PATENT DOCUMENT

Publication Number: US-9678540-B2
Application Number: US-201414512660-A
Country: US
Kind Code: B2

Title: Electronic component embedded in ceramic material

Abstract:
A ceramic material having an electronic component embedded therein, and more particularly to a sapphire surface having an electrically energized component embedded within. In some embodiments, the sapphire surface may take the form of a portion of a housing for an electronic device. Since sapphire may be substantially transparent, it may form a cover glass for a display within or forming part of the electronic device, as one example. The cover glass may be bonded, affixed, or otherwise attached to a remainder of the housing, thereby forming an enclosure for the electronic device.

Claims:
We claim: 
     
       1. An electronic device, comprising:
 a housing; 
 a display in the housing; 
 a cover glass affixed to the housing that covers the display, wherein the cover glass comprises a first transparent element and a second transparent element, wherein the first transparent element has a recess that is completely surrounded by a raised lip, and wherein the second transparent element fits within the recess; 
 a groove formed at an interface between the first and second transparent elements; 
 an electronic component held within the groove; and 
 an electronic circuit positioned below the cover glass. 
 
     
     
       2. The electronic device of  claim 1 , further comprising:
 at least one via in electrical communication with the electronic circuit and the electronic component, the via defining an electrical connection between the electronic circuit and the electronic component. 
 
     
     
       3. The electronic device of  claim 2 , wherein the via extends through a portion of the cover glass. 
     
     
       4. The electronic device of  claim 1 , wherein the first and second transparent elements are bonded together. 
     
     
       5. The electronic device of  claim 1 , further comprising a sensor disposed below the electronic circuit. 
     
     
       6. An electronic device, comprising:
 a housing; 
 a display in the housing; 
 a transparent element that covers the display and is affixed to the housing, wherein the transparent element has first and second opposing surfaces, wherein the first surface of the transparent element forms an exterior surface of the electronic device, and wherein a trench is formed in the second surface of the transparent element; 
 an antenna, wherein at least a portion of the antenna is formed in the trench; 
 a masking layer that is formed on the second surface of the transparent element in the trench, wherein the masking layer is interposed between the second surface of the transparent element and the antenna; 
 a touch-sensitive layer in the housing; 
 a near-field communication element positioned below the display; and 
 at least one electronic circuit within the housing, wherein the at last one electronic circuit is in electrical communication with the antenna. 
 
     
     
       7. The electronic device defined in  claim 6 , wherein the touch-sensitive layer is interposed between the display and the transparent element. 
     
     
       8. The electronic device defined in  claim 6 , wherein the touch-sensitive layer is formed separately from the transparent element. 
     
     
       9. The electronic device defined in  claim 6 , wherein the transparent element is formed from sapphire. 
     
     
       10. The electronic device defined in  claim 6 , wherein the masking layer masks the presence of the antenna. 
     
     
       11. The electronic device defined in  claim 6 , wherein the masking layer comprises at least one ink layer. 
     
     
       12. The electronic device defined in  claim 6 , wherein the display is interposed between the near-field communication element and the transparent element that covers the display. 
     
     
       13. The electronic device defined in  claim 6 , wherein the display overlaps the near-field communication element. 
     
     
       14. The electronic device defined in  claim 6 , further comprising:
 an optical sensor that receives light through the transparent element. 
 
     
     
       15. The electronic device defined in  claim 14 , wherein the display is interposed between the optical sensor and the transparent element. 
     
     
       16. The electronic device defined in  claim 15 , wherein the near-field communication element is interposed between the optical sensor and the transparent element. 
     
