Patent Publication Number: US-2021175219-A1

Title: Display area having tiles with improved edge strength and methods of making the same

Description:
FIELD 
     This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application Ser. No. 62/597111 filed on Dec. 11, 2017, the content of which is relied upon and incorporated herein by reference in its entirety. 
     The present disclosure relates generally to a display area comprising an array of tiles and more particularly, to a display area comprising an array of tiles having improved edge strength and methods of making the same. 
     BACKGROUND 
     Display technologies are emerging that benefit from tiling substrates, such as glass substrates, into an array or matrix to form a display larger than the individual substrate tiles. Such technologies include MiroLED. MicroLED can exhibit several advantages over alternative technologies, such as higher brightness, lower power consumption, higher contrast, and faster response. However, due to transfer head sizes and other limitations, the substrates to which MicroLEDs transfer is generally much smaller than the desired final display area, hence, the tiling of the substrates into an array or matrix to form a larger display. Under such conditions, the edge strength of the individual substrate tiles and minimizing the visibility of seams between adjacent tiles are important design considerations. 
     SUMMARY 
     Embodiments disclosed herein include a method for making a display area. The method includes assembling a plurality of glass tiles into an array, wherein each of the plurality of glass tiles in the array is adjacent to at least one other of the plurality of glass tiles in the array. Prior to assembling a glass tile into the array, an edge treatment is performed on the glass tile, the edge treatment increasing an edge strength of the glass tile, as measured by the four point bend test, to at least about 200 MPa. 
     Embodiments disclosed herein also include a method for making a glass tile that includes performing an edge treatment on the glass tile. The edge treatment increases an edge strength of the glass tile, as measured by the four point bend test, to at least about 200 MPa. 
     Embodiments disclosed herein also include a display area that includes an array of glass tiles, wherein each of glass tiles in the array is adjacent to at least one other of glass tiles in the array. Each of the glass tiles in the array has an edge strength, as measured by the four point bend test, of at least about 200 MPa. 
     Additional features and advantages of the embodiments disclosed herein will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the disclosed embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings. 
     It is to be understood that both the foregoing general description and the following detailed description present embodiments intended to provide an overview or framework for understanding the nature and character of the claimed embodiments. The accompanying drawings are included to provide further understanding, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the disclosure, and together with the description serve to explain the principles and operations thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of an example fusion down draw glass making apparatus and process; 
         FIG. 2  is an perspective view of a glass tile; 
         FIG. 3  is a perspective view of at least a portion of a beveling process of an edge surface of a glass tile; 
         FIG. 4  is a perspective view of at least a portion of an edge treatment process with a plasma jet; 
         FIG. 5  is a schematic front view of a portion of an edge of an exemplary glass tile prior to an edge treatment process with a plasma jet; 
         FIG. 6  is a schematic front view of a portion of an edge of an exemplary glass tile subsequent to an edge treatment process with a plasma jet; 
         FIG. 7  is a schematic side view of an edge of an exemplary glass tile having a protective material on an edge surface and portions of first and second major surfaces adjacent to the edge surface; and 
         FIG. 8  is a perspective view of a glass tile having a protective material on its edge surfaces and portions of first and second major surfaces adjacent to the edge surfaces; 
         FIG. 9  is a schematic front view of a display area having an array of glass tiles, each glass tile in the array having a protective material on its edge surfaces and portions of first and second major surfaces adjacent to the edge surfaces; 
         FIG. 10  is an enlarged, schematic front view of a portion of a glass tile including a plurality of pixels; and 
         FIG. 11  is a cross-sectional view of a pixel in the plurality of pixels shown in  FIG. 10  including at least one microLED. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the present preferred embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts. However, this disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. 
     Ranges can be expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, for example by use of the antecedent “about,” it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. 
     Directional terms as used herein—for example up, down, right, left, front, back, top, bottom—are made only with reference to the figures as drawn and are not intended to imply absolute orientation. 
     Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order, nor that with any apparatus specific orientations be required. Accordingly, where a method claim does not actually recite an order to be followed by its steps, or that any apparatus claim does not actually recite an order or orientation to individual components, or it is not otherwise specifically stated in the claims or description that the steps are to be limited to a specific order, or that a specific order or orientation to components of an apparatus is not recited, it is in no way intended that an order or orientation be inferred, in any respect. This holds for any possible non-express basis for interpretation, including: matters of logic with respect to arrangement of steps, operational flow, order of components, or orientation of components; plain meaning derived from grammatical organization or punctuation, and; the number or type of embodiments described in the specification. 
