Photonic devices for sintering and drying metal electrodes

Abstract

A system for photonic sintering of a metal electrode is provided. The system comprises a display. The display includes a substrate comprising a first side and a second side, and the display includes the metal electrode that extends from the first side to the second side. The system also includes a photonic device for sintering the metal electrode. The photonic device comprises a lamp configured to generate photonic energy, and the photonic device comprises a mask positioned between the metal electrode and the lamp. The mask defines a slot therein, and the mask is configured to allow a portion of the photonic energy from the lamp to pass through the slot towards the metal electrode.

Description

PHOTONIC DEVICES FOR SINTERING AND DRYING METAL ELECTRODESCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application Serial No. 63 / 535373 filed on August 30, 2023, the content of which is relied upon and incorporated herein by reference in its entirety.FIELD

[0002] Embodiments relate generally to approaches for photonically sintering or drying and printing or repairing metal electrodes for displays.BACKGROUND

[0003] Top emission micro light emitting diode (micro LED) displays require a method to electrically interconnect the light emitting diodes (LEDs) on the top surface of a substrate with a driver controller board located on the bottom surface of the substrate. Typically, this is accomplished by use of a flex connector attached at the substrate edge. In the case of a borderless, bezel free, or tiled display, it is not desirable to use a flex connector attached to the substrate top surface. The flex connector in this case is either visible to the viewer and then needs to be hidden by a bezel or the flex connector occupies too much space between tiles and prohibits seamless tiling. In both cases, the typical flex connector is too big to meet the requirements.

[0004] Wrap-around metal electrodes offer a solution for electrically connecting components on the top surface of a display substrate with electrical components on the bottom surface of a display substrate. Wrap-around metal electrodes are fabricated around an edge of a display substrate to connect the electrical components on different sides of the display substrate. Wrap-around metal electrodes have been demonstrated with borderless, bezel free, and tiled displays. These metal electrodes include various materials (gold, silver, copper, titanium, indium tin oxide, molybdenum, aluminum, etc.) and have been fabricated using fabrication methods including printing, vacuum deposition, patterning, pad printing, and electroplating. Historically, batch processing methods are performed where all of the metal electrodes on a single micro LED tile are deposited at one time. While this is advantageous in some respects for a manufacturing process, if the yield during deposition is not 100 percent or if some of the metal electrodes are damaged downstream by handling or other processing steps, then these batch processing methods cannot be easily implemented to repair individual metal electrodes on the edge or the face of the tile.BRIEF SUMMARY

[0005] Methods to improve wrap-around metal electrode electrical performance are subject to strict processing limitations as a result of the sensitive nature of the microelectronics (e.g., thin-film transistors, etc.) and other display components present on the substrates. These processing limitations include limitations regarding the temperature exposure over time, material exposure, etc. As the methods for depositing the wrap-around metal electrodes have evolved, so have the limitations for processing of the micro LED tiles, and this has resulted in limited process windows for further improvements.

[0006] Metal electrode printing is performed by depositing metal inks onto a tiled substrate in a pre-determined pattern. Metal inks include particle based inks, reactive inks, blends of particle based inks and reactive inks, and multi-layer inks. In metal electrode printing, metal inks have historically been sintered at elevated temperatures ranging from 100 degrees Celsius to 250 degrees Celsius to sinter metal particles so that an electrically conductive path is formed. Metal electrode printing provides a low-cost three-dimensional solution in comparison to incumbent sputtering technologies due to high thickness and three-dimensional patterning required for wrap-around metal electrodes.

[0007] In an example printing process, ink is delivered to a nozzle which directs the ink onto the substrate. The deposited ink is then dried and consolidated at temperatures between about 100 degrees Celsius to about 250 degrees Celsius. The substrate is then coated with a protective polymer coating which provides mechanical protection for metal electrodes and provides the optical properties to enable an invisible tiled edge. The electrical resistivity of the metal electrodes can be as low as 2.5 times the bulk material resistivity, and the electrical resistivity may depend on a size of the nanoparticles used, the consolidation condition, and the organic composition of the ink. As a general rule, the longer or hotter the sintering conditions are, the better electrical line resistivities achieved. To obtain silver wrap-around electrodes having desirable line resistivities through thermal sintering, the electrodes typically must be thermally sintered at temperatures greater than 150 degrees Celsius. However, this may be problematic where assemblies have other sensitive components that may be damaged at these elevated temperatures or where properties of other components such as the substrate may be impacted by the elevated temperatures. Various embodiments described herein generally relate to wrap-around metal electrodes for displays such as micro LED displays and other applications, and the displays may be borderless, bezel free, or tiled displays. Wrap-around metal electrodes may be formed using various printing technologies. These technologies include aerosol jetting, ink jetting, spray coating, etc. Preparation involves singulatingcomponents such as display tiles, sizing and shaping of display tiles, edge preparation, metal electrode printing, and the application of a protective coating. Various printing technologies described herein may be configured to print or repair individual metal electrodes, making the printing technologies beneficial for use in repairing damaged metal electrodes. By repairing these damaged metal electrodes, open circuits may be avoided, and the high resistance of electrical lines may be avoided as well in some embodiments. The ability to print individual metal electrodes may drastically improve yield, resulting in significant cost savings and reduced defects in displays.

[0008] Various embodiments discussed herein provide a localized alternative method for sintering metal electrodes using the photonic energy of light rather than thermal energy. Photonic energy may be used to generate metal electrodes with a low resistivity to meet customer specifics for electrical performance without damaging a micro LED tile. The exposure area of the tile may be limited to specific regions where metal electrodes exist to generally keep the substrate at a temperature of less than 100 degrees Celsius. Limiting the exposure area may also limit photonic exposure to sensitive components of the micro LED display that may otherwise be damaged.

[0009] Photonic devices may be used for photonically sintering metal electrodes. Photonic sintering may result in improved connectivity of nanoparticles in metal electrodes relative to other thermally sintered metal electrodes. Additionally, photonic sintering may result in improved electrical performance compared to low temperature thermal sintering. Photonic sintering may also be used to accomplish electrical performance comparable to thermal sintering, with photonic sintering being completed significantly faster than photonic sintering. For example, photonic sintering may take only five minutes while thermal sintering may take twenty minutes or more.

[0010] Various embodiments relate to photonic sintering and drying of metal electrodes such as metal inks, with these metal electrodes printed, for example, as a wrap-around metal electrode on a substrate. Metal electrodes may be printed with a high optical density, so photonic sintering and drying of these high optical density metal electrodes may result in light being directed towards the metal electrodes rather than other components with low optical densities (e.g., the substrate). Photonic devices may comprise a mask and a lamp. When the photonic device is actively being used, the mask may be positioned between the lamp and a substrate with a metal electrode provided thereon. Additionally, the mask defines a slot between the lamp source and substrate, and the slot may allow the light from the photonicdevice to pass through to the metal electrode while the remainder of the mask may prevent exposure to other portions of the substrate and other components thereon. In some embodiments, the relative angle and / or positioning of the photonic device relative to the substrate may be adjusted after one or more exposures to evenly sinter or dry a metal electrode. Photonic devices may sinter metal electrodes so that the metal electrodes have a low line resistivity and a low contact resistance, and photonic devices may accomplish this while limiting the amount of heating for bulk substrates and also while limiting direct photonic exposure to sensitive components. For example, direct photonic exposure to sensitive components like thin film transistors and other components having a high optical density may be avoided.

[0011] Additionally, embodiments described herein limit the exposure area to specific regions so as to not damage any components of an assembly with the photonic energy of the light. Portions of assemblies may be populated with other high optical density components and other photosensitive materials that may be damaged by photonic exposure. The slot of photonic devices may allow light to be directed to a limited exposure area, and the mask may prevent light from extending to other regions with high optical density components or other photosensitive components. The slot may focus light on a specific location and minimize the amount of light emitted towards other locations, making the photonic devices more energy efficient.

[0012] Various embodiments also relate to photonic drying of metal electrodes to remove solvents and / or other volatile components from metal electrodes. Drying may result in improved adhesion between a metal electrode and a substrate, and drying may also improve line resistivity, contact resistance, and other electrical properties of metal electrodes. Photonic devices are also contemplated for use in photonic drying. Unlike thermal drying, which exposes an entire assembly to an elevated temperature and increases the risk of possible thermal induced degradation, photonic drying is configured to provide more localized drying of metal electrodes to avoid unintended exposure of components to photonic drying. Photonic drying is also configured to maintain a substrate underneath a threshold temperature during photonic drying to maintain certain properties for the substrate. Photonic drying also is faster than thermal processing and is configured to accomplish resistivity values comparable to those accomplished using thermal drying. Photonic drying may also be more energy efficient than thermal drying. The same photonic devices may be used for both photonic drying and photonic sintering in some embodiments, and this may make manufacturing processes more efficient,less complex, and more cost-effective as other components required for thermal drying or thermal sintering may be omitted.

[0013] In an example embodiment, a system for photonic sintering of a metal electrode is provided. The system comprises a display. The display includes a substrate comprising a first side and a second side, and the display includes the metal electrode that extends from the first side to the second side. The system also includes a photonic device for sintering the metal electrode. The photonic device comprises a lamp configured to generate photonic energy, and the photonic device comprises a mask positioned between the metal electrode and the lamp. The mask defines a slot therein, and the mask is configured to allow a portion of the photonic energy from the lamp to pass through the slot towards the metal electrode.

[0014] In some embodiments, the display may include a component having a high optical density, and the mask may be configured to prevent the photonic energy from the lamp from extending towards the component. Additionally, in some embodiments, the component may be a thin film transistor.

[0015] In some embodiments, the system may also include a second photonic device for sintering the metal electrode. The second photonic device may include a second lamp configured to generate photonic energy and a second mask defining a second slot therein. The second mask may be configured to allow a portion of the photonic energy from the second lamp to pass through the second slot. Additionally, the photonic device and the second photonic device may target different locations on the metal electrode. Furthermore, in some embodiments, the photonic device and the second photonic device may be positioned in different orientations relative to the substrate.

[0016] In some embodiments, the metal electrode may extend from the first side around at least one edge to the second side. In some embodiments, the slot may define a width that is approximately equal to a width of the metal electrode. In some embodiments, at least one of the metal electrode or the photonic device may be configured to be repositioned relative to the other. In some embodiments, the photonic device may also comprise at least one of an optical lens or a mirror, and the optical lens or the mirror may be configured to be adjusted to alter properties of photonic energy generated by the photonic device. In some embodiments, a temperature at the substrate may remain below about 100 degrees Celsius when the photonic device is activated. In some embodiments, the photonic device may be configured to photonically dry a target material in less time than a thermal drying device, or the photonicdevice may be configured to photonically sinter a target material in less time than a thermal sintering device.

[0017] In some embodiments, the photonic device may be configured to generate a first set of one or more pulses of photonic energy towards the metal electrode, and the photonic device may be configured to subsequently generate a second set of one or more pulses of photonic energy towards the metal electrode. The second set of one or more pulses of photonic energy may have an increased intensity relative to the first set of one or more pulses of photonic energy. Additionally, in some embodiments, the second set of one or more pulses may have at least one of a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses, a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses, a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses, a second voltage level that is different relative to a first voltage level applied for the first set of one or more pulses, or a second power level that is different relative to a first power level applied for the first set of one or more pulses.

[0018] In another example embodiment, a sintering device for sintering a metal electrode is provided. The sintering device comprises a lamp configured to generate photonic energy and a mask defining a slot therein. The mask is configured to allow a portion of the photonic energy from the lamp to pass through the slot towards the metal electrode to sinter the metal electrode.

[0019] In some embodiments, the metal electrode may be on an assembly comprising the metal electrode and a substrate, and the substrate may have a lower optical density relative to the metal electrode. Furthermore, in some embodiments, the mask may be configured to shield other components having an optical density that is higher than the optical density of the substrate from the photonic energy. Additionally, in some embodiments, the substrate may be exposed to a maximum temperature of less than about 100 degrees Celsius in some embodiments. In some embodiments, the metal electrode may be a wrap-around metal electrode that extends from a first side of the substrate to a second side of the substrate. In some embodiments, the assembly may be part of a display, and the display may be at least one of a borderless display, a bezel free display, or a tiled display. Furthermore, in some embodiments, the slot may define a circular shape, an oval shape, a rounded shape, a rectangular shape, a triangular shape, a polygonal shape, or an asymmetrical shape. Additionally, in some embodiments, the slot may have a cross-sectional area between about 1 square centimeter to about 10 square centimeters.

[0020] In another example embodiment, a method for using a sintering device is provided. The method comprises providing a substrate comprising a first side and a second side, positioning a metal electrode so that the metal electrode extends from the first side to the second side, and providing a sintering device. The sintering devices comprises a lamp configured to generate photonic energy, and the sintering device also comprises a mask defining a slot therein, with the mask being configured to allow a portion of the photonic energy from the lamp to pass through the slot. The method also includes positioning the sintering device relative to the metal electrode so that the slot is positioned relative to the metal electrode and activating the sintering device to generate the photonic energy. In some embodiments, the positioning of the metal electrode may be performed using aerosol jetting, ink-jetting, or spray coating.