     
       17. The electronic device defined in  claim 6 , further comprising a shield interposed between the antenna and the near-field communication element.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a nonprovisional patent application of and claims the benefit to U.S. Provisional Patent Application No. 61/892,389, field Oct. 17, 2013 and titled “Electronic component Embedded in Ceramic Material,” the disclosure of which is hereby incorporated herein by reference in its entirety. This application is also a continuation-in-part patent application of U.S. patent application Ser. No. 14/033,981, filed Sep. 23, 2013 and titled “Electronic Component Embedded in Ceramic Material,” the disclosure of which is hereby incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     Embodiments described herein relate generally to ceramic materials having an electronic component embedded therein, and more particularly to electrically active components embedded in a ceramic surface defining a portion of an outer surface of an electronic device. 
     BACKGROUND 
     Electronic devices are ubiquitous in modern society. Examples include phones, tablet computing devices, personal computers, watches, glasses, fitness meters, earpieces, and so on. One thing is generally true of all electronic devices: each generation adds more functionality (and thus circuitry) than the last. As circuitry increases, available space decreases. 
     Eventually, even with the ongoing miniaturization in circuitry, a limit on physical space can be reached such that no more space is available to add any more electronic components. Likewise, even if space is available, cross-talk, interference and the like between closely-packed electronic components may cause erratic operation of overall failure. 
     Some electronic devices include a cover glass or other relatively hard, transparent element that covers a display. The cover glass typically is not used for anything other than protection of the display and to form part of the housing, or to be affixed to the housing. Thus, the space occupied by the cover glass may be considered wasted space from the point of view of attempting to maximize electronic circuitry within a given volume for an electronic device. 
     Further, some electronic devices use sapphire or other hard but brittle ceramics as a cover glass. Such cover glasses may be very resistant to scratches and damage, but may be difficult to cut, polish, grind, drill or otherwise shape or process due to their very hardness. 
     Thus, an improved ceramic material having an electronic component embedded therein may be useful. 
     SUMMARY OF THE DISCLOSURE 
     One embodiment described herein may take the form of an electronic device, including: a housing; a cover glass affixed to the housing; an electronic component embedded within the cover glass; an electronic circuit positioned below the cover glass; and a sensor positioned below the electronic circuit. The electronic device may also have a trench defined within the cover glass; the electronic component located within the trench; and a retention element occupying a remainder of the trench, thereby embedding the electronic component with the cover glass. 
     Another embodiment may take the form of an electronic device, comprising: a housing; a ceramic element affixed to the housing, the ceramic element defining a void; an electronic component affixed within the void; at least one electronic circuit within the housing and in electrical communication with the electronic component; and at least one sensor positioned below the at least one electronic circuit. 
     Other embodiments will be apparent to those skilled in the art upon reading the disclosure in its entirety. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  depicts a perspective view of a sample electronic device having an electronic component embedded in a ceramic material. 
         FIG. 2  is a cross-sectional view of the sample electronic device of  FIG. 1 , taken along line A-A of  FIG. 1 . 
         FIG. 3A  is an exploded view of the cover glass structure of  FIG. 2 , showing the electronic component and other elements. 
         FIG. 3B  is a cross-sectional view of a cover glass substrate, taken along line  3 B- 3 B of  FIG. 3A . 
         FIG. 4  is a cross-sectional view of another sample electronic device having an electronic component embedded in a ceramic material, similar to the view of  FIG. 2 . 
         FIG. 5A  is an exploded view of the cover glass structure of  FIG. 4 , showing the electronic component and other elements. 
         FIG. 5B  is a cross-sectional view of another sample cover glass substrate, taken along line  5 B- 5 B of  FIG. 5A . 
         FIG. 6  is a cross-sectional view of a third sample electronic device having an electronic component embedded in a ceramic material, similar to the view of  FIG. 2 . 
         FIG. 7  is a cross-sectional view of a fourth sample electronic device having an electronic component embedded in a ceramic material, similar to the view of  FIG. 2 . 
         FIG. 8  is a cross-sectional view of a fifth sample electronic device having an electronic component embedded in a ceramic material, similar to the view of  FIG. 2 . 
