibility. In some configurations, each of the smaller print bars may be controllable to move perpendicular to the movement of the substrate through the system, parallel to the movement of the substrate, and / or vertically (z) relative to the substrate, i.e., in the direction toward or away from the substrate surface on which the material is deposited.

[0079] The print bars disclosed herein can be located in the width direction of the system so as to extend across the width of the substrate being processed by the system, enabling deposition on any portion of the substrate. When multiple print bars are used, they can be arranged in line or in an alternating arrangement.

[0080] Embodiments disclosed herein enable a range of diverse physical motion controls for the substrate and / or other components of the system, allowing for precise positioning of the substrate relative to the OVJP print nozzle. For example, substrate positioning can be controlled as the substrate passes over one or more print bars using positioning adjustments that are active both in the plane of the substrate and in the vertical direction toward or away from the print bar. Generally, it is preferable to maintain the surface of the substrate in a plane parallel to or essentially parallel to the plane of the OVJP nozzle in the print bar, preferably 1 to 10° or less, preferably less than 5°, and more preferably less than 1°. More generally, embodiments disclosed herein include physical controls that enable precise adjustment of the gap between the print bar and the substrate, thereby allowing the system to maintain the substrate within the deposition process window. Similarly, some or all of the system's motion axes can be synchronized, for example using a real-time controller, to enable precise and harmonized adjustment of the print bar and the substrate. In some embodiments, the substrate can also rotate within the deposition system to cause different orientations of components relative to the deposition material, such as to support different displays and / or backplane orientations on the substrate. The system's various controllable operations allow for multiple passes of a circuit board through one or more print bars, enabling, for example, simultaneous printing with multiple print bars, repetitive continuous printing with one or more print bars, and pattern printing with one or more print bars.

[0081] Embodiments may include a subsystem for inspection and / or calibration that can move through the deposition system along the direction of movement of the substrate as it passes through the print bar. Such a component may enable periodic in-situ inspection and measurement of the print bar and nozzles. For example, the system may be equipped with optical sensors, thermal sensors, and other sensors that can move parallel to the print bar so that any position on the print bar can be inspected. Data collected from print bar inspection can be used, for example, to dynamically adjust the movement of the print bar or substrate, or to perform cleaning as needed. This data can also be used to predict potential malfunctions and enable predictable system maintenance.

[0082] The embodiments may include various components and technologies for managing the heat generated by the high-temperature gas mixture ejected from the OVJP print nozzle and other components.

[0083] The OVJP deposition system disclosed herein can be configured within a vacuum chamber, as with conventional OLED deposition systems such as other types of OVJP systems. In the embodiments disclosed herein, the motion system can be isolated from the vacuum chamber wall, for example, through a conventional atmosphere (outside the chamber) via a strategically positioned feedthrough as disclosed herein.

[0084] As previously disclosed, the OVJP print dies disclosed herein can be enclosed in one or more print bars via a print engine. As used herein, a print engine means a subsystem including one or more print dies, associated interfaces for input and exhaust gas flows, a height sensor (if present), and a height adjustment mechanism (if present). Figures 3A to 3D show examples of print engines disclosed herein. Figure 3A shows an individual print engine. The example in Figure 3A is configured upward, i.e., with the nozzles facing "upwards" (towards the top of the page). It is 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 the direction of gravity relative to the print head. However, in this specification, regardless of the arrangement of components relative to gravity, when the substrate and print bar are arranged such that the material ejected from the OVJP nozzles of the print bar is ejected toward the substrate, the substrate is described as being positioned "below" the print bar and the print bar as being positioned "above" the substrate.