[0021] In another example embodiment, a display is provided that is made by a process. The process comprises providing a substrate comprising a first side and a second side, positioning a metal electrode so that the metal electrode extends from the first side to the second side, and providing a sintering device. The sintering device comprises a lamp configured to generate photonic energy, and the sintering device also comprises a mask defining a slot therein. The mask is configured to allow a portion of the photonic energy from the lamp to pass through the slot. The process also includes positioning the sintering device relative to the metal electrode so that the slot is positioned relative to the metal electrode and activating the sintering device to generate the photonic energy.

[0022] In another example embodiment, a photonic sintering device for photonically sintering a metal electrode is provided. The photonic sintering device comprises a lamp configured to generate photonic energy. The photonic sintering device is configured to sinter the metal electrode by generating a first set of one or more pulses of photonic energy towards the metal electrode and a second set of one or more pulses of photonic energy towards the metal electrode. The second set of one or more pulses is generated after the first set of one or more pulses. The second set of one or more pulses has at least one of a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses, a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses, a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses, a second voltage level that is different relative to a first voltage level applied for the first set of one or more pulses, or a second power level that is different relative to a first power level applied for the first set of one or more pulses.

[0023] In some embodiments, the second number of pulses is increased relative to the first number of pulses in the first set of one or more pulses, the second frequency of pulses is increased relative to the first frequency of pulses in the first set of one or more pulses, the second duration of pulses is increased relative to the first duration of pulses in the first set of one or more pulses, the second voltage level is increased relative to the first voltage level applied for the first set of one or more pulses, or the second power level is increased relative to the first power level applied for the first set of one or more pulses.

[0024] In some embodiments, the metal electrode is a wrap-around metal electrode that extends from a first side of a substrate to a second side of the substrate. Additionally, in some embodiments, the metal electrode is part of a display, and the display is at least one of a borderless display, a bezel free display, or a tiled display.

[0025] In some embodiments, the metal electrode may comprise at least one of gold, silver, copper, titanium, indium tin oxide, molybdenum, or aluminum. In some embodiments, the metal electrode may comprise at least one of a particle based ink, a reactive ink, or a multilayer ink.

[0026] In another example embodiment, a method for sintering is provided. The method comprises causing a first set of one or more pulses to be generated and causing a second set of one or more pulses to be generated. The second set of one or more pulses is generated after the first set of one or more pulses. The second set of one or more pulses has at least one of a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses, a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses, a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses, a second voltage level that is different relative to a first voltage level applied for the first set of one or more pulses, or a second power level that is different relative to a first power level applied for the first set of one or more pulses.

[0027] In some embodiments, the second number of pulses may be increased relative to the first number of pulses in the first set of one or more pulses, the second frequency of pulses may be increased relative to the first frequency of pulses in the first set of one or more pulses, the second duration of pulses may be increased relative to the first duration of pulses in the first set of one or more pulses, the second voltage level may be increased relative to the first voltage level applied for the first set of one or more pulses, or the second power level may be increased relative to the first power level applied for the first set of one or more pulses.

[0028] In some embodiments, the method may be applied to a metal electrode in a display. Additionally, in some embodiments, the metal electrode may be a wrap-around metal electrode that extends from a first side of a substrate to a second side of the substrate. In some embodiments, the display may be at least one of a borderless display, a bezel free display, or a tiled display.

[0029] In some embodiments, the metal electrode may comprise at least one of gold, silver, copper, titanium, indium tin oxide, molybdenum, or aluminum. In some embodiments, the metal electrode may comprise at least one of a particle based ink, a reactive ink, or a multilayer ink. In some embodiments, the method may also comprise applying a protective coating around sintered material.

[0030] In another example embodiment, a sintering device for sintering a metal electrode is provided. The sintering device is configured to sinter the metal electrode by generating a first set of one or more pulses of energy and a second set of one or more pulses of energy towards the metal electrode. The second set of one or more pulses of energy are generated after the first set of one or more pulses of energy. Additionally, the second set of one or more pulses of energy has at least one of a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses of energy, a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses of energy, a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses of energy, a second voltage level that is different relative to a first voltage level applied for the first set of one or more pulses of energy, or a second power level that is different relative to a first power level applied for the first set of one or more pulses of energy.

[0031] In some embodiments, the second number of pulses may be increased relative to the first number of pulses in the first set of one or more pulses, the second frequency of pulses may be increased relative to the first frequency of pulses in the first set of one or more pulses, the second duration of pulses may be increased relative to the first duration of pulses in the first set of one or more pulses, the second voltage level may be increased relative to the first voltage level applied for the first set of one or more pulses, or the second power level may be increased relative to the first power level applied for the first set of one or more pulses.

[0032] In some embodiments, the sintering device may be a photonic sintering device that is configured to generate pulses of photonic energy. In some embodiments, the sintering device may be at least one of a thermal sintering device, a laser sintering device comprising a laser, or an infrared sintering device comprising an infrared lamp. In some embodiments, the metalelectrode may be a wrap-around metal electrode that extends from a first side of a substrate to a second side of the substrate. In some embodiments, the metal electrode may be a part of a display, and the display may be at least one of a borderless display, a bezel free display, or a tiled display. Furthermore, in some embodiments, the metal electrode may comprise a metal ink that includes at least one of gold, silver, copper, titanium, indium tin oxide, molybdenum, or aluminum.

[0033] In another example embodiment, a method for preparing a metal electrode is provided. The method comprises providing a substrate a first side and a second side, positioning a metal electrode so that the metal electrode extends from the first side to the second side, and providing a sintering device. The sintering device comprises a lamp configured to generate photonic energy. The sintering device also comprises a mask defining a slot therein, with the mask being configured to allow a portion of the photonic energy from the lamp to pass through the slot. The method also comprises positioning the sintering device relative to the metal electrode so that the slot is positioned relative to the metal electrode, causing a first set of one or more pulses to be generated, and causing a second set of one or more pulses to be generated after generation of the first set of one or more pulses. The second set of one or more pulses has at least one of a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses, a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses, a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses, a second voltage level that is different relative to a first voltage level applied for the first set of one or more pulses, or a second power level that is different relative to a first power level applied for the first set of one or more pulses.

[0034] In some embodiments, the second number of pulses may be increased relative to the first number of pulses in the first set of one or more pulses, the second frequency of pulses may be increased relative to the first frequency of pulses in the first set of one or more pulses, the second duration of pulses may be increased relative to the first duration of pulses in the first set of one or more pulses, the second voltage level may be increased relative to the first voltage level applied for the first set of one or more pulses, or the second power level may be increased relative to the first power level applied for the first set of one or more pulses.

[0035] In another example embodiment, a display is provided that is made by a process. The process comprises providing a substrate comprising a first side and a second side, positioning a metal electrode so that the metal electrode extends from the first side to the secondside, providing a sintering device, positioning the sintering device relative to the metal electrode so that a slot is positioned relative to the metal electrode, causing a first set of one or more pulses to be generated, and causing a second set of one or more pulses to be generated after generation of the first set of one or more pulses. The second set of one or more pulses has at least one of a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses, a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses, a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses, a second voltage level that is different relative to a first voltage level applied for the first set of one or more pulses, or a second power level that is different relative to a first power level applied for the first set of one or more pulses.

[0036] In some embodiments, the second number of pulses is increased relative to a first number of pulses in the first set of one or more pulses, the second frequency of pulses is increased relative to a first frequency of pulses in the first set of one or more pulses, the second duration of pulses is increased relative to a first duration of pulses in the first set of one or more pulses, the second voltage level is increased relative to a first voltage level applied for the first set of one or more pulses, or the second power level is increased relative to a first power level applied for the first set of one or more pulses.

[0037] In another example embodiment, a method for removal of a volatile component from a metal electrode is provided. The method comprises providing a substrate having the metal electrode positioned on the substrate, positioning a photonic device relative to the metal electrode, activating the photonic device to remove the volatile component from the metal electrode to form a dried metal electrode, and sintering the dried metal electrode.

[0038] In some embodiments, the volatile component may be at least one of a solvent or an amine based compound, water, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, glycerol, or decane. In some embodiments, a temperature at the substrate remains below about 100 degrees Celsius when the photonic device is in an activated state. In some embodiments, the photonic device may be configured to operate at about 2 hertz and at about 3 kilowatts per square centimeter. In some embodiments, the photonic device may be configured to remove the volatile component in less time than a thermal drying device.

[0039] In some embodiments, the photonic device may comprise a lamp configured to generate photonic energy. The photonic device may also comprise a mask defining a slottherein, and the mask may be configured to allow a portion of the photonic energy from the lamp to pass through the slot towards the metal electrode. Additionally, in some embodiments, the sintering of the dried metal electrode may be performed by performing various operations. These operations may include providing a photonic sintering device. The photonic sintering device may comprise a second lamp configured to generate second photonic energy, and the photonic sintering device may also comprise a second mask defining a second slot therein, with the second mask being configured to allow a portion of the second photonic energy from the second lamp to pass through the second slot towards the metal electrode. The operations may also include positioning the photonic sintering device relative to the metal electrode so that the second slot is positioned relative to the dried metal electrode. The operations may also include activating the photonic sintering device to generate the second photonic energy. Additionally, in some embodiments, a temperature at the substrate may remain below about 100 degrees Celsius when the photonic sintering device is in an activated state. Furthermore, in some embodiment, the photonic sintering device may be configured to operate at a frequency of about 0.5 hertz and at an optical power of about 5 kilowatts per square centimeter to about 8 kilowatts per square centimeter.

[0040] In some embodiments, the method may also comprise positioning the photonic device relative to the dried metal electrode so that the slot is positioned relative to the metal electrode and activating the photonic device to generate the photonic energy to photonically sinter the dried metal electrode. Also, in some embodiments, a temperature at the substrate may remain below about 100 degrees Celsius when the photonic device is being used to photonically sinter the dried metal electrode. Furthermore, in some embodiments, the photonic device may be configured to operate at a frequency of about 0.5 hertz and at an optical power of about 5 kilowatts per square centimeter to 8 kilowatts per square centimeter when being used to photonically sinter the dried metal electrode.

[0041] In some embodiments, the method may also include positioning a second photonic device relative to the metal electrode, and the method may also include activating the second photonic device to remove the volatile component from the metal electrode to form the dried metal electrode. The photonic device and the second photonic device may target different locations on the metal electrode. Additionally, in some embodiments, the photonic device and the second photonic device may be positioned in different orientations relative to the substrate.

[0042] In some embodiments, the method may also comprise repositioning at least one of the metal electrode or the photonic device relative to the other so that the photonic devicetargets a different portion of the metal electrode or so that the photonic device targets a location on the metal electrode at a different angle.

[0043] In another example embodiment, a photonic device for removal of a volatile component from a metal electrode is provided. The photonic device comprises a lamp configured to generate photonic energy. The photonic device also includes a mask defining a slot therein, with the mask being configured to allow a portion of the photonic energy from the lamp to pass through the slot towards the metal electrode to remove the volatile component from the metal electrode.

[0044] In some embodiments, the volatile component may be at least one of a solvent or an amine based compound, water, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, glycerol, or decane. In some embodiments, the metal electrode may be positioned on a substrate, and a temperature at the substrate may remain below about 100 degrees Celsius when the photonic device is in an activated state. In some embodiments, the photonic device may be configured to remove the volatile component in less time than a thermal drying device. In some embodiments, the photonic device may be configured to photonically sinter the metal electrode.

[0045] In another example embodiment, a method for preparing a metal electrode is provided. The method comprises providing a substrate comprising a first side and a second side, positioning the metal electrode so that the metal electrode extends from the first side to the second side, and providing a photonic device. The photonic device comprises a lamp configured to generate photonic energy. The photonic device also comprises a mask defining a slot therein, and the mask allows a portion of the photonic energy from the lamp to pass through the slot. The method also comprises positioning the photonic device relative to the metal electrode so that the slot is positioned relative to the metal electrode, and the method also comprises activating the photonic device to generate the photonic energy.

[0046] In some embodiments, the method may also comprise positioning a sintering device relative to the metal electrode, and the method may also comprise activating the sintering device to sinter the metal electrode. Furthermore, in some embodiments, the sintering device and the photonic device may be the same device.