         FIG. 9  is a cross-sectional view of a sixth sample electronic device having an electronic component embedded in a ceramic material, similar to the view of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments discussed herein may take the form of a ceramic material having an electronic component embedded therein, and more particularly to a sapphire surface having an electrically energized component embedded within. In some embodiments, the sapphire surface may take the form of a portion of a housing for an electronic device. Since sapphire may be substantially transparent, it may form a cover glass for a display within or forming part of the electronic device, as one example. The cover glass may be bonded, affixed, or otherwise attached to a remainder of the housing, thereby forming an enclosure for the electronic device. 
     In some embodiments, the electronic component embedded in the ceramic material may be electrically active (e.g., powered). The electronic component may be active only at intervals or constantly, or at least constantly while the electronic device is on. As one example of an electrically active component, the electronic component may be an antenna. As another example of an electrically active component, the electronic component may be a sensor, such as a capacitive sensor. As a third example of an electrically active component, the electronic component may be a display, such as an organic light-emitting diode array. Yet a fourth example of an electronic component may be a ground or shield element, which is an example of a passive (e.g., not powered) component that may be embedded. 
     In embodiments where the electronic component is affected by, or vulnerable to, noise generated by other elements in the electronic device, moving the electronic component into the ceramic material may provide physical separation from these other elements and thus reduce or mitigate the effects of noise. It should be appreciated that the same is true in embodiments where the electronic component generates noise that adversely impacts the other elements in the electronic device. “Noise,” as used herein, generally includes any error or fluctuation induced in the operation of an electronic component or element, including parasitic capacitances, parasitic voltages, crosstalk, and the like. 
     In some embodiments, a shield or ground may be embedded within the ceramic near the electronic component in order to block noise between the component and other electronics within the electronic device. For example, a shield layer may be placed directly under the electronic device within the same space formed in the ceramic. 
     Typically, a void space may be formed within the ceramic in order to accept the electronic component and any optional shield or ground. A variety of sample methods for forming such a void space are discussed in more detail below. 
     Turning now to  FIG. 1 , a sample electronic device  100  incorporating a ceramic layer  105  and an electronic component  110  embedded in the ceramic layer is shown. The electronic device  100  may be, for example, a tablet device (as illustrated), a mobile phone, a portable computer, a wearable device, and so on. The ceramic layer  105  may abut a housing  115 . The ceramic layer  105  may be adjacent to, bonded to and/or directly abutting the housing  115 . The electronic device  100  is shown with the cover glass  105  proud of the housing  115 . In alternative embodiments, the cover glass may be flush with, or recessed within, the housing. Likewise, the cover glass is shown with a flat upper surface and an angled sidewall. In other embodiments, the upper surface may be curved or otherwise arcuate rather than planar, and the arc may continue along the cover glass such that no sharp angle with any sidewall is formed. 
     In the illustrated embodiment, the cover glass  105  overlaying the display may be made of a transparent ceramic such as sapphire. It should be appreciated that the cover glass  105  may be fully or at least partially formed from other materials such as alumina, chemically strengthened glass, and the like. For example, a layer of alumina may be used to bond two adjacent sapphire layers to one another. Likewise, an optically clear adhesive may be used to bond adjacent sapphire layers and may form part of the cover glass. Although the term “cover glass” may be used herein, it should be appreciated that this term imposes no requirement that glass be incorporated or used in the element. For example, a cover glass may be formed entirely from sapphire, or may be formed from sapphire and alumina, sapphire and adhesive, and so forth. Likewise, although the terms “cover glass” and “ceramic layer” may be used essentially interchangeably, certain embodiments of a “ceramic layer” may be replaced with (or encompass) non-ceramics, such as glass, plastic and so on. 
     A sample electronic component  110  is shown embedded within the cover glass  105 . The electronic element may be visible through the ceramic in certain embodiments and as shown. In alternative embodiments, the electronic element  110  may be placed beneath an ink layer or otherwise concealed so that it is not visible through the cover glass. As yet another option, the cover glass  105  may be opaque or translucent, at least in part, in order to conceal the electronic element. As still another option, the electronic element may be formed from a transparent or translucent material. 
     As previously mentioned, in one embodiment the electronic component  110  may include, incorporate, or be one or more antennas. For example, a first portion of the electronic component may be an antenna and a second portion may be a ground path. As yet another example, there may be multiple electronic components  110  taking the form of multiple, unconnected antennas, each of which may transmit and/or receive at a different frequency or band of frequencies. In still another embodiment, the multiple electronic antennas may be physically and/or operationally connected to one another. 
