PATENT DOCUMENT

Publication Number: US-9863927-B2
Application Number: US-201414175845-A
Country: US
Kind Code: B2

Title: Method of inspecting sapphire structures and method of forming the same

Abstract:
A method of inspecting and forming sapphire structures. The method of inspecting a sapphire structure may include providing an annealed sapphire structure, and measuring a profile of at least a portion of the annealed sapphire structure. The profile of at least the portion of the annealed sapphire structure may be measured using a non-x-ray based measuring device. Additionally, the method of inspecting may include identifying a defect within at least a portion of the measured profile of the annealed sapphire structure.

Claims:
We claim: 
     
       1. A method of inspecting a sapphire structure, comprising:
 providing an annealed sapphire structure having a group of distinct terraced protrusions; 
 measuring a profile of at least a portion of the annealed sapphire structure, the measuring comprising:
 detecting a set of height values of the group of distinct terraced protrusions; and 
 detecting a set of distance values between peaks of the group of distinct terraced protrusions; 
 
 determining an estimated crystallographic plane orientation for the annealed sapphire structure based on the set of height values and the set of distance values; and 
 identifying a defect within at least a portion of the measured profile of the annealed sapphire structure using the estimated crystallographic plane orientation. 
 
     
     
       2. The method of  claim 1 , wherein the identifying of the defect further comprises at least one of:
 comparing the set of height values with a predetermined acceptable height; and 
 comparing the set of distance values with a predetermined acceptable peak distance. 
 
     
     
       3. The method of  claim 2 , wherein the identifying of the defect within at least the portion of the measured profile of the annealed sapphire structure further comprises at least one of:
 determining the set of height values differs from the predetermined acceptable height; and 
 determining the set of distance values differs from the predetermined acceptable peak distance. 
 
     
     
       4. The method of  claim 2 , wherein:
 the predetermined acceptable height includes a height of acceptable terraced protrusions for the annealed sapphire structure; and 
 the acceptable terraced protrusions of the annealed sapphire structure are substantially free from the defect. 
 
     
     
       5. The method of  claim 4 , wherein:
 the predetermined acceptable peak distance includes a peak distance of the acceptable terraced protrusions for the annealed sapphire structure; and 
 the acceptable terraced protrusions of the annealed sapphire structure are substantially free from the defect. 
 
     
     
       6. The method of  claim 1 , wherein the measuring of the profile further comprises:
 detecting the set of height and distance values using one of:
 a differential interference contrast (DIC) microscope; 
 an interferometer; or 
 a profilometer. 
 
 
     
     
       7. The method of  claim 1 , wherein the defect includes an optical defect formed in the top surface of the annealed sapphire structure. 
     
     
       8. A method of inspecting a sapphire substrate, comprising:
 providing an annealed sapphire substrate; 
 inspecting a profile of a surface of the annealed sapphire substrate by detecting at least one of:
 a defect region defined by a first group of terraced protrusions indicating that a crystallographic plane orientation satisfies a first alignment condition with respect to the surface of the sapphire substrate; or 
 a defect-free region defined by a second group of terraced protrusions indicating that the crystallographic plane orientation satisfies a second alignment condition with respect to the surface of the sapphire substrate; and 
 
 in response to a detection of defect region, performing at least one surface treatment to the sapphire substrate. 
 
     
     
       9. The method of  claim 8 , wherein the performing the at least one surface treatment comprises:
 depositing at least one decorative layer over a portion of the sapphire substrate. 
 
     
     
       10. The method of  claim 8 , wherein the performing of the at least one surface treatment comprises:
 lapping a portion of the sapphire substrate; and 
 polishing the lapped portion of the sapphire substrate. 
 
     
     
       11. The method of  claim 8 , wherein the performing of the at least one surface treatment comprises:
 re-annealing the sapphire substrate. 
 
     
     
       12. The method of  claim 8 , wherein the inspecting further comprises at least one of:
 comparing a set of height values of the first or second groups of distinct terraced protrusions with a predetermined acceptable height; and 
 comparing a set of distance values of the first or second groups of distinct terraced protrusions with a predetermined acceptable peak distance. 
 
     
     
       13. The method or  claim 12 , wherein the inspecting further comprises at least one of:
 determining the set of height values of the first or second groups of distinct terraced protrusions differs from the predetermined acceptable height; and 
 determining the set of distance values of the first or second groups of distinct terraced protrusions differs from the predetermined acceptable peak distance. 
 
     
     
       14. The method of  claim 8 , wherein the inspecting of the profile further comprises:
 detecting at least one of the defect region or the defect-free region using at least one of:
 a differential interference contrast (DIC) microscope; 
 an interferometer; or 
 a profilometer.