[0047] In another example embodiment, a display is provided that is made by a process. The process comprises providing a substrate comprising a first side and a second side, positioning a metal electrode so that the metal electrode extends from the first side to the second side, and providing a photonic device. The photonic device comprises a lamp configured togenerate photonic energy. The photonic device also comprises a mask defining a slot therein, with the mask allowing a portion of the photonic energy from the lamp to pass through the slot. The process also comprises positioning the photonic device relative to the metal electrode so that the slot is positioned relative to the metal electrode, and the process also comprises activating the photonic device to generate the photonic energy. In some embodiments, the process used to make the display may further comprise positioning a sintering device relative to the metal electrode and activating the sintering device to sinter the metal electrode.

[0048] In another example embodiment, a method for preparing metal electrodes is provided. The method comprises identifying a location at a surface of a substrate, with the location comprising a position where an existing metal electrode is damaged. The method also comprises aerosol jet printing a repair metal electrode at the location and sintering the repair metal electrode.

[0049] In some embodiments, the method may also comprise pre-treating the surface of the substrate or the existing metal electrode prior to the aerosol jet printing of the repair metal electrode at the location. Additionally, in some embodiments, the pre-treating of the surface of the substrate may expose a buried layer to reduce a contact resistance for the repair metal electrode relative to a damaged metal electrode. Furthermore, in some embodiments, the pretreating of the existing metal electrode may remove an insulating oxide layer or debris from a damaged metal electrode.

[0050] In some embodiments, aerosol jet printing of the repair metal electrode at the location may be completed by aerosol jet printing only one repair metal electrode at a time. In some embodiments, the repair metal electrode may comprise at least one of a particle ink or a reactive ink.

[0051] In some embodiments, the method may also comprise drying the repair metal electrode to remove a volatile component from the repair metal electrode, and drying of the repair metal electrode may be performed before the sintering of the repair metal electrode. Furthermore, in some embodiments, the sintering of the repair metal electrode may comprise photonically sintering the repair metal electrode. Additionally, in some embodiments, the drying of the repair metal electrode comprises photonically drying the repair metal electrode. Also, in some embodiments, a temperature at the substrate may remain below about 100 degrees Celsius during photonic sintering and during photonic drying.

[0052] In another example embodiment, a system for preparing metal electrodes is provided. The system comprises a substrate comprising a first side and a second side, an aerosoljet printer for printing a repair metal electrode on the substrate, and a photonic device. The photonic device comprises a lamp configured to generate photonic energy. The photonic device also comprises a mask defining a slot therein, and the mask is configured to allow a portion of the photonic energy from the lamp to pass through the slot towards the metal electrode to photonically sinter the repair metal electrode.

[0053] In some embodiments, the aerosol jet printer may be used to print the repair metal electrode on the substrate to repair a damaged metal electrode. Additionally, in some embodiments, the aerosol jet printer may be configured to aerosol jet print one repair metal electrode at a time. In some embodiments, the repair metal electrode comprises at least one of a particle ink or a reactive ink.

[0054] In some embodiments, the photonic device may be configured to photonically dry the repair metal electrode to remove a volatile component from the repair metal electrode before photonically sintering the repair metal electrode. Additionally, in some embodiments, a temperature at the substrate may remain below about 100 degrees Celsius during photonic sintering and during photonic drying.

[0055] In some embodiments, the system may further comprise a second photonic device, and the second photonic device may be configured to photonically dry the repair metal electrode to remove a volatile component from the repair metal electrode before photonically sintering the repair metal electrode.

[0056] In another example embodiment, a display made by a process is provided. The display comprises identifying a location at a surface of a substrate comprising a position where an existing metal electrode is damaged, aerosol jet printing a repair metal electrode at the location, and sintering the repair metal electrode.

[0057] In some embodiments, the process may also comprise pre-treating the surface of the substrate prior to the aerosol jet printing of the repair metal electrode at the location. Additionally, in some embodiments, the pre-treating of the surface of the substrate may expose a buried layer to reduce a contact resistance for a repaired metal electrode relative to a damaged metal electrode.

[0058] In some embodiments, the aerosol jet printing of the repair metal electrode at the location may comprise aerosol jet printing only one repair metal electrode at a time. In some embodiments, the process may also comprise drying the repair metal electrode to remove a volatile component from the repair metal electrode, and the drying of the repair metal electrode may be performed before the sintering of the repair metal electrode. In some embodiments, thesintering of the repair metal electrode may comprise photonically sintering the repair metal electrode. Furthermore, the drying of the repair metal electrode may comprise photonically drying the repair metal electrode. Additionally, in some embodiments, a temperature at the substrate may remain below about 100 degrees Celsius during photonic sintering and during photonic drying.BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

[0060] FIG. 1 is a front view illustrating an example display, in accordance with some embodiments discussed herein;

[0061] FIG. 2 is a cross-sectional view illustrating a cross-section of the display of FIG. 1 about the line A — A where display tiles are illustrated, in accordance with some embodiments discussed herein;

[0062] FIG. 3 is a cross-sectional view illustrating another example display tile that may be used as an alternative to the display tiles of FIG. 2, in accordance with some embodiments discussed herein;

[0063] FIG. 4 is a perspective view illustrating an example display tile having metal electrodes covered by overcoating, in accordance with some embodiments discussed herein;

[0064] FIG. 5 A is a top view illustrating an example assembly comprising metal electrodes on a substrate, in accordance with some embodiments discussed herein;

[0065] FIG. 5B is a front view illustrating the example assembly of FIG. 5 A, in accordance with some embodiments discussed herein;

[0066] FIG. 5C is a side view illustrating the example assembly of FIG. 5A, in accordance with some embodiments discussed herein;

[0067] FIG. 6A is a schematic view illustrating an example photonic device being used to treat metal electrodes of an assembly, in accordance with some embodiments discussed herein;

[0068] FIG. 6B is a perspective view illustrating an example mask that may be utilized in the photonic device of FIG. 6A, in accordance with some embodiments discussed herein;

[0069] FIG. 7A is a schematic, bottom view illustrating an example photonic device, in accordance with some embodiments discussed herein;

[0070] FIG. 7B is a schematic, cross-sectional view illustrating the example photonic device shown in FIG. 7A, in accordance with some embodiments discussed herein;

[0071] FIG. 7C is a schematic, cross-sectional view illustrating the example photonic device shown in FIG. 7A, with a metal electrode on a substrate being exposed thereto, in accordance with some embodiments discussed herein;

[0072] FIG. 7D is a schematic, cross-sectional view illustrating the example photonic device shown in FIG. 7C, where the substrate has been rotated relative to the photonic device, in accordance with some embodiments discussed herein;

[0073] FIG. 8A illustrates a scanning electron microscope image of a silver electrode that has been photonically sintered, in accordance with some embodiments discussed herein;

[0074] FIG. 8B illustrates a scanning electron microscope image of a silver electrode that has been thermally sintered for one hour at 150 degrees Celsius, in accordance with some embodiments discussed herein;

[0075] FIG. 8C illustrates a scanning electron microscope image of a silver electrode that has been thermally sintered for one hour at 200 degrees Celsius, in accordance with some embodiments discussed herein;

[0076] FIG. 9 illustrates a metal electrode comprising silver nanoparticle ink after photonic sintering when the metal electrode undergoes photonic drying before photonic sintering, in accordance with some embodiments discussed herein;

[0077] FIG. 10 is a metal electrode comprising silver nanoparticle ink after photonic sintering when the metal electrode does not undergo any photonic drying before photonic sintering, in accordance with some embodiments discussed herein;

[0078] FIG. 11A is a bottom view illustrating an example damaged assembly with areas where metal electrodes are damaged, in accordance with some embodiments discussed herein;

[0079] FIG. 1 IB is a bottom view illustrating the damaged assembly of FIG. 11A after it has been repaired, in accordance with some embodiments discussed herein;

[0080] FIG. 12A is a perspective view illustrating an example damaged assembly with areas where existing metal electrodes are damaged, in accordance with some embodiments discussed herein;

[0081] FIG. 12B is a perspective view illustrating the damaged assembly of FIG. 12A after it has been repaired, in accordance with some embodiments discussed herein;

[0082] FIG. 13 is a schematic view of a nozzle of an aerosol jet printer, with the aerosol jet printer configured to print a metal electrode on a substrate, in accordance with some embodiments discussed herein;

[0083] FIG. 14 is a flow chart illustrating an example method for assembling and preparing a metal electrode, in accordance with some embodiments discussed herein;

[0084] FIG. 15 is a flow chart illustrating an example method for assembling and preparing a metal electrode, in accordance with some embodiments discussed herein; and

[0085] FIG. 16 is a flow chart illustrating an example method for assembling and preparing a metal electrode, in accordance with some embodiments discussed herein.DETAILED DESCRIPTION

[0086] Example embodiments now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments are shown. Like reference numerals generally refer to like elements throughout. For example, reference numbers 212A, 212B, 312, 412, etc. each refer to metal electrodes. Additionally, any connections or attachments may be direct or indirect connections or attachments unless specifically noted otherwise.

[0087] A front view illustrating an example display 100 is provided in FIG. 1. This display 100 may be a tiled emissive display such as a micro-LED display or an organic light-emitting diode (OLED) display. In micro-LED displays, each pixel can be directly formed by one red, one green, and one blue micro-LED, or formed of three same color micro-LEDs (such as blue or ultraviolet (UV) micro-LEDs) with color converters (such as quantum dots converters). When UV micro-LEDs are used, three color converters convert UV light into red, green, blue lights, respectively. When blue micro-LEDs are used, two color converters convert blue light into green and red lights, respectively. The display may take a variety of forms. In some embodiments, the display may be a borderless display, a bezel free display, or a tiled display, but other displays are also contemplated.

[0088] Further details regarding the display 100 of FIG. 1A are illustrated in the cross- sectional view of FIG. 2. FIG. 2 illustrates a cross-section of the display 100 about the line A — A, with a first display tile 220A and a second display tile 220B being illustrated. Each of the display tiles 220A, 220B has a first side 201A and a second side 201B. A viewer may be positioned on the first side 201 A of the display tiles 220A, 220B and light 244 may be directed from the display tiles 220A, 220B towards the first side 201 A of the display tiles 220A, 220B.

[0089] The first display tile 220A comprises a substrate 202A, and the second display tile 220B comprises a substrate 202B. The substrates 202A, 202B may comprise glass material in some embodiments. Additionally, the substrates 202A, 202B may comprise transparent material in some embodiments.

[0090] One or more light source arrays may also be provided in both the first display tile 220A and the second display tile 220B. For example, in the portion of the first display tile 220A that is illustrated in FIG. 2, a light source array 204A is provided. Additionally, in the portion of the second display tile 220B that is illustrated in FIG. 2, a light source array 204B is provided. Light source arrays may comprise one or more light sources, and the light sources may be configured to generate light 244 having different colors in some embodiments. For example, the light source array 204A comprises a first light source 205A, a second light source 206A, and a third light source 207A. In the illustrated embodiment, the first light source 205 A is configured to generate red light, the second light source 206 A is configured to generate blue light, and the third light source 207A is configured to generate green light. However, these light sources 205A, 206A, 207A may be configured to generate other colors. Additionally, the light source array 204B comprises a first light source 205B, a second light source 206B, and a third light source 207B. In the illustrated embodiment, the first light source 205B is configured to generate red light, the second light source 206B is configured to generate blue light, and the third light source 207B is configured to generate green light. However, these light sources 205B, 206B, 207B may be configured to generate other colors. In some embodiments, a different number of light source(s) may be included in each light source array, and the light source(s) may be positioned differently on a display tile. In some embodiments, light sources in a light source array 204A, 204B may be configured to generate light having the same color initially, and the initial color of the light may be converted to a different color before the light exits a display tile 220A, 220B. This may be accomplished using quantum structures such as quantum dots. Light 244 from the light source arrays 204A, 204B may be emitted in directions indicated by the arrows adjacent to the light source arrays 204A, 204B in FIG. 2.

[0091] In each of the display tiles 220A, 220B, pixel structures may be provided. A pixel structure 208A is provided in the first display tile 220A. This pixel structure 208A is positioned between the light source array 204A and the substrate 202A, but the pixel structure 208A may be positioned differently in a display tile in other embodiments. A pixel structure 208B is provided in the second display tile 220B, with the pixel structure 208B being positioned between the light source array 204B and the substrate 202B, but the pixel structure 208B may be positioned differently in a display tile in other embodiments. The pixel structures 208A, 208B may be configured to connect contact pads to light sources, and the pixel structures 208A, 208B may include conductive metal traces that are lithographically deposited on a tile. Pixelstructures 208A, 208B may include thin film transistors that are configured to drive light sources.

[0092] The first display tile 220A and the second display tile 220B also comprise contact pads 210. These contact pads 210 may comprise copper material, indium tin oxide, gold, or titanium in some embodiments. The contact pads 210 are configured to facilitate electrical connections between the light source arrays and driver electronics and circuitry .