       FIG. 2  depicts a first sample cross-section taken along line A-A of  FIG. 1 . As shown in the cross-sectional view, a trench  200  may be formed in the sapphire or other ceramic material forming the cover glass  105 . The trench  200  may run about all four sides of the cover glass to form an annular groove, or may be discontinuous, such that multiple trench segments are formed as part of the overall trench. 
     The trench  200  may be formed through a variety of different operations. For example, the trench may be formed by computer numerical control (CNC) grinding, ultrasonic machining, laser ablation, plasma etching, laser etching (in addition to or without chemical etching), deep reactive ion etching, and so forth. In embodiments where laser ablation is used to form the trench  200 , the laser may be a femtosecond laser or any other suitable laser. 
     The electronic component  110  may be deposited in the trench  200 , filling at least a portion of the trench. The component may be pre-formed prior to deposit, or may be deposited in a liquid form and cool within the trench. Further, the electronic component  110  may extend the length of the trench  200  or may extend only partially along the trench. Likewise, as mentioned above, multiple electronic components may occupy a single trench and may be laid out without touching one another or may be laid out to at least partially overlap. 
     As one example, the electronic component  110  may be a conductive metal strip extending along at least a portion of the trench  200 . The metal may be heated until it is a liquid and poured into the trench; upon cooling, the liquid will generally occupy the deepest part of the trench. In many embodiments, the ceramic structure  105  may be inverted from its orientation shown in  FIG. 2  during addition of the electronic component  110 , such that the deepest part during addition of the electronic component is the “top” of the trench with respect to the orientation shown in  FIG. 2 . 
     In addition to depositing the electronic component  110  in a solid or liquid form, the electronic component may be deposited within the trench  200  through chemical vapor deposition or any other suitable deposition method. This may permit the bottom or walls of the trench  200  to be coated with the electronic component without requiring the center of the trench to be filled, for example and as shown in  FIG. 2 . 
     After the electronic component  110  is deposited, the remainder of the trench  200  not occupied by the component may be filled. In some embodiments, less than the total remainder of the trench is filled. The filler material  205  may be sapphire, alumina, glass (which may or may not be chemically strengthened), plastic, epoxy, poly(methyl methacrylate) (PMMA), polycarbonate, or the like, and may depend on the material forming the ceramic substrate. Typically, although not necessarily, in embodiments using an optically transparent ceramic  105 , the filler  205  has an index of refraction and transparency that is close or identical to that of the ceramic. By employing a filler that matches or comes close to the ceramic substrate with respect to these properties, optical aberrations in a finished enclosure may be reduced or eliminated. For example, alumina may be employed as a filler  205  in order to match the optical properties of sapphire. 
     As another option, a solid piece of ceramic may be used as a filler  205 . The ceramic filler may have a size and shape that approximately matches the dimensions of the trench  200 . This ceramic filler  205  may be bonded to the ceramic material forming the cover glass  105 , for example along the sides of the trench  200  or at any other region of the trench not filled by the electronic component  110 . In some embodiments, an optically clear adhesive may be used to bond the two. In other embodiments, a frit may be placed between the ceramic  105  and filler  205  and heated to bond the two. In still other embodiments, amorphous alumina or glass may be placed between the ceramic substrate and ceramic filler and heated to fuse the two together, for example at a molecular level. In some embodiments, an adhesive other than an optically clear adhesive may be employed. In yet other embodiments, an epoxy may bond the ceramic filler and the ceramic substrate. Fillers may be used with any or all embodiments discussed herein. 
     It should be appreciated that one or more through-holes (e.g., vias) may be formed when filling the trench  200 . These vias may be formed by leaving certain portions of the trench  200  unfilled, or by removing some of the filler  205 . The vias may permit electrical connection from the electronic component embedded within the trench to one or more electrical elements  210  within the housing. For example, a via may electrically connect the embedded electronic component to a power supply, a processor, a sensor, an electrical ground, and the like. These are all examples of electronic circuitry  210 . 