[0085] Figure 3B shows an example of a system using a print bar with multiple print engines operating at the printhead level (i.e., each printhead includes a height sensor and a vertical position control device). Figure 3C shows a similar arrangement with a single print engine operating at the print bar level (i.e., the print bar includes multiple printheads, but has a single vertical position control device for the entire print bar). In Figure 3B, each printhead includes an individual height sensor, whereas in Figure 3C, the print head includes one or more height sensors and a height adjuster that controls the height of the entire bar. As previously disclosed, the print engine may include a print die 307 incorporated into a printhead subassembly 310, as known in OVJP technology, and the printhead subassembly 310 may include one or more heating elements 305, an OVJP delivery nozzle, and other standard OVJP depositor components. An exploded view of the die manifold, heat shield, and other related components is shown in Figure 3D. Whether individual or print bar level height adjusters are used, the print engine may include a height control (z-direction) mechanism 315, such as a lever mounted on an actuator, which may be used to adjust the height and / or orientation of the print head. In embodiments where each print head has an individual height sensor and adjuster, the height sensor 320 may be positioned on the outer edge of the support structure 323, or positioned to allow detection and adjustment of the relative height of the print head to the substrate. The entire assembly may also be supported by a lower support structure 321. A mixing chamber 322 may allow mixing of one or more materials received from the source chamber 325. During the operation of the deposition system, the print die may also be in fluid communication with the exhaust 327, for example, to allow removal of gases and other materials in the area between the print head nozzle and the substrate, and to limit the lateral spread of material ejected from each nozzle to limit or prevent crosstalk between adjacent nozzles. As shown in Figures 3B and 3C, the print bar 301 may include a plurality of print heads 300.The gas input and exhaust interfaces with the print engine are provided via the use of a distribution manifold. A single manifold can accommodate multiple print engines or only one engine. In particular, the use of the print engines shown in Figures 3A to 3D is independent of the arrangements and configurations described herein with respect to the movement of the substrate. That is, the print bar and print head configurations shown in Figures 3A to 3D can be used in any of the embodiments disclosed herein with appropriate modifications, such as orienting the print bar to print upward or downward depending on the orientation of the substrate. In some embodiments, the print engine may include design features for managing the thermal load from the hot print die, such as the heat shield arrangement shown in Figure 3D, which is tightly integrated with the print head and can completely isolate the surroundings from the hot print head during operation.

[0086] Embodiments disclosed herein may use one or more print bars, each of which may include one or more print heads. As previously disclosed, in embodiments using multiple print bars, the print bars may be arranged in a linear configuration, for example, as shown in Figure 3E, or staggered, as shown in Figure 3F. Each of these figures shows a typical print bar 350, 360, each including three print heads 351, 352, 353, and 365, 366, 367 as seen from the perspective of the OVJP system's substrate. For example, print dies may have exclusion areas at the ends of each die that are not used for the print aperture, which are used to process the die and mount it to the print engine. If such adjacent dies are directly adjacent to each other, there may be no aperture where the dies touch each other. In this case, a staggered arrangement may be preferred to accommodate these areas. Generally, both staggered and linear arrangements can be used to print selected areas, such as display panels or regions, in one or more passes. However, staggered arrangements are typically simpler and more efficient to assemble on the print bar than linear arrangements without end exclusion areas. Staggered arrangements also allow for the deposition of material over relatively large areas, such as producing display panels of 55 inches or larger with fewer passes of the panel substrate through the system, by using redundant parallel bars that deposit material in the same area of ​​the substrate, and allow for thicker deposition with fewer scans of the substrate below the print head. When using a staggered arrangement as shown in Figure 3F, print heads at adjacent ends of the print bar may overlap with print heads on other bars, such as print heads 353 and 365 in Figure 3F.

[0087] Figures 4A and 4B show a top and side view, respectively, of an exemplary OVJP deposition system according to an embodiment disclosed herein. A pressure vacuum (PV) float table 405, sometimes referred to herein and in the art as a “PV table” or “float table,” supports a glass substrate on its inactive underside. The float table provides a vacuum / air cushion using, for example, nitrogen or another suitable gas, and may include one or more grippers 420 positioned around one or more sides, preferably all four sides, of the PV table. In this embodiment and other embodiments, the substrate does not physically contact anything other than the substrate grippers having the smallest contact area, so the possibility of frictional electrostatic charge accumulation is minimized. The entire PV table 405, as a single assembly or subsystem, can move along the main y-direction of movement 401 through the system from the input side (shown on the left side of Figure 4A) together with the substrate, passing through the print bar 412 to complete printing. As disclosed herein, each print bar may include one or more print heads. For example, the system may include three print bars, each configured to print a primary color to produce a full-color display on a substrate, but the embodiments disclosed herein are not limited to a specific number of print bars or a particular arrangement of colors, chemistry, or other arrangements of layers and / or materials. In this example, the active side of the substrate faces upward, the print bars are positioned above the substrate, and printing is performed downward on the active side of the substrate. That is, the print bars are configured and positioned to move downward in the direction of gravity until the material ejected from the print head collides with the substrate surface facing the print bars.