[0093] The first display tile 220A also comprises a metal electrode 212A, and the second display tile 220B also comprises a metal electrode 212B. These metal electrodes 212A, 212B both comprise silver material, but the metal electrodes 212A, 212B may comprise other materials in other embodiments. The metal electrodes 212A, 212B extend from the first side 201A of the display tiles 220A, 220B to the second side 201B of the display tiles 220A, 220B in some embodiments. In doing so, the metal electrodes 212A, 212B extend around the sides 201C of the display tiles 220A, 220B and avoid extending directly through the substrates 202A, 202B. The metal electrodes 212A, 212B therefore allow for electrical components on the first side 201A of the display tiles 220A, 220B to be connected to electrical components on the second side 201B of the display tiles 220A, 220B. Overcoating 214A may be positioned on the metal electrode 212A, and overcoating 214B may be positioned on the metal electrode 212B. The overcoating 214A, 214B may protect the metal electrodes 212A, 212B and may also hide the metal electrodes 212A, 212B as the metal electrodes 212A, 212B travel over the sides 201C of the display tiles 220A, 220B.

[0094] Another example display tile 320 is illustrated in FIG. 3, and this display tile 320 may be used as an alternative to the display tiles 220A, 220B of FIG. 2. The display tile 320 has a first side 301A and a second side 301B. A viewer may be positioned on the first side 301A of the display tile 320 and light 344 may be directed from the display tile 320 towards the first side 301A of the display tile 320.

[0095] The display tile 320 comprises substrate 303B, and this substrate 303B may comprise glass material in some embodiments. Additionally, the substrate 303B may comprise transparent material in some embodiments. One or more light source arrays may also be provided in the display tile 320. For example, in the portion of the display tile 320 that is illustrated in FIG. 3, a light source array 304 is provided. Light source arrays may comprise one or more light sources, and the light sources may be configured to generate light 344 having different colors in some embodiments. For example, the light source array 304 comprises a first light source 305, a second light source 306, and a third light source 307. In the illustratedembodiment, the first light source 305 is configured to generate red light, the second light source 306 is configured to generate blue light, and the third light source 307 is configured to generate green light. However, these light sources 305, 306, 307 may be configured to generate other colors. In some embodiments, a different number of light source(s) may be included in each light source array, and the light source(s) may be positioned differently on a display tile. In some embodiments, light sources in a light source array 304 may be configured to generate light having the same color initially, and the initial color of the light may be converted to a different color before the light exits a display tile 320. This may be accomplished using quantum structures such as quantum dots. Light 344 from the light source array 304 may be emitted towards the first side 301 A of the display tile 320.

[0096] A pixel structure 308 is also provided in the display tile 320. The light source array 304 is positioned within the pixel structure 308 in FIG. 3, but the light source array 304 may be positioned outside of the pixel structure 308 in other embodiments. The pixel structure 308 is positioned between the second substrate 303B and the resin 316 in the illustrated embodiment, but the pixel structure 308 may be positioned differently in a display tile in other embodiments. The pixel structure 308 may include conductive metal traces that are lithographically deposited on a tile. Pixel structure 308 may include thin film transistors that are configured to drive light sources.

[0097] A color filter 318 and resin 316 are also included in the display tile 320 of FIG. 3. Light 344 from the light source array 304 may travel towards the first side 301A so that the light 344 passes through the color filter 318 and the resin 316. In some embodiments, the color filter 318 may generally possess uniform properties throughout the color filter 318. However, in other embodiments, the color filter 318 may have different properties at different positions in the color filter 318. The resin 316 may be transparent, and the resin 316 may space the light source array 304 from the color filter 318.

[0098] The display tile 320 also comprises a metal electrode 312. The metal electrode 312 comprises silver material, but the metal electrode 312 may comprise other materials in other embodiments. The metal electrode 312 extends from the side 301B of the display tile 320 to the side 301C of the display tile 320, and the metal electrode 312 also extends from the side 301C to the side 301 A so that the metal electrode 312 extends partially along the side 301 A relative to the substrate 303B. Thus, the metal electrode 312 avoids extending directly through the substrate 303B. Overcoating 314 may be positioned on the metal electrode 312, and the overcoating 314 may protect the metal electrode 312 and also hide the metal electrode 312 asthe metal electrode 312 travel over the side 301C of the display tile 320. The display tile 320 also comprises contact pads 310 having properties similar to the properties of contact pads 210 of FIG. 2.

[0099] As noted above, wrap-around metal electrodes of display tiles may be covered by overcoating. FIG. 4 illustrates an example display tile 420 having metal electrodes 412 covered by overcoating 414. The display tile 420 comprises a substrate 402. The substrate 402 comprises a first side 401 A, a second side 401B, and a third side 401C. The first side 401 A and the second side 40 IB both extend in a plane parallel to the X-Z plane and face in opposite directions. The third side 401C extends in a plane parallel to the Y-Z axis. The substrate 402 may comprise a glass material, and the substrate 402 may be transparent. Electrically conductive lines 422 are positioned on the substrate 402. These electrically conductive lines 422 are positioned on the first side 401A and on the second side 401B, but the electrically conductive lines 422 do not extend onto the third side 401C. Metal electrodes 412 are positioned on all of the sides 401A, 401B, 401C so that the metal electrodes 412 contact electrically conductive lines 422 on the first side 401A and the second side 401B. The overcoating 414 may extend onto the first side 401 A and the second side 401B for an overflow distance B that is greater than zero. By having the overcoating 414 extend for some overflow distance B, additional protection may be provided for the metal electrodes 412 to avoid damage to the metal electrodes 412.

[0100] An example assembly 528 comprising metal electrodes 512A-512D on a substrate526 is illustrated in FIGS. 5A-5C. FIG. 5A illustrates a top view, FIG. 5B illustrates a front view, and FIG. 5C illustrates a side view. The substrate 526 is illustrated having a first side 525 A extending in a plane that is parallel to the Y-Z plane, a second side 525B extending in a plane that is parallel to the X-Z plane, and a third side 525C extending in a plane that is parallel to the X-Y plane.

[0101] The assembly 528 comprises a plurality of metal electrodes. These metal electrodes include a first metal electrode 512A, a second metal electrode 512B, a third metal electrode 512C, and a fourth metal electrode 512D. Each of these metal electrodes 512A-512D may comprise silver, but the metal electrodes 512A-512D may comprise other materials in some embodiments. As illustrated in FIGS. 5A-5C, the metal electrodes 512A-512D each are positioned on the first side 525 A and wrap around to the second side 525B. In FIG. 5B, a fillet527 is visible at the edge between the first side 525A and the second side 525B. The metal electrodes 512A-512D extend over this fillet 527. By using the metal electrodes 512A-512D,electrical components on different sides of the substrate 526 may be attached together. While four metal electrodes 512A-512D are illustrated in the assembly 528, any number of metal electrodes 512A-512D may be utilized in other embodiments. In some embodiments, the metal electrodes 512A-512D may extend from one surface on the substrate 526 to an opposite surface on the substrate 526 similar to the metal electrodes 212A, 212B of FIG. 2. As illustrated in FIG. 5C, the metal electrodes 512A-512D may each have a width C. The width C may range from about 20 to about 200 micrometers in some embodiments, but other widths may also be used.

[0102] FIG. 6 A illustrates an example photonic device 636 being used to treat metal electrodes 612 of an assembly 628. In some embodiments, the photonic device 636 may be used to photonically dry the metal electrodes 612 of the assembly 628. Additionally or alternatively, the photonic device 636 may be used to photonically sinter the metal electrodes 612 of the assembly 628. The metal electrodes 612 and the assembly 628 may be included in a display similar to the display 100 of FIG. 1 in some embodiments. A photonic device 636 may comprise a lamp 638 and a mask 640. The mask 640 may be positioned between the lamp 638 and the metal electrode 612 on the assembly 628. The lamp 638 is configured to generate light 644, and this light 644 may be emitted towards the mask 640. In some embodiments, the lamp 638 may be configured to emit light 644 only in a direction towards the mask 640. In other embodiments, reflective material may be positioned around the lamp 638 to cause light emitted in other directions to ultimately be reflected towards the mask 640. In some embodiments, the light 644 may be broad wavelength ultraviolet-near infrared (UV-NIR) high intensity pulsed light, and the lamp 638 may be a xenon light source that is configured to generate high intensity pulses of light.

[0103] The mask 640 comprises defines an internal volume 642, and light 644 may be directed into the internal volume 642. A portion of the light 644 may ultimately be emitted out of a slot 646 in the mask 640. Once emitted out of the slot 646, the light 644 may be emitted towards the metal electrodes 612 of the assembly 628. Due to the high optical density of the metal electrodes 612 relative to the substrate 626, photonic energy from light 644 may largely be directed towards the metal electrodes 612 rather than the substrate 626. The assembly 628 may be similar to the assembly 528 of FIGS. 5A-5C.

[0104] Further details regarding the mask 640 are illustrated in FIG. 6B. The mask 640 comprises a wall that defines a slot 646 therein with a semi-circular shape. However, the slot may have a variety of other shapes. For example, the slot 646 may comprise a circular shape,an oval shape, a rounded shape, a rectangular shape, a triangular shape, a polygonal shape, or an asymmetrical shape. The mask 640 may be configured to allow a portion of the photonic energy of light from the lamp to pass through the slot 646, and the wall formed by remaining portions of the mask 640 may limit the amount of photonic energy emitted towards other locations.

[0105] The mask 640 comprises a base 641, and the base 641 generally covers a rectangular footprint in a plane parallel to the X-Z axis, but various edges of the base 641 may be rounded with fillets of varying sizes. The mask 640 defines an extended region 645. This extended region 645 extends from the base 641 to the slot 646. The extended region 645 generally possesses a rectangular pyramid shape, but other shapes may also be utilized. The presence of the extended region 645 allows light to be reflected towards the slot 646 so that light may be focused at the slot 646. The inclusion of a mask 640 having a slot 646 may allow for local application of photonic energy during photonic drying and / or photonic sintering to avoid damage to other sensitive components. For example, other components may be present in the display or on a substrate having a high optical density that are sensitive to photonic energy, and the wall formed by the mask 640 may limit the amount of photonic energy extending towards these high optical density components.

[0106] In some embodiments, the mask 640 may be removed from a photonic device and replaced with another suitable mask 640. For example, a mask having a slot with a first size or shape may be removed and replaced with another mask having a slot with a second size or shape. This may enable the slot size or shape to be easily adjusted to adapt to the particular task at hand. For example, the different slot size or shape may allow for different areas of a substrate surface or other assembly components to be exposed to light from the photonic device. The ability to remove and replace the mask 640 may also allow maintenance to be conducted more easily and may allow for easy replacement of components. Masks may be removed and replaced for other reasons as well to change the properties of the photonic device. In some embodiments, the mask may comprise a first portion (e.g., the base 641) and a second portion that is removably attachable to the first portion. This may similarly allow for further customization of the mask and the photonic device to adapt to the particular task at hand.

[0107] Another example photonic device 736 is illustrated in the schematic views of FIGS. 7A and 7B. The photonic device 736 comprises a lamp 738. The photonic device 736 also comprises a mask 740 defining a slot 746. Only a portion of the mask 740 is illustrated in FIG. 7 A so that the lamp 738 may be seen, but the mask 740 may generally prevent photonic energyfrom extending past the mask 740 at areas other than the slot 746. The slot 746 comprises a rectangular shape, with a first dimension D and a second dimension E. In some embodiments, the first dimension D may range from about 0.25 centimeters to about 40 square centimeters, about 0.5 centimeters to about 20 square centimeters, or about 1 centimeter to about 10 centimeters. In some embodiments, the second dimension E may range from about 0.25 centimeters to about 40 square centimeters, about 0.5 centimeters to about 20 square centimeters, or about 1 centimeter to about 10 centimeters. In some embodiments, a mask 740 may be selected with a slot 746 that has a first dimension D or a second dimension E that is approximately equal to the width C (see FIG. 5C) of a metal electrode 512A (see FIG. 5C). The cross-sectional area of the slot 746 may be between about 1 square centimeter and about 10 square centimeters in some embodiments, but the slot 746 may comprise different cross- sectional areas in other embodiments.