     Electronic circuitry  210  may likewise or further include a display stack that is viewable through the cover glass  105 . The display stack may generate graphics, text and/or other images that may be shown to a viewer of the electronic device  100 . For example, the display stack may be an LCD display stack, and LED display stack, an OLED display stack, and so on. The display stack may include a number of discrete elements or layers, including color filters, polarizers, lighting elements (such as back lights and/or edge lights), a pixel layer, TFT circuitry for driving pixels, and the like. In some embodiments, the display stack may also include touch-sensitive circuitry configured to recognize a touch on the cover glass  105  or elsewhere on the housing  115  of the device  100 . One example of such circuitry is a capacitive touch sensor array. In yet other embodiments, a biometric sensor (such as a capacitive fingerprint sensor) may be incorporated into the electronic circuitry, as may one or more force-sensitive sensors. 
     In some embodiments, multiple vias may extend through the filler in order to permit multiple electrical connections. This may be useful if there are multiple electronic components located within the trench, for example. It may also be useful if an electronic component requires more than one type of electrical connection (for example, some electronic components may require both power and an output connection). 
     After sealing the filler to the ceramic substrate, the resulting structure may be polished and finished. The exact method used to polish the ceramic and filler may vary with certain properties of the two, end uses of the cover glass (or other surface) formed by the combination of ceramic and filler, visibility of the back side of the ceramic and interface between ceramic and filler, and the like. For example, in embodiments where the ceramic is transparent and used as a cover glass or other visually transparent element, the interface between ceramic and filler may be smoother and/or more polished than in embodiments where the ceramic is translucent or opaque, and/or embodiments where the ceramic is not an external portion of the electronic device. 
     Accordingly, in certain embodiments the back surface of the ceramic (e.g., the surface of the ceramic on which the trench is formed) and/or the filler may be polished through annealing, mechanical polishing, chemical etching, aero lapping, and the like. In addition to polishing this surface of the ceramic and/or filler, certain of the foregoing techniques may likewise assist in bonding the filler to the ceramic. Annealing, as one example, may serve to at least partially bond the ceramic to the filler through its high heat of operation. 
     In some embodiments, an adhesive  215  may bond the cover glass  105  to the housing  115 . This adhesive may prevent ingress of particles from the environment to the interior of the electronic device  100 . In alternative embodiments, the adhesive  215  may be replaced with a barrier that may be affixed or adhered to either or both of the housing and cover glass. The barrier may be compressible in certain embodiments in order to provide a tight seal between the cover glass  105  and housing  115 . 
       FIG. 3A  is an exploded view of a ceramic substrate  105  (e.g., a cover glass), an electronic element  110  (such as an antenna), and a filler  205 . The trench  200  is shown on the underside of the ceramic substrate, which may be an optically transparent ceramic such as sapphire. 
     The trench  200  is generally sized to receive the electronic element  110 . Typically, the electronic component does not extend past any edge of the trench, but instead is fully contained within the trench. Although  FIG. 3A  depicts a single electronic component that is formed as a contiguous, unbroken rectangle, it should be appreciated that differently-shaped or configured electronic components may be employed. For example, multiple electronic components may be separated by one or more insulating spacers. Indeed, the size and shape of the electronic component  110  may vary somewhat from the size and shape of the trench  200 , even though the electronic component may fit fully within the trench. In some embodiments, as discussed above, the multiple electronic components may not be physically joined to one another or a single electronic component may be placed within the trench. 
     The filler  205  is also shown in  FIG. 3A . Although the filler is shown as a solid annular construct in  FIG. 3A , it should be appreciated that it may be granular, discontinuous, or otherwise formed from multiple pieces or parts. Typically, the filler  205  bonds to the ceramic substrate  105  and retains the electronic component  110  in place in the trench  200 . In some embodiments, the filler may also serve to electrically isolate or insulate the electronic component from other electronic elements within the device enclosure. Thus, the filler  205  may be chosen for its electrically insulating properties; for example, a material with a high dielectric constant may be chosen as a filler. One or more depressions or recesses  300  may be formed in the filler to accommodate one or more protrusions  112  of the antenna, as indicated in phantom in  FIG. 3A . 
       FIG. 3B  generally is a cross-sectional view taken along line  3 B- 3 B of  FIG. 3A , showing the cross-sectional structure of the trench  200  in the ceramic substrate  105 . It should be appreciated that the cross-sectional structure of the trench may vary between embodiments. For example, the trench may have a flat or angled bottom rather than a curved bottom. 
       FIG. 4  depicts a cross-sectional view of another embodiment  400 , again taken along line A-A of  FIG. 1 .  FIG. 4  generally depicts a cross-section of a cover glass  105  formed from multiple laminated layers of sapphire  405 ,  410 , or another suitable cover glass material. A receptacle, such as a trench  200 , may be formed in one of the sapphire layers and may hold the antenna or antennas. 