[0088] Figure 4C shows top, side, and front views of a substrate PV table 405, which can itself be held on a PV table support base 402. The PV table 405 may include features to maintain the system in a horizontal and stable position, such as mounting features that can function as precise leveling, latches, or other connectors to secure the table to the support base 402 or the like. The table 405 may include multiple vacuum gripper pairs or subsystems 420p, 420n for use in longitudinal or transverse substrate arrangements for holding substrates. Specifically, the substrate grippers 420 may allow adjustment of the substrate position by movement of at least 2°, preferably 3°. For example, the substrate grippers may allow movement of the substrate in the x, z, and / or θ directions. In this specification, the "x" direction means an axis in the plane of the substrate perpendicular to the direction of movement of the substrate through the deposition system 401, the "z" direction means a direction perpendicular and orthogonal to the plane of the substrate toward / away from the print bar, and "θ" means angle / rotation adjustment of the substrate about the z axis, i.e., rotation in the plane of the substrate. Such movement can be achieved in any embodiment disclosed herein that uses such grippers and / or enables movement of the substrate and / or any substrate support structure such as the illustrated substrate float table 405. This adjustment function enables alignment of the backplane on the substrate with the print bar and provides a mechanism to maintain accurate alignment even as the substrate moves within the system.

[0089] The deposition system may also include one or more control devices that provide user control and / or automatic control of the substrate grippers. For example, the control devices may include human interface components and / or electronic interfaces that allow adjustment of each angle of motion available to the grippers. The grippers 420 may include devices with minimal physical contact for holding and positioning the substrate, such as vacuum grippers or other pressure-based grippers that hold only one or more edges and / or back sides of the substrate. Thus, the gripper control device may include a pressure-volume (PV) control device. The substrate grippers disclosed herein can also be used to maintain the substrate in a planar configuration, for example, by counteracting gravity acting on the substrate (otherwise the substrate may flex). Specifically, one or more substrate grippers can hold the edges and / or inactive sides of the back side of the substrate to maintain the substrate in a planar configuration while it is being processed by the system. This feature may be particularly desirable in embodiments in which the print bar prints upward, i.e., against gravity.

[0090] The substrate PV table 405 may include one or more lift pins 427 that can be used to first position the substrate 110 on the PV table before retracting it, and then suspend and hold the substrate 110 in place by a gas cushion provided by the PV table. The lift pins or equivalent components can be used to position the substrate, for example, using the minimum contact surface area with the substrate. Alternatively, the lift pins may include channels that allow pressurized gas to pass through the pins, thereby levitating the substrate on the lift pins. In some embodiments disclosed herein using a PV float table or equivalent structure, the substrate is movable on the PV table independently of the movement of the PV table itself through the deposition system. That is, the float table may be movable within the system, for example, from input lock to output lock, along a path that moves the PV table and the substrate downwards from the print bar. At the same time, the position of the substrate on the PV table can be adjusted as disclosed herein, regardless of the position and / or movement of the PV table. Such an arrangement can allow for relatively large movements of the substrate using a PV table, while simultaneously allowing for fine adjustments of the substrate relative to the print bar on the PV table, independently of the movement of the PV table (for example, using a substrate gripper as disclosed herein). Alternatively, the substrate may be held in a fixed position relative to the PV table by a gripper as it moves along the PV table through the deposition system. In some embodiments, the movement and positioning of the substrate gripper can be controlled at least partially by a PV float table or synchronized with the movement of the table. For example, the substrate gripper may be able to operate in a zero-gravity environment while following a substrate floating in the z-direction on the PV table, such as via a gripper control device disclosed herein.

[0091] The float table may include a gas containment system to prevent gas leakage from the OVJP print bar from reaching the substrate edge. For example, a gas curtain and / or exhaust channel may be positioned around the substrate edge via channels within the float table to discharge overflow gas from the substrate and the float table.