[0108] As illustrated in FIG. 7B, light 744 may be emitted from the lamp 738. In some embodiments, the mask 740 may comprise a material that is configured to allow the light 744 to reflect off of the internal walls of the mask 740. By doing so, less light will be absorbed by the walls of the mask 740 and more light 744 may reach the slot 746. Reflective material may include mirrors or optical lenses in some embodiments. Additionally or alternatively, surfaces of the mask 740 may be roughened to generate more light scattering, and this may result in a reduction of the intensity of light through the slot, this may avoid focusing of light, and this may avoid the generation of hot spots. In some embodiments, the internal walls of the mask 740 may comprise a lighter color such as white so that less light will not be absorbed by the walls of the mask 740. While the slot 746 comprises a rectangular shape, the slot 746 may comprise another shape in other embodiments. For example, the slot 746 may comprise a circular shape, an oval shape, a rounded shape, a triangular shape, a polygonal shape, or an asymmetrical shape. The photonic device 736 may be optimized for a particular application. For example, the photonic device 736 may be optimized to be used for a particular composition of the metal electrode (e.g., where silver, gold, or some other metal is used). The photonic device 736 may also be optimized for metal electrodes, substrates, and assemblies having different dimensions and / or different geometries. The photonic device 736 may also be optimized for different exposure areas on an assembly. Additionally, photonic device 736 may be altered based on the position, shape, and size of areas where exposure is unwanted (e.g., where other components sensitive to photonic sintering or drying are present). In some embodiments, the photonic device 736 may be altered by removing mask 740 and replacingmask 740 with another mask having a slot with a different size or shape. However, a mask may optionally include other features thereon to adjust the size of the slot without removing the mask — for example, a slidable wall may be shifted so that it covers a desired portion of a slot to effectively change the size of the opening formed by the slot.

[0109] Photonic devices 736 and other photonic devices described herein may be used to emit photonic energy towards metal electrodes 712. The metal electrodes 712 may be printed with high optical density relative to other components like the substrate 726. Thus, when photonic energy is emitted out of a slot 746 in a photonic device 736, more of the photonic energy may be directed towards the high optical density metal electrode 712 and less of the photonic energy may be directed towards the lower optical density substrate 726. By using photonic device 736 for drying and / or sintering of metal electrodes, a temperature at the substrate 726 may remain below about 100 degrees Celsius when the photonic device 736 is in an activated state. The mask 740 may beneficially limit the amount of photonic energy travelling to other portions of an assembly 728 other than the area near the metal electrodes 712, limiting exposure to other components on the substrate 726 that may have a high optical density or that may be sensitive to photonic energy. In some embodiments, the mask 740 may be selected so that the size of the slot 746 is about the same as the size of the metal electrode 712. For example, the slot 746 may be selected so that the width of the slot 746 is approximately equal to a width of the metal electrode 712.

[0110] The photonic device 736 of FIGS. 7 A and 7B may be used to treat metal electrodes on one or more surfaces of an assembly. For example, in FIGS. 7C and 7D, the photonic device 736 is being used to treat an assembly 728, with the assembly 728 comprising a substrate 726 and a metal electrode 712. The metal electrode 712 extends from a first side 725A of the substrate 726 to a second side 725B of the substrate 726. Because of the three-dimensional nature of the metal electrode 712 and because the metal electrode 712 extends from one side to another, a single orientation for photonic exposure may not be sufficient for proper sintering. In FIG. 7C, the photonic device 736 is being used to treat a portion of the metal electrode 712 positioned on the first side 725A of the substrate 726. However, the photonic device 736 and / or the assembly 728 may be repositioned as illustrated in FIG. 7D so that the photonic device 736 may be used to treat a portion of the metal electrode 712 positioned on the second side 725B of the substrate 726. Thus, the photonic device 736 may be used to expose all portions of a metal electrode regardless of the side of the substrate 726 that the metal electrode is on. Movement of the photonic device 736 relative to the substrate 726 may ensure that sintering ordrying is performed evenly. In FIGS. 7C and 7D, the assembly 728 is rotated only 90 degrees, but the assembly 728 may be rotated further where necessary to fully expose the metal electrode 712 to light from the photonic device 736. In some embodiments, the assembly 728 may be rotated in smaller increments (e.g., 10 degrees, 20 degrees, 22.5 degrees, 45 degrees, etc.) relative to the photonic device 736. Rotation in smaller increments may be beneficial for angled surfaces and / or to more evenly apply light. By rotating the assembly 728 relative to the photonic device 736 or by rotating the photonic device 736 relative to the assembly 728, the metal electrode 712 of the assembly 728 may be more evenly dried and / or sintered.

[0111] In some embodiments, multiple photonic devices may be utilized to photonically dry or photonically sinter metal electrodes from different angles or positions, and this may eliminate or reduce the need to move the photonic devices and / or the assembly relative to each other. Where multiple photonic devices are used, the photonic devices may each possess structures similar to those described in reference to FIGS. 6A-6B and FIGS. 7A-7D. Where multiple photonic devices are utilized, the photonic devices may target different locations of a metal electrode or the photonic devices may emit photonic energy at different angles towards the same general location on a metal electrode. In some embodiments, one photonic device may be utilized for photonic drying and another photonic device may be utilized for photonic sintering. However, in other embodiments, a single photonic device may be utilized for both photonic drying and for photonic sintering, and this may make manufacturing processes more efficient, less complex, and more cost-effective as other components required for thermal drying or thermal sintering may be omitted.

[0112] The photonic device 736 and other photonic devices described herein may be utilized to photonically sinter metal electrodes. Where photonic devices are utilized to sinter metal electrodes, the amount of energy and optical power may vary based on the requirements for a particular application. In some embodiments, the photonic device 736 may be utilized to deliver about 1.65 joules per square centimeter to about 7.2 joules per square centimeter for each emitted pulse through the slot 746, but the photonic device 736 operate at different intensities in other embodiments. For example, in some embodiments, the photonic device 736 may operate at an intensity of up to about 60 joules per square centimeter or more for each emitted pulse. Optical energy may be delivered in a series of pulses. In some embodiments, the pulses may each last about 0.1 milliseconds to about 1.5 milliseconds, about 0.2 milliseconds to about 1.25 milliseconds, or about 0.25 milliseconds to about 1 millisecond. In some embodiments, total pulses may be provided at an average of about 150 joules per squarecentimeter to about 320 joules per square centimeter, about 165 joules per square centimeter to about 290 joules per square centimeter, or about 187.5 joules per square centimeter to about 281.25 joules per square centimeter. In some embodiments, pulses may be provided at an optical power of about 2 kilowatts per square centimeter to about 15 kilowatts per square centimeter, about 3.5 kilowatts per square centimeter to about 12.5 kilowatts per square centimeter, or about 5 kilowatts per square centimeter to about 10 kilowatts per square centimeter. In some embodiments, pulse frequencies for the photonic device 736 and other photonic devices discussed herein may be about 0.25 hertz to about 4 hertz, or pulse frequencies may be about 0.5 hertz to about 2 hertz. However, the properties for the photonic device 736 may be adjusted in other embodiments.

[0113] Typically, in a photonic sintering process, printed metal ink patterns are exposed to one or more short high intensity pulses of light of a specified power and duration, and these pulses of light primarily comprise light within the visible spectrum. By contrast, in some embodiments herein, variable (e.g., ramped) intensity profiles may be used by a photonic device or another device. For example, a photonic device may be configured to sinter or dry the metal electrode by generating a first set of pulse(s) of photonic energy and then later generating a second set of pulse(s) of photonic energy towards the metal electrode. In the second set of pulse(s) and any subsequent sets of pulse(s), the photonic intensity of the pulse(s) may differ in photonic intensity relative to the first set of pulse(s) (and / or prior sets of pulse(s)). This may occur by changing the number of pulses relative to the number of pulses in the first set of pulse(s). The change in photonic intensity may also be accomplished by changing the frequency of pulses relative to the frequency of pulses in the first set of pulse(s). The photonic intensity may also be changed by altering the duration of pulses relative to the duration of pulses for the first set of pulse(s), which would result in a change in the pulse width for the second set of pulse(s). The photonic intensity may be changed by altering the voltage level relative to a voltage level applied for the first set of pulse(s). By changing the voltage level, the pulse maximum of a pulse may be changed for the second set of pulse(s). A change in photonic intensity may also be accomplished by changing the power level relative to the power level for the first set of pulse(s). A change in photonic intensity may also be accomplished by changing the relative position of the substrate relative to the light source so that the distance between the light source and the substrate are altered.

[0114] In some embodiments, the ramped intensity profiles may increase the intensity profile over time. In the second set of pulse(s) and any subsequent sets of pulse(s), the photonicintensity of the pulse(s) may be increased. This may occur by increasing the number of pulses relative to the number of pulses in the first set of pulse(s). The increase in photonic intensity may additionally or alternatively be accomplished by increasing the frequency of pulses relative to the frequency of pulses in the first set of pulse(s). The photonic intensity may additionally or alternatively be increased by increasing the duration of pulses relative to the duration of pulses for the first set of pulse(s), which would result in an increase in the pulse width for the second set of pulse(s). The photonic intensity may be increased by increasing the voltage level relative to a voltage level applied for the first set of pulse(s). By increasing the voltage level, the pulse maximum of a pulse may be increased for the second set of pulse(s). An increase in photonic intensity may also be accomplished by increasing the power level relative to the power level for the first set of pulse(s). Where a ramped intensity profile is used, a cool-down phase may be included between exposures. Additionally, to change the power level in some embodiments, the distance between the ink and the light source may be adjusted. Additionally or alternatively, lenses and / or mirrors may be adjusted to concentrate power at differing levels.

[0115] Ramped intensity profiles may be beneficial to provide higher dosages of photonic energy to metal electrodes while minimizing the risk of damage to the metal electrodes. Use of single dosage approaches may lead to delamination at a metal electrode from the substrate and / or damage of the metal electrode, but ramped intensity profiles may beneficially reduce the risk of delamination and damage at the metal electrode. This may result in improved electrical performance — for example, metal electrodes formed with a ramped intensity profile may have a reduced resistivity compared to metal electrodes formed by a single dosage of photonic energy. Ramped intensity profiles may allow ink to consolidate more completely during formation of metal electrodes. Ramped intensity profiles may also result in improved adhesion compared to other approaches using a single dosage of photonic energy. Ramped intensity profiles may be tuned to a variety of inks, to a variety of metal electrode dimensions, and to a variety of geometries.

[0116] Table 1 illustrates the effects of a ramped intensity profile relative to other approaches using constant power. In each of the samples and for each exposure, the pulse length used was about 442 microseconds.

[0117] While higher power levels tend to increase the risk of damage to metal electrodes, higher power levels also led to a reduction in the resistivity. For the first sample and the second sample, a ramped photonic intensity profile was used where the intensity and power level increased between certain exposures. For the third sample and the fourth sample, constant power is used. The intact metal electrode percentage was obtained by visually inspecting samples with a microscope to ensure that they remained intact. A metal electrode may be considered to be intact where the metal electrode has a measurable electric response, and the presence or absence of a measurable electric response was used as the primary method for determining whether or not metal electrodes were intact. Adjustments in the power level and intensity may be accomplished by changing the distance of a lamp of the photonic device to the sample, but adjustments in the power level and intensity may be accomplished in other ways. Samples with ramped photonic intensity profiles (the first sample and second sample) had an improved electrical performance and adhesion relative to samples with a single dosage (the third sample and fourth sample).

[0118] The first sample was exposed three different times. With the first exposure of the first sample, the intensity was about 52 joules per square centimeter and the power level was about 7.8 kilowatts per square centimeter. After the first exposure to the first sample, about 100 percent of metal electrodes remained intact and the resistivity at the metal electrodes was about 13.3 microohm centimeters, which amounts to about 8.3 times the bulk resistivity of silver. With the second exposure of the first sample, the intensity was about 62 joules per square centimeter and the power level was about 9.4 kilowatts per square centimeter. After the second exposure to the first sample, about 100 percent of the metal electrodes remained intact and the resistivity at the metal electrodes was about 10.1 microohm centimeters, which amounts toabout 6.3 times the bulk resistivity of silver. With the third exposure of the first sample, the intensity was about 62 joules per square centimeter and the power level was about 9.4 kilowatts per square centimeter. After the third exposure to the first sample, about 100 percent of the metal electrodes remained intact and the resistivity at the metal electrodes was about 9.6 microohm centimeters, which amounts to about 6.0 times the bulk resistivity of silver.

[0119] The second sample was exposed three different times. With the first exposure of the second sample, the intensity was about 62 joules per square centimeter and the power level was about 9.4 kilowatts per square centimeter. After the first exposure to the second sample, about 100 percent of metal electrodes remained intact and the resistivity was about 11.5 microohm centimeters, which amounts to about 7.2 times the bulk resistivity of silver. With the second exposure of the second sample, the intensity was about 74 joules per square centimeter and the power level was about 11.2 kilowatts per square centimeter. After the second exposure to the second sample, about 100 percent of the metal electrodes remained intact and the resistivity was about 8.6 microohm centimeters, which amounts to about 5.4 times the bulk resistivity of silver. With the third exposure of the second sample, the intensity was about 89 joules per square centimeter and the power level was about 13.4 kilowatts per square centimeter. After the third exposure to the second sample, about 100 percent of the metal electrodes remained intact and the resistivity was about 7.8 microohm centimeters, which amounts to about 4.9 times the bulk resistivity of silver.