     In the embodiment shown in  FIG. 4 , the cover glass  105  may be formed from first  405  and second  410  cover glass layers that are bonded together. The first, outer layer  405  may have a depression  420  formed in its inner surface that is sized to accept the second, inner cover glass layer (see, for example,  FIG. 5B ). Thus, the outer layer  405  may be somewhat similar to a bucket—it may have a raised ledge or lip  425  running along its periphery, with the raised ledge extending inwardly into the outer layer. The raised ledge  425  may abut a base  430  of the depression  420 , thus forming a wall or walls around the depression. In some embodiments, the ledge may be formed by multiple sidewalls abutting one another. The sidewalls may meet at a sharp angle, such as a right angle, or may curved transitions may be formed between the sidewalls and connect the sidewalls. Likewise, the transition from the sidewall(s) to the base may be curved, sharp, angled, or the like. 
     The second, inner cover glass layer  410  may be sized to fit within, and substantially fill, the depression  420  in the outer cover glass layer  405 . Accordingly, the shape of the inner cover glass layer may be at least partially dictated by the shape of the depression  420  in the outer cover glass layer. In some embodiments, however, a spacer, filler or the like may be placed between the inner and outer cover glass layers. 
     Generally, a trough or groove  200  (e.g., a trench) may be formed in an upper surface of the inner cover glass layer  410 , as shown in  FIG. 4 . The antenna or other electronic component  110  may be formed in or placed in this groove prior to sealing the outer and inner cover glass layer. In such an embodiment, it may be relatively simple to place or form the antenna  110  within the embodiment  400 , since the upper surface of the inner cover glass layer  405  is exposed prior to bonding together the inner and outer cover glass layers. The antenna may be solid and placed within the trough  200 , may be deposited in vapor or particulate form into the trough, may be poured as a liquid into the trough (after which it may cool to form a solid), and so on. The antenna, when placed, may occupy the entirety of the trough in some embodiments, although in other embodiments the antenna may occupy only a portion of the trough. The occupied portion may be only a segment of the length of the trough, or may be a partial depth of the trough, or both. 
     It should be appreciated that the relative thicknesses of the outer and inner cover glass layers  405 ,  410  may vary from embodiment to embodiment. They need not be the same thickness at any point or along any cross-section. 
     Likewise, the exact location of the trough  200  may vary. It may be formed at any point along the inner cover glass layer  405  and may (or may not) extend fully around a perimeter of the cover glass layer  410 . The distance between an edge of the inner cover glass layer and the edge of the trough may vary as necessary or desired and need not be constant. Further, in some embodiments the trough  200  may be formed in the depression  420  of the outer cover glass layer  405  rather than in the inner cover glass layer  410 . 
     As discussed with respect to previous embodiments, the inner and outer cover glass layers  405 ,  410  may be bonded to one another with a chemical or mechanical bond, or any other suitable adhesive bond employing any suitable material including alumina, an adhesive (such as an optically clear adhesive), and the like. 
     As shown in  FIG. 4 , one or more vias  415  may connect the antenna or other electronic component  110  to the electronic circuitry  210  of the electronic device  400 . The vias  415  may be formed in the cover glass layer  410  in any of a number of fashions and may be filled with any suitable conductive material, including metal, ceramic, composites, and the like. 
     The size and/or shape of the vias  415  may vary not only from embodiment to embodiment, but also between vias of the same embodiment. Certain vias may be lozenge-shaped while others are round, for example. The via-filling material may be overmolded or overfill the via in some embodiments. Likewise, an end of the via  415  may be larger than a middle portion of the via to provide a larger contact surface to either the antenna or the electronic circuitry  210 . Thus, the cross-section of the via may vary along its length in some embodiments. 
     It should be appreciated that the vias  415  may be formed by a similar or identical process as used to form the antenna  110 , for example physical vapor deposition. The vias may be formed in a separate deposition process, for example after the antenna is formed and after the inner and outer cover glass layers  405 ,  410  are bonded to one another. As another example, the vias  415  may be flooded with a liquid metal, which may then dry to fill the vias and form electrical connections to the antenna(s). 
       FIG. 5A  generally shows an exploded view of the outer cover glass layer  405 , the antenna  110 , and the inner cover glass layer  410 . Although not shown in  FIG. 4 , one or more holes may be formed in the outer cover glass layer to accept one or more protrusions of the antenna. In embodiments where the protrusions (if any) project downward, such holes may be formed in the inner cover glass layer  410  and may be formed as deeper sections of the trough  200 . 