[0092] In some embodiments, the print bar can also be immersed in a PV table such as 406 shown in Figure 4E, which can be controlled simultaneously or separately with respect to the substrate PV table 405. The print bar PV table can act as a bearing as shown in Figure 4E, which further helps to flatten the substrate, as well as the operation of the substrate PV table and / or gripper disclosed herein. In some embodiments, the movement of the substrate PV table and print bar assembly (whether immersed in the PV table or not) is arranged to achieve the specific relative physical arrangements disclosed herein. The position of the print bar and / or individual print engines on each print bar may be adjustable with respect to the physical frame holding the print bar and / or with respect to the substrate processed by the system. For example, the height of the print bar above the substrate may be adjustable. When multiple print bars are used, their heights can be adjusted independently or simultaneously so that their respective heights can be adjusted without affecting the height of other print bars. The print bar 412 and / or PV table 405 may also be rotatable in a plane parallel to the substrate, for example, to enable printing in "portrait" or "landscape" mode without rotating the substrate.

[0093] The on-site printhead alignment, measurement, and inspection subsystem 409 can be used as previously disclosed, as shown in the “parked” configuration in Figure 4A. During operation, subsystem 409 can move along the main y-direction 401, as can the substrate PV table 405.

[0094] As previously disclosed, a substrate placed on the PV table 405 can be aligned with the print bar 412 using one or more aligners, such as a visual camera, IR camera, barcode reader, or similar sensor 415. For example, the PV table 405 or the substrate itself may include various physical or electronic markers that can be positioned in known arrangements relative to the print bar 412 or the print bar support table 406. The aligner sensor 415 may be placed on a physical frame common to the print bar 412, for example, to ensure that the movement of the print bar 412 is adjusted by the aligner 415. Alternatively, the sensor 415 may be separated from the print subsystem and placed outside the deposition chamber. For example, some types of aligner sensors may not be compatible with the high vacuum environment inside the deposition chamber. Regardless of positioning, the sensor 415 can provide a signal that adjusts the relative position of the substrate and the print bar to maintain the appropriate alignment disclosed herein. As another example, while the aligner sensor may be vacuum-compatible, it may be located outside the deposition chamber for other reasons such as ease of user access or preferred installation.

[0095] Figure 4D shows a front view of the OVJP system of Figures 4A-4C, arranged within a vacuum chamber. The vacuum chamber 450 can be constructed such that each part is sealed to the others in order to maintain a low-pressure internal environment. For example, the lid 451 can be sealed to the body via an O-ring 452 or a similar mechanism. The OVJP system support column 470 can pass through the vacuum chamber 450, and the associated opening in the vacuum chamber base is sealed by a pass-through sealing bellows 472. An external isolator 477 keeps the OVJP system 499 physically isolated from the surrounding environment and / or vibrations and other movements of the vacuum chamber itself. More generally, these features allow the deposition system 499, which may be the system shown in Figures 4A-4C or any other embodiment disclosed herein, to be isolated from the base and walls of the vacuum chamber 450, so that chamber movement does not affect the processing of devices by the deposition system.

[0096] In some embodiments, opposing bearings can be used to equalize variations in substrate thickness, as shown, for example, in Figure 4E. Compared to other embodiments disclosed herein, the entire motion can be performed by the moving substrate PV table 405, so the substrate does not undergo large motions or accelerations. A gripper 420 positioned parallel to the direction of movement of the substrate PV table 405 can be used to make fine adjustments to correct repeatable motion errors of the moving PV table 405.

[0097] As with other embodiments disclosed herein, the substrate can be rotated by 90 degrees from and to “portrait” and “landscape” modes or any other desired direction, depending on the alignment of the long side of the substrate with respect to the print bar, for example, using a substrate gripper. Alternatively, the entire table can be rotated between directions. This may be preferable in some configurations because incomplete covering of the PV table can affect the levitation characteristics of the substrate.

[0098] In some embodiments, the substrate PV table 405 can also be used to cool the substrate, for example, via passive and / or active cooling techniques. As disclosed herein, such rotation can be performed independently of other movements or positioning of the PV float table. For example, a gripper used to position the substrate on the PV table can rotate the substrate to any desired position, regardless of the table's position and / or while the table is moving along the system's principal y-axis.