Description:
TECHNICAL FIELD 
     The disclosure relates generally to product inspection and manufacturing methods, and more particularly, to methods for inspecting and forming sapphire structures. 
     BACKGROUND 
     Current electronic devices continue to become more prevalent in day-to-day activities. For example, smart phones and tablet computers continue to grow in popularity, and provide everyday personal and business functions to its users. These electronic devices typically include large screens or displays utilized by the user to interact (e.g., input/output) with the electronic devices. 
     Conventionally these screens or displays are made from reinforced or modified glass. However, these glass screens may still be susceptible to damage. Specifically, these conventional screens may scratch, chip or crack when an undesirable impact event or force (e.g., drop, crushed) occurs with the electronic device. Damage to the screens of the electronic device may render the device partially, or completely, inoperable and/or may prevent the user from utilizing the electronic device for its intended purposes. 
     The use of the crystalline form of alumina (Al 2 O 3 ) (e.g., Corundum), commonly known as sapphire, is becoming more of a viable option for replacing the glass screen or display. Specifically, with improved manufacturing processes of single crystal sapphire, and the improved elemental characteristics (e.g., hardness, strength) of sapphire over glass, sapphire may be an acceptable replacement material for conventional glass screens and displays. However, the same chemical/elemental characteristics that make sapphire a superior material choice over glass, also make the manufacturing of sapphire difficult. For example, sapphire utilized to make screens for electronic device typically undergo a final annealing process before further cosmetic process are performed. During this annealing process, the top surface of the sapphire may “heal,” or fill in micro-cracks formed during other processes (e.g., lapping, cutting, planing). More specifically, surface atoms of the sapphire may be substantially mobile during the annealing process and may rearrange themselves to fill in the micro-cracks formed on the top surface. 
     However, in addition to filling these micro-cracks, the surface atoms may rearrange themselves during the annealing process to form a plurality of terraced protrusions in the top surface. These terraced protrusions may vary dependent upon a plurality of factors including, but not limited to, the crystallographic orientation of the sapphire and the operational characteristics (e.g., time, temperature, atmosphere) of the annealing process. While some terraced protrusions formed on the top surface of the sapphire may not negatively affect the quality of the sapphire, other protrusions may cause cosmetic defects in the sapphire. For example, some terraced protrusions may create colorful light reflections on the surface the sapphire. These reflections may negatively impact the sapphire when used as a screen or display for an electronic device by obstructing a user&#39;s ability to see the content featured on the screen of the electronic device clearly. That is, when a colorful light reflection occurs on the sapphire structure, that reflection may block or prevent a user from seeing at least a portion of the content being displayed on the screen. As a result, the functionality of the electronic device is diminished because of the cosmetic defect caused by the terraced protrusions formed on the sapphire&#39;s top surface. 
     SUMMARY 
     Generally, embodiments discussed herein are related to methods of inspecting sapphire structures and methods of forming the sapphire structure. The method of inspecting the sapphire structures may include measuring a profile of the sapphire structure, and determining if the top surface of the sapphire structure includes a defect. The defect of the top surface may be identified where the profile of the top surface includes a configuration that may not conform with an acceptable configuration. The measuring and subsequent identifying of this defect may be achieved using a non-x-ray based measuring device. As a result of being able to identify a defect in the top surface of the sapphire structure using a non-x-ray based measuring device, sapphire structures may be inspected more easily, more quickly and more cost-effectively, than conventional ways which include x-ray measuring devices. Additionally, each individual sapphire structure may be inspected using the method discussed herein. By inspecting the sapphire structures using the methods described herein, manufacturers may be able to improve quality control of the sapphire structure, and/or may examine every sapphire structure before it is implemented in its final function (e.g., screen for electronic device). 
     One embodiment may include a method of inspecting a sapphire structure. The method of inspecting may include providing an annealed sapphire structure, and measuring a profile of at least a portion of the annealed sapphire structure. The profile of at least the portion of the annealed sapphire structure may be measured using a non-x-ray based measuring device. Additionally, the method of inspecting may include identifying a defect within at least a portion of the measured profile of the annealed sapphire structure. 
     A further embodiment may include a method of forming a sapphire structure. The method may include treating at least a top surface of the sapphire structure, annealing the treated sapphire structure, and inspecting at least a portion of the top surface of the annealed sapphire structure. The portion of the top surface of the annealed sapphire structure may be inspected using a non-x-ray based measuring device. The method of forming the sapphire structure may also include identifying a defect within the inspected portion of the top surface of the annealed sapphire structure. Additionally, in response to identifying a defect within the inspected portion of the top surface of the annealed sapphire structure, the method may include at least one of: re-treating the inspected portion of the annealed sapphire structure, and re-annealing the inspected portion of the annealed sapphire structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIG. 1  shows an illustrative plane view of an electronic device including a sapphire structure, according to embodiments. 
         FIG. 2  shows an illustrative perspective view of a sapphire structure, according to embodiments. 
         FIG. 3  is a flow chart illustrating a method for inspecting a sapphire structure. This method may be performed on a sapphire structure as shown in  FIGS. 1 and 2 . 
         FIG. 4A  shows an illustrative plane view of an annealed sapphire structure undergoing processes of inspecting as depicted in  FIG. 3 , according to embodiments. 
         FIGS. 4B-4G  show illustrative front cross-sectional views of a portion of the annealed sapphire structure of  FIG. 4A  undergoing processes of inspection as depicted in  FIG. 3 , according to embodiments. 
         FIG. 5  is a flow chart illustrating a method of forming a sapphire structure, according to embodiments. 
         FIGS. 6A-6H  show illustrative front cross-sectional views of a portion of a sapphire structure undergoing processes of formation as depicted in  FIG. 5 , according to embodiments. 
     