     As used herein, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a” component includes aspects having two or more such components, unless the context clearly indicates otherwise. 
     As used herein, the term “plasma” refers to an ionized gas comprising positive ions and free electrons. 
     As used herein, the term “atmospheric pressure plasma jet” refers to a flow of plasma discharged from an aperture, wherein the plasma pressure approximately matches that of the surrounding atmosphere, including conditions wherein the plasma pressure is between 90% and 110% of 101.325 kilopascals (standard atmospheric pressure). 
     As used herein, the term “particles” refers to any type of particles that can be present on a surface, such as glass particles and dust particles. 
     As used herein, the term, “edge strength, as measured by the four point bend test”, refers to edge strength at which 10% of samples would be expected to fail using the glass flexure fixture four point test set forth in JIS R1601. 
     As used here, the term “adjacent” refers to immediate proximity with or without physical contact. 
     Shown in  FIG. 1  is an exemplary glass manufacturing apparatus  10 . In some examples, the glass manufacturing apparatus  10  can comprise a glass melting furnace  12  that can include a melting vessel  14 . In addition to melting vessel  14 , glass melting furnace  12  can optionally include one or more additional components such as heating elements (e.g., combustion burners or electrodes) that heat raw materials and convert the raw materials into molten glass. In further examples, glass melting furnace  12  may include thermal management devices (e.g., insulation components) that reduce heat lost from a vicinity of the melting vessel. In still further examples, glass melting furnace  12  may include electronic devices and/or electromechanical devices that facilitate melting of the raw materials into a glass melt. Still further, glass melting furnace  12  may include support structures (e.g., support chassis, support member, etc.) or other components. 
     Glass melting vessel  14  is typically comprised of refractory material, such as a refractory ceramic material, for example a refractory ceramic material comprising alumina or zirconia. In some examples glass melting vessel  14  may be constructed from refractory ceramic bricks. Specific embodiments of glass melting vessel  14  will be described in more detail below. 
     In some examples, the glass melting furnace may be incorporated as a component of a glass manufacturing apparatus to fabricate a glass substrate, for example a glass ribbon of a continuous length. In some examples, the glass melting furnace of the disclosure may be incorporated as a component of a glass manufacturing apparatus comprising a slot draw apparatus, a float bath apparatus, a down-draw apparatus such as a fusion process, an up-draw apparatus, a press-rolling apparatus, a tube drawing apparatus or any other glass manufacturing apparatus that would benefit from the aspects disclosed herein. By way of example,  FIG. 1  schematically illustrates glass melting furnace  12  as a component of a fusion down-draw glass manufacturing apparatus  10  for fusion drawing a glass ribbon for subsequent processing into individual glass sheets. 
     The glass manufacturing apparatus  10  (e.g., fusion down-draw apparatus  10 ) can optionally include an upstream glass manufacturing apparatus  16  that is positioned upstream relative to glass melting vessel  14 . In some examples, a portion of, or the entire upstream glass manufacturing apparatus  16 , may be incorporated as part of the glass melting furnace  12 . 
     As shown in the illustrated example, the upstream glass manufacturing apparatus  16  can include a storage bin  18 , a raw material delivery device  20  and a motor  22  connected to the raw material delivery device. Storage bin  18  may be configured to store a quantity of raw materials  24  that can be fed into melting vessel  14  of glass melting furnace  12 , as indicated by arrow  26 . Raw materials  24  typically comprise one or more glass forming metal oxides and one or more modifying agents. In some examples, raw material delivery device  20  can be powered by motor  22  such that raw material delivery device  20  delivers a predetermined amount of raw materials  24  from the storage bin  18  to melting vessel  14 . In further examples, motor  22  can power raw material delivery device  20  to introduce raw materials  24  at a controlled rate based on a level of molten glass sensed downstream from melting vessel  14 . Raw materials  24  within melting vessel  14  can thereafter be heated to form molten glass  28 . 