[0099] The embodiments shown in Figures 4A to 4E and other embodiments disclosed herein also have no infeed or outfeed air tables, thus reducing the consumption of float table gas. For example, unlike other embodiments disclosed herein, the substrate covers the float table at all times during the printing process, minimizing the consumption of operating float table gas (e.g., nitrogen). In other embodiments using an infeed and / or outfeed float table system architecture, the substrate typically moves along the infeed and outfeed tables, over them. Therefore, the tables may require significantly more gas consumption as they are partially covered by glass during movement. An example of such an arrangement is shown in Figure 6. This example uses a long, fixed float table with infeed / outfeed areas rather than a float table on a moving stage. The embodiments in Figures 4A to 4E also have relatively dewy moving parts above the substrate, further reducing the possibility of particle contamination during the printing process.

[0100] Figures 5A and 5B show side and front views, respectively, of the substrate and print bar in a vertically inverted configuration compared to those shown in 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 during movement. However, the substrate enters the system with the active side facing downwards, and the print bar is positioned below the substrate relative to gravity, although for clarity in the process description, the substrate is typically described as being positioned "below" the print bar. This is because the material is still ejected from the OVJP printhead toward the substrate in the opposite direction to gravity. The gantry is located above the substrate. The risk of the substrate unintentionally moving downward toward the print bar can be managed using PV chucks that secure the substrate. Similar PV systems can be used in other embodiments disclosed herein, such as the embodiment shown in Figure 8, or more generally, in any embodiment where it is desirable for the substrate to be positioned above the OVJP print bar relative to gravity.

[0101] Figures 6 to 9 show alternative embodiments that include some or all of the features described above with respect to Figures 4 and 5.

[0102] Figure 6, similar to Figures 5A and 5B, shows top, front, and side views of an embodiment in which the substrate 110 enters the system from the load lock with its active side (i.e., the side where the organic layer and other OLED layers are deposited and emit light after fabrication) facing downwards. In this embodiment, unlike the smaller PV table in Figures 4 and 5 which moves through the system with the substrate, the substrate moves on a PV table that extends through the system. The area of ​​the PV table on which the material is printed onto the substrate provides precise control of the separation between the print bar and the substrate, as previously disclosed. Similar to the arrangements in Figures 4 and 5, the substrate is supported by lift pin air pads for alignment so as not to physically contact other surfaces, reducing or eliminating the accumulation of ESD voltage due to friction. In this arrangement, the lift pins can contact the back (inactive) side of the substrate. In contrast, in the arrangement of Figure 5, the lift pins contact the active side of the substrate during loading or unloading, which is undesirable. Using lift pins with air pads, the substrate can be levitated on an air cushion provided by the air pads during loading, unloading, or alignment of the substrate within the system. The substrate can be held and moved by one or more previously disclosed grippers that contact the substrate on the inactive underside. The substrate moves on the PV air table from the infeed zone through the area below the print bar to the air table in the outfeed zone, with the active side always relative to the air table. The substrate can be positioned more accurately using previously disclosed automatic or semi-automatic alignment, such as via the use of a camera or other aligner.

[0103] The print bar is located below the surface of the substrate, printing upward toward the active side of the substrate and extending in a direction perpendicular to the main movement of the substrate. The print bar can be immersed in a dedicated PV air table such that the active side of the substrate is directly referenced to the print bar's PV air table. This allows for precise control of the vertical fly height gap between the substrate and the lower print bar, independent of variations in substrate thickness. Because the substrate and movable gripper are relatively lightweight, the movement of the substrate during the printing process can be precisely and dynamically controlled. A similar print bar PV table arrangement can be used in any other embodiment disclosed herein to allow for further control of the vertical distance between the substrate and the print bar.

[0104] Figure 7 shows a similar configuration to that in Figure 6, but the substrate enters the system from the load lock with its active side facing upward. Except for the relative position of the substrate and the print bar, the configuration in Figure 7 is identical or essentially identical to that in Figure 6. The substrate is supported on a lift pin air pad for alignment, and the substrate can be kept in motion by one or more grippers that contact the substrate on its inactive back surface without physically contacting any other surface. The substrate moves on the air table from the infeed zone through the area below the print bar to the air table in the outfeed zone. The print bar is above the surface of the substrate, printing downward toward the active side of the substrate and spreading in a direction perpendicular to the main movement of the substrate. The print bar can also be immersed in a dedicated PV air table, as previously disclosed, which can be configured to provide precise control of the vertical fly height gap between the substrate and the print bar above. Because the substrate and movable grippers are relatively lightweight, the movement of the substrate during the printing process can be controlled precisely and dynamically.