     The cross-sectional shape of the outer cover glass layer  405  is shown to best effect in  FIG. 5B , which is a cross-sectional view taken along line  6 B- 6 B of  FIG. 5A .  FIG. 5B  illustrates the “bucket” shape of the depression  420  as formed by the sidewalls  425  and base  430 . 
       FIG. 6  shows another embodiment  600  of an electronic device having an electronic component  110  embedded in a cover glass  105 . As previously discussed, the cover glass may be formed from a ceramic, one example of which is sapphire. 
       FIG. 6  is generally similar to  FIG. 4  except that the trough  200  containing the antenna  110  is formed in the outer cover glass layer  605 . Although no via is shown in  FIG. 6 , vias may extend through the inner cover glass layer  610  from the electronic circuitry  210  to the antenna  110 . Placing the via closer to an exterior surface of the cover glass  105  and further from the electronic circuitry  210  may improve operation of the antenna and may prevent or reduce cross-talk and/or other interference between the antenna and the electronic circuitry. 
       FIG. 7  depicts a cross-sectional view similar to those of  FIGS. 4 and 6 , showing yet another embodiment  700  having an antenna  110  embedded in a ceramic material. In this embodiment, the antenna may be formed or placed within a slot or groove  705  that runs about an exterior edge  710  of the cover glass  105 . Thus, at least a portion of the antenna  110  may be flush with an edge  710  of the cover glass  105 . In some embodiments, the antenna edge may be exposed to the environment while in other a coating may be applied over the antenna&#39;s edge and, optionally, at least part of the edge of the cover glass and/or housing to provide shielding from environmental effects and hazards. 
     In the embodiment of  FIG. 7 , the groove/slot  705  may be formed at any time, such as before or after the inner and outer ceramic layers  715 ,  720  are affixed to one another. Some embodiments may use a single sheet of ceramic rather than the inner and outer layers depicted in  FIG. 7 . 
       FIG. 8  is another cross-sectional view of an embodiment  800  similar to that of  FIG. 7 . Here, however, the cover glass  105  is split into upper and lower cover glass layers  805 ,  810 . The layers are not nested together as is the case in the embodiments shown in  FIGS. 4 and 6 . Rather, the layers form the upper and lower portions of the cover glass and sit adjacent to one another with an interface  815  defining the point of contact. The interface  815  may be planar, such that the opposing sides of the upper and lower cover glass layers are flat. As with other embodiments, the layers may be bonded to one another, for example with an optically clear adhesive. 
     The slot  820  for the antenna  110  may be formed in either of the upper and lower cover glass layers  805 ,  810  or may be partially in both layers, although the slot is shown in  FIG. 7  in the upper cover glass layer. Likewise, the slot  820  need not necessarily be formed in either layer adjacent the interface  815  between the layers. It may be more convenient and/or simpler to create the slot at the interface, however, since the slot may then be formed in an exposed surface of at least one of the cover glass layers prior to bonding the two together. Again, one or more vias may extend through the lower cover glass layer  810  and connect the antenna to the electronic circuitry. 
       FIG. 9  is another cross-sectional view of an embodiment  900  similar to that of  FIGS. 7 and 8 . Here, similar to  FIG. 8 , the cover glass  105  is split into upper and lower cover glass layers  905  and  910 . As with  FIG. 8 , the layers for the upper and lower portions of the cover glass  905  and  910 , sitting adjacent to one another at an interface  915 , which may be planar so that the layers lay flat. As with other embodiments, the layers may be bonded to one another, for example with an optically clear adhesive. 
     The slot, groove or other aperture  920  (“slot”) for the antenna  110  may be formed in either of the upper and lower cover glass layers  905 ,  910  or may be partially in both layers, although the slot is shown in  FIG. 9  in the upper cover glass layer  105 . Likewise, the slot  920  need not necessarily be formed in either layer adjacent the interface  915  between the layers. It may be more convenient and/or simpler to create the slot at the interface, however, since the slot may then be formed in an exposed surface of at least one of the cover glass layers prior to bonding the two together. Again, one or more vias may extend through the lower cover glass layer  910  and connect the antenna to the electronic circuitry. The one or more vias may extend through a portion of the upper cover glass layer  905  for embodiments in which the slot  920  is not formed entirely within the upper cover glass layer  905 . 
     As noted above, the electronic circuitry may include a display stack  250  that is viewable through the cover glass  905 . The display stack may generate graphics, text and/or other images via an LCD display stack, and LED display stack, an OLED display stack, or any other suitable display stack. The display stack may include a number of discrete elements or layers, including color filters, polarizers, lighting elements (such as back lights and/or edge lights), a pixel layer, TFT circuitry for driving pixels, and the like. In some embodiments, the display stack may also be positioned below touch-sensitive circuitry  240  configured to recognize a touch on the cover glass  105  or elsewhere on the housing of the device  900 . One example of such circuitry is a capacitive touch sensor array. The touch-sensitive circuitry may take the form of a layer either located above the display (with respect to the orientation shown in  FIG. 9 ) or in-plane with the pixels of the display. 