     Glass manufacturing apparatus  10  can also optionally include a downstream glass manufacturing apparatus  30  positioned downstream relative to glass melting furnace  12 . In some examples, a portion of downstream glass manufacturing apparatus  30  may be incorporated as part of glass melting furnace  12 . In some instances, first connecting conduit  32  discussed below, or other portions of the downstream glass manufacturing apparatus  30 , may be incorporated as part of glass melting furnace  12 . Elements of the downstream glass manufacturing apparatus, including first connecting conduit  32 , may be formed from a precious metal. Suitable precious metals include platinum group metals selected from the group of metals consisting of platinum, iridium, rhodium, osmium, ruthenium and palladium, or alloys thereof. For example, downstream components of the glass manufacturing apparatus may be formed from a platinum-rhodium alloy including from about 70 to about 90% by weight platinum and about 10% to about 30% by weight rhodium. However, other suitable metals can include molybdenum, palladium, rhenium, tantalum, titanium, tungsten and alloys thereof. 
     Downstream glass manufacturing apparatus  30  can include a first conditioning (i.e., processing) vessel, such as fining vessel  34 , located downstream from melting vessel  14  and coupled to melting vessel  14  by way of the above-referenced first connecting conduit  32 . In some examples, molten glass  28  may be gravity fed from melting vessel  14  to fining vessel  34  by way of first connecting conduit  32 . For instance, gravity may cause molten glass  28  to pass through an interior pathway of first connecting conduit  32  from melting vessel  14  to fining vessel  34 . It should be understood, however, that other conditioning vessels may be positioned downstream of melting vessel  14 , for example between melting vessel  14  and fining vessel  34 . In some embodiments, a conditioning vessel may be employed between the melting vessel and the fining vessel wherein molten glass from a primary melting vessel is further heated to continue the melting process, or cooled to a temperature lower than the temperature of the molten glass in the melting vessel before entering the fining vessel. 
     Bubbles may be removed from molten glass  28  within fining vessel  34  by various techniques. For example, raw materials  24  may include multivalent compounds (i.e. fining agents) such as tin oxide that, when heated, undergo a chemical reduction reaction and release oxygen. Other suitable fining agents include without limitation arsenic, antimony, iron and cerium. Fining vessel  34  is heated to a temperature greater than the melting vessel temperature, thereby heating the molten glass and the fining agent. Oxygen bubbles produced by the temperature-induced chemical reduction of the fining agent(s) rise through the molten glass within the fining vessel, wherein gases in the molten glass produced in the melting furnace can diffuse or coalesce into the oxygen bubbles produced by the fining agent. The enlarged gas bubbles can then rise to a free surface of the molten glass in the fining vessel and thereafter be vented out of the fining vessel. The oxygen bubbles can further induce mechanical mixing of the molten glass in the fining vessel. 
     Downstream glass manufacturing apparatus  30  can further include another conditioning vessel such as a mixing vessel  36  for mixing the molten glass. Mixing vessel  36  may be located downstream from the fining vessel  34 . Mixing vessel  36  can be used to provide a homogenous glass melt composition, thereby reducing cords of chemical or thermal inhomogeneity that may otherwise exist within the fined molten glass exiting the fining vessel. As shown, fining vessel  34  may be coupled to mixing vessel  36  by way of a second connecting conduit  38 . In some examples, molten glass  28  may be gravity fed from the fining vessel  34  to mixing vessel  36  by way of second connecting conduit  38 . For instance, gravity may cause molten glass  28  to pass through an interior pathway of second connecting conduit  38  from fining vessel  34  to mixing vessel  36 . It should be noted that while mixing vessel  36  is shown downstream of fining vessel  34 , mixing vessel  36  may be positioned upstream from fining vessel  34 . In some embodiments, downstream glass manufacturing apparatus  30  may include multiple mixing vessels, for example a mixing vessel upstream from fining vessel  34  and a mixing vessel downstream from fining vessel  34 . These multiple mixing vessels may be of the same design, or they may be of different designs. 
     Downstream glass manufacturing apparatus  30  can further include another conditioning vessel such as delivery vessel  40  that may be located downstream from mixing vessel  36 . Delivery vessel  40  may condition molten glass  28  to be fed into a downstream forming device. For instance, delivery vessel  40  can act as an accumulator and/or flow controller to adjust and/or provide a consistent flow of molten glass  28  to forming body  42  by way of exit conduit  44 . As shown, mixing vessel  36  may be coupled to delivery vessel  40  by way of third connecting conduit  46 . In some examples, molten glass  28  may be gravity fed from mixing vessel  36  to delivery vessel  40  by way of third connecting conduit  46 . For instance, gravity may drive molten glass  28  through an interior pathway of third connecting conduit  46  from mixing vessel  36  to delivery vessel  40 . 