[0105] Figure 8 shows an arrangement in which the substrate enters the system with the active side facing downwards, as in Figure 6. In this arrangement, the inactive back side of the substrate is held by the upper PV table, unlike the active front side of the substrate which is supported by the lower PV table shown in Figure 6. The substrate can be supported on the previously disclosed lift-pin air pads for alignment to reduce or eliminate the accumulation of ESD voltage due to friction. The air tables in the infeed and outfeed regions are relative to the inactive back side of the substrate. The print bar is positioned below the substrate with respect to the direction of gravity in the print zone, and the substrate is held from above as it passes over the print bar. As a result, such embodiments can benefit from more precise motion and PV control, preventing part of the substrate from bending due to gravity or moving the entire substrate. The print bar prints upward toward the active side of the substrate and spreads in a direction perpendicular to the main movement of the substrate. Similar to the arrangement shown in Figure 6, the print bar itself is located in a dedicated PV air table, allowing for more precise control of the vertical fly height gap between the substrate and the lower print bar, independently of variations in substrate thickness. Because the substrate and movable gripper are relatively lightweight, the movement of the substrate during the printing process can be controlled precisely and dynamically.

[0106] Figure 9 shows a front view of an alternative configuration in which the substrate is not supported on an air table when entering the system, unlike the configurations shown in Figures 6 and 7. Instead, the substrate is vacuum-chucked to a large, very flat chuck surface with the active side facing downwards. The print bar is positioned below the substrate relative to gravity and prints upwards on the active surface of the substrate. The payload of the moving substrate is inevitably much heavier than in Figures 6 and 7, and this heavy object moves through the system. As a result, correcting dynamic motion errors in this configuration may require careful consideration.

[0107] Embodiments disclosed herein allow substrates to exit the system after being deposited via an OVJP print bar, either by means of an input load lock in which the substrate first enters the deposition system, or by means of a dedicated output load lock, thereby achieving "in-line" onward forward dispensation of substrates in a dedicated fabrication environment. The in-line configuration can utilize dedicated features of the vacuum chamber and system transport assumed to enable in-line motion. For example, referring to the configuration shown in Figure 6 and similar configurations, a dual-gripper option can be used in which a first dedicated gripper transports the substrate over the print bar onto an exit air table, then a second gripper transports the substrate to an exit load lock, and the primary gripper quickly returns to the input air table to receive a new substrate from the input load lock. Similar mechanisms can be used in any other system transport configuration disclosed herein, including any of those described with respect to Figures 4 to 9.

[0108] The embodiments disclosed herein may be operable within a certain range of internal pressures. The deposition chamber is sometimes referred to as a “vacuum chamber,” but the operating pressure inside the chamber during deposition by the OVJP deposition system is 100–300 Torr, or in some embodiments, up to 400 Torr. This is sufficient to levitate the substrate on the float table disclosed herein, but is a much higher pressure than conventional “vacuum” operating pressures.

[0109] Unless otherwise expressly stated, or unless impossible or impractical due to physical constraints, any feature disclosed herein in relation to one or more embodiments may be used in conjunction with any other embodiments disclosed and / or claimed herein. As a non-limiting example, any embodiment using a substrate gripper disclosed herein may include edge and / or back surface substrate grippers of any configuration and arrangement disclosed or shown in relation to any of the embodiments disclosed herein. As another non-limiting example, any embodiment disclosed herein may allow rotation of the substrate in the xy plane during processing of the substrate in a deposition system.

[0110] In addition to the arrangements described herein in which the substrate moves through the region below the print bar, in some embodiments the substrate can be kept stationary relative to the deposition chamber while the print bar structure moves above it. More generally, although described herein as the movement of the substrate, equivalent movement can be achieved by the relative movement of the substrate and / or the print bar structure. For example, the float table and one or more grippers disclosed herein can be used to keep the substrate stationary in the deposition system while minimizing physical contact with the substrate. One or more print engines, print bars, print heads, or any preferred combination thereof can then move across the region above the substrate while the material is ejected from the print head and deposited onto the substrate.