[0120] For the third sample and the fourth sample, constant power was used and samples were subjected to only one exposure. With the single exposure of the third sample, the intensity was about 74 joules per square centimeter and the power level was about 11.2 kilowatts per square centimeter. After exposure to the third sample, only about 85 percent of metal electrodes remained intact and the resistivity was about 8.5 microohm centimeters, which amounts to about 5.3 times the bulk resistivity of silver. With the single exposure of the fourth sample, the intensity was about 89 joules per square centimeter and the power level was about 13.4 kilowatts per square centimeter. After exposure to the fourth sample, only about 12 percent of metal electrodes remained intact and the resistivity was about 17.4 microohm centimeters, which amounts to about 10.9 times the bulk resistivity of silver. Relative to the first and second samples (which used a ramped photonic intensity profile), the third and fourth samples had more variability in the color and less uniformity in color, and this indicates poorer adhesion and less uniform sintering for the third and fourth samples. The third and fourth samples alsopossessed more burnt material at certain locations relative to the first sample and the second sample.

[0121] The results of testing set forth in Table 1 demonstrate that the first sample and the second sample remained intact even after a number of exposures, but the third and fourth samples were severely damaged. Notably, 100 percent of the metal electrodes remained intact for the second sample despite using intensity and power levels similar those used for the third and fourth sample. The second exposure of the second sample had the same intensity and power level as the single exposure to the third sample, with the intensity being about 74 joules per square centimeter and with the power level being about 11.2 kilowatts per square centimeter. Additionally, the third exposure of the second sample had the same intensity and power level as the single exposure to the fourth sample, with the intensity being about 89 joules per square centimeter and with the power level being about 13.4 kilowatts per square centimeter. This tends to show that the ramped photonic intensity profile was beneficial and that the initial exposure of metal electrodes to low intensity pulses was beneficial to maintain a high number of intact metal electrodes.

[0122] While ramped photonic intensity profiles are contemplated herein for use with photonic devices, it should be understood that ramped intensity profiles may be used for devices other than photonic devices. For example, ramped intensity profiles may be used for other sintering approaches and / or drying approaches that do not involve a photonic device (e.g., laser sintering devices, thermal sintering devices, thermal drying devices, etc.).

[0123] Scanning electron microscope images were also taken of metal electrodes that underwent photonic sintering and thermal sintering. FIG. 8A illustrates a scanning electron microscope image of a metal electrode 848 comprising silver material that has been photonically sintered. Photonic sintering results in silver nanoparticles 848B generally being grouped together in high concentrations relative to the images of FIGS. 8B and 8C. Photonic sintering may achieve low resistivities that are less than ten times (lOx) the bulk resistivity of silver. With the silver nanoparticles 848B being concentrated together, pores 848A are formed in the material. The high concentrations of silver nanoparticles 848B in the material illustrated in FIG. 8A are beneficial to provide highly conductive materials, and thus high conductivity may be accomplished without exposing an entire substrate to high temperatures. The metal electrode 848 illustrated in the scanning electron microscope image of FIG. 8 A was prepared by subjecting the metal electrode 848 to fifteen pulses at about 0.5 hertz to generate about 45 joules per centimeter squared and about 5 kilowatts per centimeter squared.

[0124] FIG. 8B illustrates a scanning electron microscope image of another metal electrode 850 comprising silver material that has been thermally sintered for one hour at 150 degrees Celsius, and FIG. 8C illustrates a scanning electron microscope image of a metal electrode 852 comprising silver material that has been thermally sintered for one hour at about 200 degrees Celsius. With these thermal sintering approaches, the silver nanoparticles 850B, 852B are grouped together in lower concentrations relative to the silver nanoparticles 848B of FIG. 8 A. Pores 850A, 852A are formed in the material. Relative to the silver metal electrode 848 illustrated in FIG. 8A, the silver metal electrode 850 of FIG. 8B and the silver metal electrode 852 of FIG. 8C comprise a larger number of pores 850A, 852A, with the pores 850A, 852A having a smaller size than the pores 848A of FIG. 8A. Due to this different structure in the silver metal electrodes 850, 852, the silver metal electrodes 850, 852 are less electrically conductive than the silver metal electrode 848 of FIG. 8A. For silver metal electrodes 850, 852, there are a significant number of small silver nanoparticles that remain unconnected to the adjacent particles. The large number of small pores 850A, 852A in the thermally sintered silver metal electrodes 850, 852 disrupts the current path through the silver metal electrodes 850, 852 causing increased line resistivity.

[0125] Drying may be performed before sintering of metal electrodes in some embodiments. In some embodiments, photonic devices 736 may be utilized to photonically dry metal electrodes before performing any sintering on metal electrodes. Photonic drying results in the removal of solvents and / or other volatile components from metal electrodes. After metal electrodes are printed, it may be beneficial to dry metal electrodes so that solvents and / or other volatile components are removed from metal electrodes before performing any sintering. When sintering is performed without any drying completed beforehand, then sintering may result in the metal electrodes being exposed to high intensity light pulses, and the high intensity light pulses may result in rapid volatilization of ink components that may damage the metal electrode.

[0126] Benefits of photonic drying are illustrated in FIGS. 9 and 10. FIG. 9 illustrates a metal electrode 956 comprising silver nanoparticle ink after photonic sintering when the metal electrode 956 undergoes photonic drying before photonic sintering. By contrast, the metal electrode 1056 of FIG. 10 illustrates silver nanoparticle ink after photonic sintering when the metal electrode 1056 does not undergo any photonic drying before photonic sintering.

[0127] In the metal electrode 956 of FIG. 9, the metal electrode 956 extends linearly with a first edge 957A and a second edge 957B. The metal electrode 956 generally extends in astraight line with relatively smooth edges 957A, 957B. A limited number of pores are present in the metal electrode 956 that may interrupt the electrical conductivity of the metal electrode 956.

[0128] In the metal electrode 1056 of FIG. 10, the metal electrode 1056 comprises silver nanoparticle ink after photonic sintering, when the metal electrode 1056 does not undergo any photonic drying before photonic sintering. Metal electrode 1056 is intended to extend linearly, with a first edge 1057A and a second edge 1057B being parallel to each other. However, the first edge 1057A and the second edge 1057B deviate substantially from a straight shape, with significant disruptions in the linear shape of the second edge 1057B. A pore 1060 is also positioned in the metal electrode 1056, and this pore 1060 interrupts the electrical conductivity of the metal electrode 1056. Thus, the metal electrode 1056 is in need of repair to bridge the pore 1060 to make the metal electrode 1056 electrically conductive again.

[0129] The use of photonic drying techniques rather than thermal drying techniques may be beneficial for various reasons. Thermal drying techniques are often time consuming, taking up to an hour in the oven before sintering may occur. Additionally, thermal drying techniques often require temperatures higher than the processing limits of the substrates in which the metal electrodes are deposited. For example, where the processing limit for a substrate requires always maintaining the temperature of the substrate under 100 degrees Celsius, thermal drying techniques may not be a viable option. The required temperature for thermal drying techniques may depend on the solvents / organic components that are present in the metal ink. With thermal drying techniques, heat is generally applied evenly to a substrate and electrodes — thus, to heat electrodes to a sufficiently high temperature, a substrate must also be heated to a similar temperature (e.g., above 100 degrees Celsius).

[0130] Photonic drying may also allow for substrates and other sensitive components to be exposed to lower temperatures than would be possible in thermal drying, and photonic drying may be performed more quickly than thermal drying. The use of photonic drying may also result in comparable resistivity for metal electrodes relative to thermal drying. To evaluate the electrical performance of photonically sintered metal electrodes, various metal electrodes were tested after being subjected to different drying conditions and sintering conditions. The results of this testing are illustrated in Table 2.

[0131] As demonstrated in Table 2, performance of photonic drying before sintering resulted in comparable resistivity relative to test cases where thermal drying was performed before sintering. In each of the test cases included in Table 2, the metal electrode comprised silver material.

[0132] In the first test case, a metal electrode was subjected to a temperature of about 95 degrees Celsius for about 20 minutes to complete the initial drying operation. After the initial drying operation was completed, the metal electrode was then subjected to photonic sintering, with 15 pulses occurring at a frequency of about 0.5 hertz, with an intensity level of about 45 joules per square centimeter, and with a power level of about 4.2 kilowatts per square centimeter. The metal electrode in this first test case had a resistivity of about 20.6 microohm centimeter, which amounts to about 12.9 times the bulk resistivity of silver.

[0133] In the second test case, a metal electrode was subjected to photonic drying to complete the initial drying operation. During photonic drying, the metal electrode was subjected to 600 pulses occurring at a frequency of about 2 hertz (which equates to about 5 minutes), with an intensity level of about 360 joules per square centimeter, and with about 3 kilowatts per square centimeter. After the initial drying operation was completed, the metal electrode was then subjected to photonic sintering, with 15 pulses occurring at a frequency of about 0.5 hertz, with an intensity level of about 45 joules per square centimeter, and with a power level of about 4.2 kilowatts per square centimeter. The metal electrode in this second test case had a resistivity of about 22.7 microohm centimeters, which amounts to about 14.2 times the bulk resistivity of silver.

[0134] In the third test case, a metal electrode was subjected to a temperature of about 95 degrees Celsius for about 20 minutes to complete the initial drying operation. After the initialdrying operation was completed, the metal electrode was then subjected to photonic sintering, with 15 pulses occurring at a frequency of about 0.5 hertz, with about 52 joules per square centimeter, and with about 7.8 kilowatts per square centimeter. The metal electrode in this third test case had a resistivity of about 7.4 microohm centimeters, which amounts to about 4.6 times the bulk resistivity of silver.

[0135] In the fourth test case, a metal electrode was subjected to photonic drying to complete the initial drying operation. During photonic drying, the metal electrode was subjected to 600 pulses occurring at a frequency of about 2 hertz (which equates to about 5 minutes), with an intensity level of about 360 joules per square centimeter, and with a power level of about 3 kilowatts per square centimeter. After the initial drying operation was completed, the metal electrode was then subjected to photonic sintering, with 15 pulses occurring at a frequency of about 0.5 hertz, with an intensity level of about 52 joules per square centimeter, and with a power level of about 7.8 kilowatts per square centimeter. The metal electrode in this fourth test case had a resistivity of about 8.2 microohm centimeters, which amounts to about 5.1 times the bulk resistivity of silver.

[0136] The results of Table 2 illustrate that performance of photonic drying before sintering resulted in comparable resistivity relative to test cases where thermal drying was performed before sintering. In the first and second test cases, the photonic sintering conditions were the same — the only differences between these two test cases were the use of thermal drying in the initial drying operation for the first test case and the use of photonic drying in the initial drying operation for the second test case. The first test case resulted in a resistivity of 20.6 microohm centimeters while the second test case resulted in a resistivity of 22.7 microohm centimeters, so the use of photonic drying rather than thermal drying resulted in an increase of only 2.1 microohm centimeters in the resistivity. This amounts to an increase of about 10 percent in resistivity.

[0137] In the third and fourth test cases, the photonic sintering conditions were again the same — the only differences between these two test cases were the use of thermal drying in the initial drying operation for the third test case and the use of photonic drying in the initial drying operation for the fourth test case. The third test case resulted in a resistivity of 7.4 microohm centimeters while the fourth test case resulted in a resistivity of 8.2 microohm centimeters, so the use of photonic drying rather than thermal drying resulted in an increase of only 0.8 microohm centimeters in the resistivity. This amounts to an increase of about 10 percent in the resistivity.

[0138] The drying conditions and sintering conditions of Table 2 are merely exemplary, and other conditions may be used to prepare metal electrodes in other embodiments. It may be beneficial to utilize different conditions to prepare metal electrodes based on the type of material used in the metal electrode, the dimensions of the metal electrode, and / or the geometry of the metal electrode. For example, the energy dosage may be adjusted in terms of magnitude frequency, etc. to optimize the performance, resistivity, and / or other properties of the metal electrodes.

[0139] In some embodiments described herein, low energy pulses are used to remove the volatiles in metal inks at a slower rate, preventing damage to the metal electrode. This photonic drying process saves time and energy relative to thermal drying approaches. For example, photonic drying often takes about 5 minutes to complete (e.g., when photonic drying is conducted for about 600 pulses at a frequency of about 2 hertz). By contrast, thermal drying often takes about 20 minutes or longer. Photonic drying processes also limit thermal exposure to sensitive components on the manufactured part. The use of photonic drying may also remove the need for any thermal processing resulting in less equipment needed in a manufacturing line.

[0140] In some embodiments, photonic drying and photonic sintering may be performed as a single process operation to avoid the need for thermal conditioning of metal electrodes. Photonic drying and photonic sintering may be performed by the same photonic device in some embodiments. However, in other embodiments, photonic drying and photonic sintering may be performed by two different photonic devices.