     Downstream glass manufacturing apparatus  30  can further include forming apparatus  48  comprising the above-referenced forming body  42  and inlet conduit  50 . Exit conduit  44  can be positioned to deliver molten glass  28  from delivery vessel  40  to inlet conduit  50  of forming apparatus  48 . For example in examples, exit conduit  44  may be nested within and spaced apart from an inner surface of inlet conduit  50 , thereby providing a free surface of molten glass positioned between the outer surface of exit conduit  44  and the inner surface of inlet conduit  50 . Forming body  42  in a fusion down draw glass making apparatus can comprise a trough  52  positioned in an upper surface of the forming body and converging forming surfaces  54  that converge in a draw direction along a bottom edge  56  of the forming body. Molten glass delivered to the forming body trough via delivery vessel  40 , exit conduit  44  and inlet conduit  50  overflows side walls of the trough and descends along the converging forming surfaces  54  as separate flows of molten glass. The separate flows of molten glass join below and along bottom edge  56  to produce a single ribbon of glass  58  that is drawn in a draw or flow direction  60  from bottom edge  56  by applying tension to the glass ribbon, such as by gravity, edge rolls  72  and pulling rolls  82 , to control the dimensions of the glass ribbon as the glass cools and a viscosity of the glass increases. Accordingly, glass ribbon  58  goes through a visco-elastic transition and acquires mechanical properties that give the glass ribbon  58  stable dimensional characteristics. Glass ribbon  58  may, in some embodiments, be separated into individual glass sheets  62  by a glass separation apparatus  100  in an elastic region of the glass ribbon. A robot  64  may then transfer the individual glass sheets  62  to a conveyor system using gripping tool  65 , whereupon the individual glass sheets may be further processed. 
     Glass sheets  62  may further be separated into individual glass tiles by one or more methods known to persons of ordinary skill in the art such as, for example, a mechanical cutting technique. Exemplary cutting techniques include, for example, use of a semiconductor dicing saw or a mechanical scribe. Glass sheets  63  may also be separated into individual glass tiles by other techniques, such as, for example, laser-based cutting and separation techniques. 
       FIG. 2  shows a perspective view of a glass tile  160  having a first major surface  162 , a second major surface  164  extending in a generally parallel direction to the first major surface (on the opposite side of the glass tile  160  as the first major surface) and an edge surface  166  extending between the first major surface and the second major surface and extending in a generally perpendicular direction to the first and second major surfaces  162 ,  164 . 
       FIG. 3  shows a perspective view of at least a portion of a beveling process of an edge surface  166  of a glass tile  160 . As shown in  FIG. 3 , beveling process includes applying a grinding wheel  200  to edge surface  166 , wherein the grinding wheel  200  moves relative to edge surface  166  in the direction indicated by arrow  300 . Beveling process may further include applying at least one polishing wheel (not shown) to edge surface  166 . Such beveling process can lead to the presence of numerous glass particles, as well as surface and sub-surface damage (i.e., irregular topography), on edge surface  166 . 
     Downstream processing of glass tile  160  may involve application of mechanical or chemical treatments on edge surfaces  166 , which can result in additional particle generation due to the presence of irregular edge surface topography. Such particles may migrate to at least one surface of glass tile  160 . Accordingly, embodiments disclosed herein include those in which irregular edge surface topography is removed, while at the same time removing and/or reducing edge particles present on the edge surfaces  166  as well as removing reaction by-products that may be formed upon removal of the irregular edge surface topography. 
       FIG. 4  shows a perspective view of at least a portion of a treatment process of an edge surface  166  of a glass tile  160  with a plasma jet  402 . As shown in  FIG. 4 , treatment process includes directing a flow of plasma, via plasma jet  402 , toward edge surface  166 , wherein plasma jet head  400  moves relative to edge surface  166  in the direction indicated by arrow  500 . In certain exemplary embodiments, plasma jet  402  comprises an atmospheric pressure plasma jet. 