[0111] For the sake of clarity, the disclosures and indications relating to jet printing of organic materials are made herein by reference, but embodiments disclosed herein may be used to deposit other materials and / or modify deposition techniques. For example, non-organic materials, biomaterials, or other materials that are compatible or intrinsically compatible with common process parameters known to be suitable for organic materials or known modifications thereof may be used.

[0112] For example, lines of condensable material can be deposited on glass or similar substrates such as architectural glass using any embodiment disclosed herein. Such lines can be used to absorb IR radiation, provide electrical leads to embedded electronic components, or impart other properties to the glass as a whole. Such lines are relatively thin, for example, 25, 50, or 100 μm, meaning they can be printed on glass without significantly affecting the apparent transparency of the glass. For example, when fine lines of IR absorber are printed on glass, the resulting glass may be suitable for use in office buildings and similar locations where a large amount of visible light enters the building and it is desirable to block a large amount of infrared radiation. The embodiments disclosed herein are particularly suited to such applications, unlike conventional deposition systems, especially jet-based systems, and may not be as suitable for operations and deposition on relatively large substrates disclosed herein.

[0113] The various embodiments described herein are merely examples and are not intended to limit the scope of the invention. For example, many of the materials and structures described herein can be replaced with other materials and structures without departing from the spirit of the invention. Accordingly, the claimed invention may include variations from the specific examples and preferred embodiments described herein, as will be apparent to those skilled in the art. The various theories of why the invention works are not intended to limit it. [Prior art documents] [Patent Documents]

[0114] [Patent Document 1] U.S. Patent No. 5,844,363 [Patent Document 2] U.S. Patent No. 6,303,238 [Patent Document 3] U.S. Patent No. 5,707,745 [Patent Document 4] U.S. Patent No. 7,279,704

Claims

1. An organic vapor jet printing (OVJP) deposition system, One or more OVJP print bars and; Float table and; Includes one or more sensors, Each of the one or more OVJP print bars includes one or more OVJP print dies. The aforementioned float table is One or more substrate grippers are configured to hold a substrate having a first active surface and to adjust the position of the substrate on the float table with a movement of at least 2°. The system includes one or more control devices arranged to provide control to the one or more substrate grippers, The one or more sensors are configured to measure the alignment of the substrate on the float table with the one or more OVJP print bars. The float table is movable in the region extending below the one or more OVJP print bars. The float table and one or more of the OVJP print bars are rotatable relative to each other. The OVJP deposition system is characterized in that the substrate is movable on the float table independently of the movement of the float table below the one or more OVJP print bars.

2. The OVJP deposition system according to claim 1, further comprising a height control subsystem, wherein the height control subsystem is configured to control the relative distance between the one or more OVJP print bars above the float table.

3. The OVJP deposition system according to claim 1, wherein the float table includes a pressure-volume (PV) float table.

4. The OVJP deposition system according to claim 1, wherein the movement of the one or more substrate grippers is controlled by the float table such that the movement of the one or more substrate grippers is at least partially determined by the movement of the float table.

5. The OVJP deposition system according to claim 1, wherein the one or more sensors include an alignment camera, and the alignment camera is configured to align the substrate with the one or more OVJP print bars.

6. The OVJP deposition system according to claim 1, wherein the one or more OVJP print bars include a plurality of OVJP print bars, and at least one of the plurality of OVJP print bars overlaps with at least one other of the plurality of OVJP print bars printing on the same area of ​​the substrate.

7. The OVJP deposition system according to claim 1, wherein the substrate does not come into contact with any physical surface other than the one or more substrate grippers during processing by the OVJP deposition system.

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

9. A method for operating the OVJP sedimentation system, To obtain a circuit board; The substrate is placed on a float table, and the position of the substrate is fixed using one or more grippers; The position of the substrate on the float table is adjusted via the one or more grippers; Moving the float table and the substrate to a position in the OVJP deposition system where the substrate is positioned below the print bar of the OVJP deposition system; The float table and the print bar rotate relative to each other or both such that the print bar is positioned perpendicular or parallel to the substrate, or at any desired angle with respect to the direction of movement of the substrate; Discharging the deposition material from the print bar onto the substrate; A method characterized by moving the float table to a position in the OVJP deposition system where the substrate is not below the print bar of the OVJP deposition system.

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