[0141] In some embodiments, metal electrodes may be deposited to repair damaged metal electrodes within a damaged assembly. Metal electrodes may be deposited individually, and these metal electrodes may be wrap-around metal electrodes. Metal electrodes may be formed using various printing technologies. These technologies include aerosol jetting, ink jetting, spray coating, etc. Printing may involve singulating components such as display tiles, sizing and shaping of display tiles, edge preparation, metal electrode printing, and the application of a protective coating. Various printing technologies described herein may be configured to print or repair individual metal electrodes, making the printing technologies beneficial for use in repairing damaged metal electrodes. By repairing these metal electrodes, open circuits may be avoided, and the high resistance of electrical lines may be avoided as well in some embodiments. The ability to print individual metal electrodes may drastically improve yield, resulting in significant cost savings and reduced defects in displays — with other approaches, displays with defects may need to be disassembled and remade until the defects are corrected.Metal electrodes may be deposited using approaches described herein on a variety of substrate materials, and metal electrodes may comprise gold, titanium, copper, silver, indium tin oxide, molybdenum, or aluminum material in some embodiments.

[0142] FIG. 11 A illustrates an example damaged assembly 1130 with gaps 1132B-1132E where metal electrodes are damaged. In FIG. 11 A, a first side 1101 A of a substrate 1126 is illustrated, and several electrically conductive lines are positioned on the first side 1101 A of the substrate 1126. These electrically conductive lines include a first electrically conductive line 1122A, a second electrically conductive line 1122B, a third electrically conductive line 1122C, a fourth electrically conductive line 1122D, a fifth electrically conductive line 1122E, and a sixth electrically conductive line 1122F.

[0143] Electrically conductive lines extend proximate to the edge 1135 of the first side 1101 A, but a gap remains between each of the electrically conductive lines 1122A-1122F and the edge 1135. For example, a first gap 1132A is positioned between the first electrically conductive line 1122A and the edge 1135, a second gap 1132B is positioned between the second electrically conductive line 1122B and the edge 1135, a third gap 1132C is positioned between the third electrically conductive line 1122C and the edge 1135, a fourth gap 1132D is positioned between the fourth electrically conductive line 1122D and the edge 1135, a fifth gap 1132E is positioned between the fifth electrically conductive line 1122E and the edge 1135, and a sixth gap 1132F is positioned between the sixth electrically conductive line 1122F and the edge 1135.

[0144] Metal electrodes extend in some of the gaps, but the metal electrodes are damaged in other gaps. As used herein, damaged metal electrodes may include metal electrodes that are incomplete or missing entirely. A first metal electrode 1112A extends from the first electrically conductive line 1122A to the edge 1135, and a second metal electrode 1112B extends from the sixth electrically conductive line 1122F to the edge 1135. However, the metal electrodes are each damaged at the second gap 1132B, the third gap 1132C, the fourth gap 1132D, and the fifth gap 1132E. Contamination 1133 from damaged metal electrodes are also illustrated at the second metal electrode 1112B, the third metal electrode 1112C, the fourth metal electrode 1112D, and the fifth metal electrode 1112E. In some cases, the metal electrodes may be missing entirely from certain gaps.

[0145] FIG. 11B illustrates the damaged assembly of FIG. 11A after it has been repaired to form a repaired assembly 1130A. In the repaired assembly 1130A, deposited metal electrodes are deposited at each of the gaps 1132A-1132F to repair any positions where metalelectrodes are damaged. For example, a first deposited metal electrode 1134A is positioned at the first gap 1132A between the first electrically conductive line 1122A and the edge 1135, a second deposited metal electrode 1134B is positioned at the second gap 1132B between the second electrically conductive line 1122B and the edge 1135, a third deposited metal electrode 1134C is positioned at the third gap 1132C between the third electrically conductive line 1122C and the edge 1135, a fourth deposited metal electrode 1134D is positioned at the fourth gap 1132D between the fourth electrically conductive line 1122D and the edge 1135, a fifth deposited metal electrode 1134E is positioned at the fifth gap 1132E between the fifth electrically conductive line 1122E and the edge 1135, and a sixth deposited metal electrode 1134F is positioned at the sixth gap 1132F between the sixth electrically conductive line 1122F and the edge 1135.

[0146] Metal electrodes may be printed with varying sizes and shapes. For example, the width of metal electrodes may be varied, the length of metal electrodes may be varied, the thickness of metal electrodes may be varied, and the pitch between metal electrodes may be varied. Repaired metal electrodes may generally be positioned on any side of a substrate.

[0147] Even where existing metal electrodes are complete and not damaged, deposited metal electrodes may still be deposited on these existing metal electrodes to ensure additional reliability. For example, in the repaired assembly 1130A, the first deposited metal electrode 1134A may be positioned over the first metal electrode 1112A (see FIG. 11 A) even though the first metal electrode 1112A is not damaged, and a sixth deposited metal electrode 1134F may be positioned over the second metal electrode 1112B (see FIG. 11 A) even though the second metal electrode 1112B is not damaged. In some embodiments, deposited metal electrodes may be dried and then sintered. Drying of the deposited metal electrodes may be performed through photonic drying in some embodiments, but drying may be performed thermally in other embodiments. Furthermore, sintering of deposited metal electrodes may be performed through photonic sintering in some embodiments, but sintering may be performed thermally in other embodiments.

[0148] While FIG. 1 IB illustrates metal electrodes extending from conductive lines to an edge, the metal electrodes may also extend further along additional side surfaces of a substrate. For example, FIG. 12A illustrates an example damaged assembly with areas where existing metal electrodes are damaged, and FIG. 12B illustrates deposited metal electrodes being deposited to extend further along additional side surfaces of a substrate, with the deposited metal electrodes being used to repair the damaged assembly.

[0149] The damaged assembly 1230 of FIG. 12A comprises a substrate 1226. This substrate 1226 may comprise glass material in some embodiments. The substrate 1226 defines a side 1201C, and this side 1201C may extend in a plane that is parallel to the Y-Z plane. This side 1201C includes a first edge 1235 A and a second edge 1235B. The damaged assembly 1230 includes electrically conductive lines 1222A-1222E on one side of the substrate 1226. As illustrated, some existing metal electrodes extend all the way from the first edge 1235A to the second edge 1235B. For example, metal electrodes 1212A-1212C each extend all the way from one side, around the first edge 1235A, around the second edge 1235B, and to the other side so that these metal electrodes 1212A-1212C wrap around the substrate 1226. The first metal electrode 1212A is connected to the first electrically conductive line 1222A, the second metal electrode 1212B is connected to the second electrically conductive line 1222B, and the third metal electrode 1212C is connected to the fifth electrically conductive line 1222E. However, in the region 1232, metal electrodes are missing altogether so that there are no metal electrodes connected to the third electrically conductive line 1222C or the fourth electrically conductive line 1222D.

[0150] FIG. 12B illustrates the damaged assembly of FIG. 12A after it has been repaired to form a repaired assembly 1230 A. As illustrated, deposited metal electrodes may be deposited that extend from the first edge 1235 A to the second edge 1235B. Deposited metal electrodes 1234A-1234E are each illustrated in FIG. 12B. The third deposited metal electrode 1234C and the fourth deposited metal electrode 1234D are positioned in the area 1232 of the damaged assembly 1230 where existing metal electrodes were missing altogether, and the first deposited metal electrodes 1234A, the second deposited metal electrode 1234B, and the fifth deposited metal electrode 1234E are each positioned at other locations where existing metal electrodes were previously included. In some embodiments, deposited metal electrodes may be dried and then sintered. Drying of the deposited metal electrodes may be performed through photonic drying in some embodiments, but drying may be performed thermally in other embodiments. Also, sintering of deposited metal electrodes may be performed through photonic sintering in some embodiments, but sintering may be performed thermally in other embodiments.

[0151] In order to individually deposit metal electrodes, aerosol jet printing may be used. FIG. 13 is a schematic view of an aerosol jet printer 1362, with the aerosol jet printer 1362 configured to print a metal electrode 1312 on a substrate 1326. The aerosol jet printer 1362 comprises a nozzle 1363 and a container 1370. Carrier gas 1374 may be introduced to the container 1370 and mixed with the metal ink 1372 within the container 1370. In someembodiments, the carrier gas 1374 may be nitrogen, but a wide variety of gases may be used for the carrier gas 1374. A mixture of the carrier gas 1374 and the metal ink 1372 may exit the container 1370 and enter into the channel 1368.

[0152] In the aerosol jet printer 1362, the mixture containing metal ink may move through the channel 1368 as indicated by the arrows towards the opening 1368 A. Additionally, a gas may move through the channel 1364 as indicated by the arrows towards the opening 1364 A, and the same gas may move through the channel 1366 as indicated by the arrows towards the opening 1366A. The gas travelling through the channels 1364, 1366 may be nitrogen in some embodiments, but a wide variety of other gases may be utilized. Upon the gases and the mixture exiting their respective openings 1364 A, 1366 A, 1368 A, the gases may tend to focus the mixture towards a small target area.

[0153] Using the aerosol jet printer 1362, the mixture comprising metal ink may be accurately deposited on the substrate 1326 or on the metal electrode 1312. The aerosol jet printer 1362 may print metal electrodes or repair damaged metal electrodes one by one until the assembly 1328 is completed or fully repaired. Metal inks may be particle based inks, reactive inks, blends of particle based inks and reactive inks, or multi-layer inks in some embodiments. In some embodiments, metal electrodes may be printed using other approaches such as ink-jetting, spray coating, pad printing, gravure printing, physical vapor deposition (PVD), chemical vapor deposition (CVD), electroplating, or other deposition methods. The assembly 1328 may be similar to the assembly 528 of FIGS. 5A-5C in some embodiments. Once the metal ink is deposited on the assembly 1328 to form the metal electrode 1312, the metal electrode 1312 may be dried and / or sintered as discussed herein, and this drying and sintering may be done photonically in some embodiments.

[0154] Methods of repairing open circuit metal electrodes are also contemplated. One example method 1400 for assembling and preparing a metal electrode is illustrated in FIG. 14. At operation 1402 of the method 1400, one or more locations are identified at the surface of the substrate where an existing metal electrode is damaged. Damaged metal electrode(s) may be caused by incomplete deposition, over etching, handling damage, etc. Damaged metal electrode(s) may be identified by manual or automated optical inspection in some embodiments. Additionally or alternatively, damaged metal electrode(s) may be identified through electrical measurements (e.g., measuring current or other electrical properties for electricity flowing through the metal electrode(s)). The repair location(s) may also be identified in-line with the printing system through optical microscopy.

[0155] At operation 1404, the underlying substrate and / or the damaged metal electrodes may optionally be pretreated at the defect site(s). Pretreatment of the surface may be performed prior to deposition of a repair metal electrode to improve adhesion of the repair metal electrode and / or to reduce contact resistance between the repaired metal electrode and the damaged metal electrode. This pretreatment may optionally be accomplished by exposing a buried layer in the damaged metal electrodes. For example, where a stack comprises a titanium outer layer and an intermediate layer of copper underneath the titanium outer layer, pretreatment may be used to remove titanium from the outer layer so that a repaired metal electrode may form a connection with the intermediate copper layer, and this may be beneficial since the titanium layer may rapidly oxidize under ambient conditions. Pretreatment may remove an insulating oxide layer or other contamination from the existing damaged metal electrode where electrical connection is being made with the damaged metal electrode. Additionally or alternatively, pretreatment may remove debris. Pretreatment may be performed near-line prior to the repair printing, or the pretreatment equipment may be installed inline to pretreat and / or repair the metal electrode(s) in series.

[0156] Pretreatment may be completed in a variety of ways. Pretreatment may be performed through localized chemical treatment, which may be accomplished by wet etching, dry etching, and chemical reduction. Pretreatment may also be accomplished through localized plasma treatment. Laser ablation is another approach that may be used to remove surface oxidation, surface debris, and / or contamination from damaged metal electrodes. Laser ablation may also be used to expose an underlying substrate material. Mechanical abrasion is another approach that may be used to remove surface debris and / or damaged metal electrodes. By performing pretreatment, the performance of the resulting assembly and metal electrodes may be improved.

[0157] At operation 1406, a metal electrode is printed to repair the open circuit metal electrode. In some embodiments, printing may be performed through aerosol jet printing. However, printing may also be accomplished by pad printing, gravure printing, physical vapor deposition (PVD), chemical vapor deposition (CVD), electroplating, or other deposition methods. Printing may be used to deposit a reactive metal ink, a nanoparticle metal ink, or a combination of the two to generate a repaired metal electrode. In some embodiments, metal electrodes may be printed in an inert environment to avoid substrate oxidation when necessary. However, in other embodiments, metal electrodes may be printed under ambient conditions. Insome embodiments, metal electrodes may be printed one at a time using aerosol jet printing or other techniques.

[0158] At operation 1408, repaired metal electrode(s) are dried. Drying may remove a volatile component from the repaired metal electrode. The repaired metal electrode(s) may be photonically dried in some embodiments, and photonic drying may be performed using a photonic device similar to those described herein. A temperature at the substrate may remain below about 100 degrees Celsius during photonic drying.