     Plasma jet  402  can be directed toward edge surface  166  under a variety of processing parameters. In certain exemplary embodiments, plasma jet  402  can be generated at a power of at least about 300 watts, such as a power of at least about 500 watts, including a power of from about 300 watts to about 800 watts and further including a power of from about 500 watts to about 800 watts. 
     In certain exemplary embodiments, plasma jet  402  is generated via a direct current high voltage discharge that generates a pulsed electric arc, such as a voltage discharge of at least about 5 kV, such as from about 5 kV to about 15 kV. In certain exemplary embodiments, plasma jet 402 is generated at a frequency of at least about 10 kHz, such as from about 10 kHz to about 100 kHz. In certain exemplary embodiments, plasma jet can have a beam length of from about 5 millimeters to about 40 millimeters and a widest beam width of from about 3 millimeters to about 15 millimeters. 
     In certain exemplary embodiments, the distance between the portion of plasma jet head  400  that is closest to edge surface  166  and edge surface  166  (referred to herein as “gap distance”), is at least about 2 millimeters, such as at least about 3 millimeters, and further such as at least about 4 millimeters, and yet further such as at least about 5 millimeters, such as from about 2 millimeters to about 10 millimeters, including from about 5 millimeters to about 10 millimeters. 
     In certain exemplary embodiments, the speed of relative movement between plasma jet head  400  and edge surface  166  (referred to herein as “scan speed”) can range from about 1 millimeter per second to about 50 millimeters per second, such as from about 5 millimeters per second to about 25 millimeters per second, and further such as from about 10 millimeters per second to about 20 millimeters per second. 
     In certain exemplary embodiments, the number of times that the plasma jet head  400  moves relative to the entire length of edge surface  166  (referred to herein as “scan pass”) can be at least 1 pass, such as at least 2 passes, and further such as at least 3 passes, and yet further such as at least 4 passes, including from 1 pass to 10 passes, and further including from 2 passes to 6 passes. 
     In certain exemplary embodiments, the plasma comprises at least one component selected from the group consisting of nitrogen, argon, oxygen, hydrogen, and helium that is excited and at least partially converted to the plasma state. In certain exemplary embodiments, the plasma comprises at least one component selected from the group consisting of nitrogen, argon, and hydrogen, such as at least two components selected from the group consisting of nitrogen, argon, and hydrogen, and further such as embodiments in which the plasma comprises each of nitrogen, argon, and hydrogen. When the plasma comprises at least one of nitrogen, argon, and hydrogen, the nitrogen content can, for example, range from about 50 mol % to about 100 mol %, such as from about 60 mol % to about 90 mol %, the argon content can, for example, range from about 0 mol % to about 20 mol %, such as from about 5 mol % to about 15 mol %, and the hydrogen content can, for example, range from about 0 mol % to about 10 mol %, such as from about 1 mol % to about 5 mol %. 
     In certain exemplary embodiments, treatment process comprising directing a flow of plasma, via plasma jet  402 , toward edge surface  166 , can result in a substantial reduction of particle density on edge surface  166 , such as a particle density reduction of at least 1 order of magnitude, and further such as a particle density reduction of at least 2 orders of magnitude, and yet further such as a particle density reduction of at least 3 orders of magnitude. For example, directing a flow of plasma toward edge surface  166 , according to embodiments disclosed herein, can reduce a density of particles on edge surface  166  to less than about 40 per 0.1 square millimeter, such as less than about 30 per 0.1 square millimeter, and further such as less than about 20 per 0.1 square millimeter, and yet further such as less than about 10 per 0.1 square millimeter, including from about 0 to about 40 particles per 0.1 square millimeter, and further including from about 1 to about 30 particles per 0.1 square millimeter, and yet further from about 2 to about 20 particles per 0.1 square millimeter. 
     Embodiments disclosed herein include those in which plasma jet  402  is applied toward edge surface  166  after or in lieu of an edge beveling process, such as the exemplary edge beveling process shown in  FIG. 3 . For example, in certain exemplary embodiments, plasma jet  402  may be applied toward edge surface  166  of glass tile  160  immediately following separation of glass tile  160  from glass sheet  62 . Alternatively, subsequent processing steps, such as the exemplary edge beveling process shown in  FIG. 3 , may be applied to glass tile  160 , prior to application of plasma jet  402  toward edge surface  166  of glass tile  160 . 