     In yet other embodiments, a biometric sensor (such as a capacitive fingerprint sensor) may be incorporated into the electronic circuitry, as may one or more force-sensitive sensors. 
     In other embodiments, the electronic circuitry may include other elements. For example, the electronic circuitry may include a wireless communication element  260  separate from the antenna  110 . A wireless communication element  260  may be a Bluetooth element, a Wi-Fi element, a near-field communication element, or other radio frequency elements. Such a communication element may be placed below the display, as shown in  FIG. 9 . 
     In still further embodiments, the electronic device may also include a sensor  230  positioned below the electronic circuitry. The sensor  930  may be any number of different sensor types. For example, in certain embodiments, the sensor  930  may be a motion or orientation sensor such as a gyroscopic sensor or accelerometer. In other embodiments, the sensor  930  may be an optical sensor such as an ambient light sensor. An optical sensor may be positioned and oriented to receive and measure external light through the upper and lower cover glass layers  905  and  910  and the electronic circuitry  210 , including touch-sensitive circuitry  240 , display stack  250 , and/or wireless communication element  260 , as shown in  FIG. 9 . An optical sensor may be an ambient light sensor, a color sensor, a proximity sensor, or other suitable optical sensor. In such a case, the electronic circuitry  210  may be at least partially optically clear. In other embodiments, electronic circuitry  210  may include an aperture positioned above the sensor  930 . As still another option, the optical sensor may receive ambient light transmitted through the cover glass and between pixels of the display 
     In some embodiments, one or more ink layers may be deposited beneath at least a portion of the cover glass to provide decoration and/or to mask the presence of the antenna. The region of the cover glass beneath the antenna may be colored to obscure the antenna, for example. Such ink layers are purely optional. In embodiments having one or more ink coatings, the ink may be selectively deposited so as to not cover the vias, thereby permitting electrical connections between the antenna(s) and the electronic circuitry through the vias. 
     Some embodiments may have a trench or passage formed entirely within a cover glass. For example, a laser may be used to selectively excite ceramic molecules at a certain depth beneath the surface of the cover glass. These excited molecules may vaporize while the molecules surrounding them may remain relatively stable and unaffected. Thus, a void may be formed in the interior of the cover glass without requiring any through-holes to be formed or any chemicals to be used. Vias may later be formed to connect to the void; these vias may permit the antenna material to be deposited within the void as necessary. The vias may then be filled or sealed with an appropriate material. Similarly, the laser may be selectively applied to the sapphire lattice at a depth within cover glass to weaken the bonds between molecules. These molecules with weakened bonds may then be more easily etched with a chemical etchant to form a passage or path through the sapphire, into which an antenna or other electronic component may be deposited. Vias may be formed in the same fashion and, optionally, in conjunction with forming the internal trench. 
     In yet other embodiments, a shield may be placed between the electronic component and the electronic circuitry. For example, just as one or more ink layers may be deposited on the underside of the cover glass or otherwise between the cover glass and electronic circuitry, a shield may likewise be placed therebetween. The shield may insulate the electronic component in the cover glass from noise, parasitic capacitances and other undesirable electrical effects caused by proximity to the electronic circuitry and vice versa. In some embodiments, the shield may be a ground plane. Further, in embodiments employing a shield, the ink (if used) may be deposited on the shield itself and the shield may additionally provide structural support to the cover glass. 
     Although various embodiments have been described herein, it should be appreciated that variants and changes will be apparent to those of skill in the art upon reading the disclosure. Accordingly, the proper scope of protection is set forth in the following claims.

Metadata:
Filing Date: 20141013
Publication Date: 20170613
Grant Date: 20170613
Priority Date: 20130923
Inventors: MEMERING DALE N.
DE JONG ERIK G.
ROTHKOPF FLETCHER R.
WEISS SAMUEL BRUCE
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F1/1656", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F2200/1633", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01Q1/1271", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2200/1634", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/2258", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/2258", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/1271", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1656", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F2200/1633", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2200/1634", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 52690741