[0159] At operation 1410, the repaired metal electrode(s) are sintered. The repaired metal electrode(s) may be photonically sintered in some embodiments, and photonic sintering may be performed using a photonic device similar to those described herein. A temperature at the substrate may remain below about 100 degrees Celsius during photonic sintering.

[0160] Various photonic devices and approaches for photonic drying and photonic sintering are used. However, in some embodiments, photonic devices may be used to perform one of drying or sintering, and thermal heating devices may be used to perform the other task. As an even further alternative, in some embodiments, repair metal electrodes may be positioned and then thermally dried and / or thermally sintered.

[0161] FIG. 15 illustrates another method 1500 for assembling and preparing a metal electrode using thermal techniques. At operation 1502, ink is directed onto a substrate. The ink may be a particle based ink, a reactive ink, a blend of particle based ink and reactive ink, a multilayer ink, or some other type of ink. The ink may comprise various types of metals, including but not limited to gold, silver, copper, titanium, indium tin oxide, molybdenum, or aluminum. Ink may be directed using printing technologies such as aerosol jet printing, spray coating, or other approaches. At operation 1504, the ink is heated. Electrodes may be thermally heated at elevated temperatures of about 100 degrees Celsius to about 250 degrees Celsius in some embodiments to sinter metal particles and to provide an electrically conductive path in the metal electrode. The heating performed at operation 1504 may be completed to thermally dry and / or to thermally sinter the ink. At operation 1506, protective coating is added to the ink and / or the substrate. The protective coating may include a polymer coating in some embodiments, and the protective coating may provide mechanical protection for the electrode and may provide optical properties that enable an invisible tiled edge.

[0162] An example method 1600 for applying a ramped intensity profile is illustrated in FIG. 16. In some embodiments, the method 1600 may be performed using a photonic device to sinter a metal electrode, with the photonic device being configured to generate pulses ofphotonic energy. However, the method 1600 may be utilized by other devices to sinter or dry a metal electrode. For example, a ramped intensity profile may be applied using a thermal sintering device, using a laser sintering device comprising a laser, an infrared sintering device comprising an infrared lamp, etc. The method 1600 may be utilized to apply energy to a metal electrode of a display. For example, the method 1600 may be used to apply energy to a wraparound metal electrode that extends from a first side of a substrate in the display to a second side of the substrate.

[0163] At operation 1602, a substrate and a metal electrode may be provided, and the metal electrode may be positioned relative to the substrate. The substrate may comprise a first surface on a first side and a second surface on a second side. In some embodiments, the first surface and the second surface may be opposite to each other so that they face in opposite directions. However, in other embodiments, the first surface may extend in a plane that is offset from the second surface by about ninety degrees or by some other angle. The first surface and the second surface may converge at an edge in some embodiments.

[0164] The metal electrode may be positioned relative to the substrate so that the metal electrode extends from the first surface around an edge and to the second surface. In some embodiments, the metal electrode may be positioned using aerosol jet printing, but other techniques may be used such as ink-jetting, spray coating, pad printing, gravure printing, physical vapor deposition (PVD), chemical vapor deposition (CVD), or electroplating.

[0165] At operation 1603, a photonic device may be positioned relative to the metal electrode. The photonic device may be activated to dry the metal electrode by removing a volatile component from the metal electrode. The photonic device may be similar to the photonic devices described herein. The volatile component may be at least one of the carrier solvents or liquids or any of the low molecular weight byproducts from the reactive metal inks. During photonic drying, solvents and reducing agents are examples of volatile components that may be removed. In some embodiments, the volatile component may include water, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, glycerol, decane, or other materials. A temperature at the substrate may remain below about 100 degrees Celsius when the photonic device is in an activated state. During drying, the photonic device may be configured to be operate at a frequency of about 2 hertz and at a power level of about 3 kilowatts per centimeter squared. In some embodiments, two or more photonic devices may be positioned relative to the metal electrode at operation 1603, and the photonic devices may be activated to dry one or more metal electrodes byremoving volatile components from the metal electrode(s). Where multiple photonic devices are used, they may be activated simultaneously in some embodiments so that photonic drying occurs at the same time. Alternatively, photonic devices may be activated one at a time to conduct photonic drying. Multiple photonic devices may be utilized to target different locations on metal electrode(s), photonic devices may be oriented at different angles to target a location on a metal electrode from different angles. In some embodiments, a photonic device may be repositioned relative to the metal electrode so that the photonic device targets a different portion of the metal electrode or so that the photonic device targets a same location on the metal electrode from a different angle. Alternatively, the metal electrode may be repositioned relative to the photonic device.

[0166] At operation 1604, one or more sintering devices may be provided and positioned relative to the metal electrode. The sintering device(s) may be photonic devices in some embodiments and may comprise a lamp configured to generate photonic energy. In some embodiments, the sintering device(s) used in operation 1604 may be the same photonic devices used in operation 1603. The sintering device(s) may each comprise a mask that includes a wall defining a slot therein, and the mask may be configured to allow photonic energy to pass through the slot to generate emitted energy. The sintering device(s) may also be positioned relative to the metal electrode so that the slot is positioned relative to the metal electrode.

[0167] At operation 1606, the sintering device(s) may be activated and the generation of a first set of one or more pulses is caused. In some embodiments, photonic sintering devices may be used and may be configured to operate at a frequency of about 0.5 hertz and a power level of between about 4.2 kilowatts per centimeter squared and about 7.8 kilowatts per centimeter squared, but photonic sintering devices may also be configured to operate at different frequencies and at different power levels. At operation 1608, the generation of a second set of one or more pulses is caused, with the second set of pulse(s) being generated after the first set of one or more pulse(s). The second set of pulse(s) may have a different intensity from the first set of pulse(s) in some way. In some embodiments, the second set of one or more pulses has a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses. In some embodiments, the second set of one or more pulses has a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses. In some embodiments, the second set of one or more pulses has a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses. In some embodiments, the second set of one or more pulses has a second voltagelevel that is different relative to a first voltage level applied for the first set of one or more pulses. In some embodiments, the second set of one or more pulses has a second power level that is different relative to a first power level applied for the first set of one or more pulses.

[0168] In some embodiments, the second set of one or more pulses may have an increased intensity relative to the first set of pulse(s). For example, the second set of pulse(s) may have a second number of pulses that is increased relative to a first number of pulses in the first set of pulse(s). Alternatively, the second set of pulse(s) may have a second frequency of pulses that is increased relative to a first frequency of pulses in the first set of pulse(s). In some embodiments, the second set of pulse(s) may have a second duration of pulses that is increased relative to a first duration of pulses in the first set of pulse(s). In some embodiments, the second set of pulse(s) may have a second voltage level that is increased relative to a first voltage level applied for the first set of pulse(s). In some embodiments, the second set of pulse(s) may have a second power level that is increased relative to a first power level applied for the first set of pulse(s).

[0169] At operation 1610, the generation of a third set of one or more pulses is caused. In some embodiments, the third set of pulse(s) may be identical to the second set of pulse(s). However, in other embodiments, the third set of pulse(s) may be increased in intensity relative to the second set of pulse(s). The intensity may be increased using approaches described herein. Alternatively, the third set of pulse(s) may be decreased in intensity relative to the second set of pulse(s). In some embodiments, a temperature at the substrate may remain below about 100 degrees Celsius when the photonic sintering device is in an activated state. At operation 1612, a protective coating may be applied around material that is sintered in previous operations.

[0170] The methods 1400, 1500, 1600 illustrated in the flow charts of FIGS. 14-16 are provided merely as examples and are merely being provided for purposes of explanation. Various operations in these methods may be omitted in some embodiments. Additionally or alternatively, the operations in these methods may be performed in different orders or certain operations may be performed simultaneously. Additionally, additional operations may be added to the methods, and the methods 1400, 1500, 1600 may be combined together in some embodiments.CONCLUSION

[0171] Many modifications and other embodiments set forth herein will come to mind to one skilled in the art to which these embodiments pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to beunderstood that the embodiments are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the invention. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and / or functions, it should be appreciated that different combinations of elements and / or functions may be provided by alternative embodiments without departing from the scope of the invention. In this regard, for example, different combinations of elements and / or functions than those explicitly described above are also contemplated within the scope of the invention. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

WHAT IS CLAIMED IS:

1. A system for photonic sintering of a metal electrode, the system comprising: a display comprising a substrate comprising a first side and a second side, the metal electrode extending from the first side to the second side; and a photonic device for sintering the metal electrode, the photonic device comprising: a lamp configured to generate photonic energy and a mask positioned between the metal electrode and the lamp, the mask comprising a slot and configured to allow a portion of the photonic energy from the lamp to pass through the slot toward the metal electrode.

2. The system of claim 1, wherein the display comprises a component having a high optical density, and the mask is configured to prevent the photonic energy from the lamp from extending toward the component.

3. The system of claim 2, wherein the component is a thin film transistor.

4. The system of any of claims 1-3, further comprising: a second photonic device for sintering the metal electrode, the second photonic device comprising: a second lamp configured to generate photonic energy; a second mask comprising a second slot and configured to allow a portion of the photonic energy from the second lamp to pass through the second slot; and wherein the photonic device and the second photonic device target different locations on the metal electrode.

5. The system of claim 4, wherein the photonic device and the second photonic device are positioned in different orientations relative to the substrate.

6. The system of any of claims 1-5, wherein the metal electrode extends from the first side around at least one edge to the second side.

7. The system of any of claims 1-6, wherein the slot comprises a width that is approximately equal to a width of the metal electrode.

8. The system of any of claims 1-7, wherein at least one of the metal electrode or the photonic device is configured to be repositioned relative to the other.

9. The system of any of claims 1-8, wherein the photonic device further comprises at least one of an optical lens or a mirror, the optical lens or the mirror configured to be adjusted to alter properties of photonic energy generated by the photonic device.

10. The system of any of claims 1-9, wherein a temperature at the substrate remains below about 100 degrees Celsius when the photonic device is activated.

11. The system of any of claims 1-10, wherein: the photonic device is configured to photonically dry a target material in less time than a thermal drying device; or the photonic device is configured to photonically sinter a target material in less time than a thermal sintering device.

12. The system of any of claims 1-11, wherein the photonic device is configured to generate a first set of one or more pulses of photonic energy toward the metal electrode, a second set of one or more pulses of photonic energy toward the metal electrode after generating the first set of one or more pulses, and the second set of one or more pulses of photonic energy has an increased intensity relative to the first set of one or more pulses of photonic energy.

13. The system of claim 12, wherein the second set of one or more pulses has at least one of: a second number of pulses that is different relative to a first number of pulses in the first set of one or more pulses; a second frequency of pulses that is different relative to a first frequency of pulses in the first set of one or more pulses;a second duration of pulses that is different relative to a first duration of pulses in the first set of one or more pulses; a second voltage level that is different relative to a first voltage level applied for the first set of one or more pulses; or a second power level that is different relative to a first power level applied for the first set of one or more pulses.

14. A sintering device for sintering a metal electrode, the sintering device comprising: a lamp configured to generate photonic energy; and a mask comprising a slot, the mask configured to allow a portion of the photonic energy from the lamp to pass through the slot towards the metal electrode to sinter the metal electrode.

15. The sintering device of claim 14, wherein the metal electrode is on an assembly comprising the metal electrode and a substrate, and wherein the substrate has a lower optical density relative to the metal electrode.

16. The sintering device of claim 15, wherein the mask is configured to shield other components having an optical density that is higher than the optical density of the substrate from the photonic energy.

17. The sintering device of claim 16, wherein the substrate is exposed to a maximum temperature of less than about 100 degrees Celsius.

18. The sintering device of claim 17, wherein the metal electrode is a wrap-around metal electrode extending from a first side of the substrate to a second side of the substrate.

19. The sintering device of claim 18, wherein the assembly comprises a display, the display being at least one of a borderless display, a bezel free display, or a tiled display.

20. The sintering device of any of claims 14-19, wherein the slot comprises a circular shape, an oval shape, a rounded shape, a rectangular shape, a triangular shape, a polygonal shape, or an asymmetrical shape.

21. The sintering device of any of claims 14-20, wherein the slot comprises a cross- sectional area between about 1 square centimeter to about 10 square centimeters.

22. A method for using a sintering device, the method comprising: positioning a metal electrode on a substrate comprising a first side and a second side so that the metal electrode extends from the first side to the second side; positioning a sintering device relative to the metal electrode, the sintering device comprising a lamp configured to generate photonic energy and a mask comprising a slot, the mask configured to allow a portion of the photonic energy from the lamp to pass through the slot toward the metal electrode; and activating the sintering device to generate the photonic energy.

23. The method of claim 22, wherein the positioning the metal electrode comprises depositing the metal electrode using aerosol jetting, ink-jetting, or spray coating.

24. A display made by the method of claim 22.

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