       FIG. 5  is a schematic front view of a portion of an edge  166  of an exemplary glass tile  160  prior to an edge treatment process with a plasma jet. As shown in  FIG. 5 , irregular edge surface topography is shown as being magnified or exaggerated and includes crack feature  168  as well as adhered glass particles  170 . 
       FIG. 6  is a schematic front view of a portion of an edge  166  of an exemplary glass tile  160  subsequent to an edge treatment process with a plasma jet. As shown in  FIG. 6 , irregular edge surface topography, including crack feature  168  as well as adhered glass particles  170 , has been smoothed over. In addition, the intersection of edge  166  and first major surface  162  of glass tile  160  comprises a rounded corner  172 . 
     In certain exemplary embodiments, edge surface  166  may be heated, for example, by an electrical resistance heater or an induction heater, to a temperature of at least about 100° C., such as at least about 200° C., and further such as at least about 300° C., and yet further such as at least about 400° C., and still yet further such as at least about 500° C., including a temperature ranging from about 100° C. to about 600° C. prior to directing the flow of plasma toward the edge surface  166 . Exemplary embodiments also include those in which temperature of edge surface  166  is maintained in the above-referenced ranges for a period of time subsequent to directing a flow of plasma toward the edge surface  166 . Such heat treatment can potentially reduce edge tensile stress. 
       FIG. 7  is a schematic side view of an edge of an exemplary glass tile  160  having a protective material  174  on an edge surface  166  and portions of first major surface  162  and second major surface  164  adjacent to the edge surface  166 . While not limited to any particular amount of coverage, in certain exemplary embodiments protective material  174  may cover at least about 1% of first major surface  162  and second major surface  164 , such as from about 1% to about 10% of first major surface  162  and second major surface  164 , including from about 2% to about 5% of first major surface  162  and second major surface  164 . While  FIG. 7  shows protective material  174  on portions of first major surface  162  and second major surface  164 , it is to be understood that embodiments disclosed herein include those in which protective material  174  is only on edge surface  166 . 
     As shown in  FIG. 7 , protective material  174  on portions of first major surface  162  and second major surface  164  decreases in thickness between rounded corner  172  and portion of protective material on first major surface  162  and second major surface  164  that is furthest away from rounded corner  172 . While  FIG. 7  shows protective material  174  decreasing in thickness on first major surface  162  and second major surface  164 , it is to be understood that embodiments disclosed herein include those in which protective material  174  is of relatively constant thickness on first major surface  162  and second major surface  164 . The combination of rounded corners  172  and protective material  174  covering not only edge surface  166  but also at least a portion of first major surface  162  and second major surface  164  can enable glass tiles  160  with exceptional edge strength and resistance to cracking or chipping. 
     As shown in  FIG. 7 , protective material  174  is of relatively constant thickness on edge surface  166 . While not limited to any particular thickness, in certain exemplary embodiments protective material  174  covering edge surface  166  may have a thickness of at least about 1 micron, such as from about 1 micron to about 500 microns. In addition, protective material  174  covering at least a portion of first major surface  162  and second major surface  164  may have a thickness of at least about 1 micron, such as from about 1 micron to about 500 microns, including a thickness that decreases from between about 1 micron and about 500 microns near rounded corner  172  to less than about 0.1 microns on first major surface  162  and second major surface  164  that is furthest away from rounded corner  172 . 
     In certain exemplary embodiments, protective material  174  comprises a solution-based coating. The solution can include organic or inorganic (e.g., water-based) solvents and the solution-based coating can, for example, be selected from not only a solution but also at least one of a sol-gel, a dispersion, a suspension, and a slurry. When the solution-based coating comprises a sol-gel, the sol-gel can be thermally or UV-curable. Exemplary, solution-based coatings include polyimide (PI) and polydimethylsiloxane (PDMS). 
     The solution-based coating may be applied by any method known to persons having ordinary skill in the art, such as, for example, dipping, spraying, brushing, rolling, and vapor deposition. Following application, and depending on the type of coating applied, a drying technique known to persons of ordinary skill in the art, such as for example, convection drying or microwave drying, may be used. In certain exemplary embodiments, portion of glass tile  160  not intended to be covered by solution-based coating may be covered with a masking material that can be removed following application and curing and/or drying of protective material  174 . 
     In certain exemplary embodiments, protective material  174  comprises at least one inorganic material. Exemplary inorganic materials can include glass frit, such as a relatively transparent glass frit, and metal oxides such as silica (SiO 2 ), zinc oxide (ZnO), and tin oxide (SnO 2 ). While such materials may be applied in a solution-based coating, such as described above, they may be also applied according to other methods including, for example, by flame deposition. For example, when silica is applied via flame deposition, a silane precursor in a carrier gas, such as nitrogen, may react with oxygen in a flame to produce silica. And, in certain exemplary embodiments, such as when the protective material  174  comprises glass frit, the protective material may be applied using a pen-dispenser, which may, in certain exemplary embodiments, be followed by a thermal sintering or laser sealing process to fill any cracks and thereby further increase edge strength. 
     In exemplary embodiments, treatment processes as described herein, including directing a flow of plasma, via plasma jet  402 , toward edge surface  166  of a glass tile  160  and/or applying a protective material  174  on an edge surface  166  of the glass tile  160  can result in an edge strength as measured by the four point bend test, of at least about 200 MPa, such as at least about 250 MPa, and further such as at least about 300 MPa. For example, in certain embodiments, the distance of the extension direction of the edge between the first and second major surfaces (i.e., the thickness of glass tile  160 ) is less than or equal to about 0.5 millimeters and treatment processes as described herein can result in an edge strength, as measured by the four point bend test, of at least about 200 MPa, such as at least about 250 MPa, and further such as at least about 300 MPa. 
       FIG. 8  is a perspective view of a glass tile  160  having a protective material  174  on its edge surfaces  166  and portions of its first major surface  162  and second major surface  164  adjacent to its edge surfaces  166 .  FIG. 9  is a schematic front view of a display area  200  having an m×n array of glass tiles  160 , each glass tile  160  in the array having a protective material  174  on its edge surfaces and portions of first and second major surfaces adjacent to the edge surfaces. As shown in  FIG. 9 , a glass tile  160  is being added to the array  200 . In the array  200  of glass tiles  160  shown in  FIG. 9 , each of glass tiles  160  in the array  200  is adjacent to at least one other of the plurality of glass tiles  160  in the array  200 . While array  200  is shown as having a generally rectangular shape, it is understood that embodiments disclosed herein are not so limited and include a variety of shapes, sizes, and planarity including, but not limited to circular, elliptical, and other geometric and polygonal shapes. 
     In being adjacent to at least one other of the plurality of glass tiles  160  in the array  200 , each glass tile  160  in the array  200  may be in physical contact with at least one other glass tile  160  in the array  200 . For example, each glass tile  160  in the array  200  may be in physical contact with each glass tile in its immediate proximity. Each glass tile  160  may also be spaced a predetermined distance from glass tiles  160  in its immediate proximity, such as at least about 1 micron away from the next nearest glass tile  160 , including from about 1 micron to about 20 microns, such as from about 2 microns to about 10 microns away from the next nearest glass tile  160 . 
       FIG. 10  shows an enlarged, schematic front view of a portion of a glass tile  160  comprising a plurality of pixels  202 . The number of pixels  202  per glass tile  160  can vary depending on the application, which is dependent on pixel pitch (i.e., distance between immediately adjacent pixels) as well as the size of the glass tile  160 . 
       FIG. 11  shows a cross-sectional view of a pixel  202  in the plurality of pixels shown in  FIG. 10  including at least one microLED. Specifically,  FIG. 11  shows a pixel  202  comprising a substrate  204 , a glass or film  206  opposite the substrate  204 , and three microLEDs,  208   a,    208   b,  and  208   c,  each microLED with a corresponding electrode,  210   a ,  210   b,  and  210   c  to control the operation of the respective microLED. For example, in some embodiments, one of the microLEDs can include a red microLED, one of the microLEDs can include a green microLED, and one of the microLEDs can include a blue microLED. 
     While the above embodiments have been described with reference to a fusion down draw process, it is to be understood that such embodiments are also applicable to other glass forming processes, such as float processes, slot draw processes, up-draw processes, tube drawing processes, and press-rolling processes. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to embodiment of the present disclosure without departing from the spirit and scope of the disclosure. Thus it is intended that the present disclosure cover such modifications and variations provided they come within the scope of the appended claims and their equivalents.