    
    
     It is noted that the drawings of the invention are not necessarily to scale. The drawings are intended to depict only typical aspects of the invention, and therefore should not be considered as limiting the scope of the invention. In the drawings, like numbering represents like elements between the drawings. 
     DETAILED DESCRIPTION 
     Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following descriptions are not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims 
     The following disclosure relates generally to product inspection and manufacturing methods, and more particularly, to methods for inspecting and forming sapphire structures. 
     In a particular embodiment, a method of inspecting a sapphire structures may include measuring a profile of the sapphire structure, and determining if the top surface of the sapphire structure includes a defect. The defect of the top surface may be identified where the profile of the top surface includes a configuration that may not conform with an acceptable configuration. The measuring and subsequent identifying of this defect may be achieved using a non-x-ray based measuring device. As a result of being able to identify a defect in the top surface of the sapphire structure using a non-x-ray based measuring device, sapphire structures may be inspected more easily, more quickly and more cost-effectively, than conventional ways which include x-ray measuring devices. Additionally, each individual sapphire structure may be inspected using the method discussed herein. By inspecting the sapphire structures using the methods described herein, manufacturers may be able to improve quality control of the sapphire structure, and/or may examine every sapphire structure before it is implemented in its final function (e.g., screen for electronic device). 
     The method of inspecting a sapphire structure may include providing an annealed sapphire structure, and measuring a profile of at least a portion of the annealed sapphire structure. The profile of at least the portion of the annealed sapphire structure may be measured using a non-x-ray based measuring device. Additionally, the method of inspecting may include identifying a defect within at least a portion of the measured profile of the annealed sapphire structure. 
     The method of forming may include treating at least a top surface of the sapphire structure, annealing the treated sapphire structure, and inspecting at least a portion of the top surface of the annealed sapphire structure. The portion of the top surface of the annealed sapphire structure may be inspected using a non-x-ray based measuring device. The method of forming the sapphire structure may also include identifying a defect within the inspected portion of the top surface of the annealed sapphire structure. Additionally, in response to identifying a defect within the inspected portion of the top surface of the annealed sapphire structure, the method may include at least one of: re-treating the inspected portion of the annealed sapphire structure, and re-annealing the inspected portion of the annealed sapphire structure. 
     These and other embodiments are discussed below with reference to  FIGS. 1-6H . However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these Figures is for explanatory purposes only and should not be construed as limiting. 
     Referring now to  FIG. 1 , there is shown a plane perspective view of one example of an electronic device  10  that can include, or be connected to a biometric sensing device (not shown). In the illustrated embodiment, electronic device  10  is implemented as a smart telephone. Other embodiments can implement the electronic device  10  differently, such as, for example, as a laptop or desktop computer, a tablet computing device, a gaming device, a display, a digital music player, a wearable computing device or display such as a watch or glasses, and other types of electronic devices that can receive biometric data from a biometric sensing device. 
     The electronic device  10  includes a casing  12  at least partially surrounding a display  14  and one or more button assemblies  16 . Enclosure  12  can form an outer surface or partial outer surface and protective case for the internal components of electronic device  10 , and may at least partially surround display  14 . Enclosure  12  can be formed of one or more components operably connected together, such as a front piece and a back piece. Alternatively, enclosure  12  can be formed of a single piece operably connected to the display  14 . Button assembly  16  may be utilized by electronic device  10  to provide user input and/or allow the user to interact with the various functions of electronic device  10 . 
     Additionally, where electronic device  10  is implemented as a smart telephone, electronic device  10  may also include a speaker component  18  positioned within enclosure  12 . As shown in  FIG. 1 , display  14  may include an opening  20  formed through the display  14 , where opening  20  may be in alignment with speaker component  18  of electronic device  10 . Opening  20  may be formed through display  14  to substantially prevent obstruction of the sound emitted by speaker component  18  during operation of electronic device  10 . 
     Display  14  can be implemented with any suitable technology, including, but not limited to, a multi-touch sensing touchscreen that uses liquid crystal display (LCD) technology, light emitting diode (LED) technology, organic light-emitting display (OLED) technology, organic electroluminescence (OEL) technology, or another type of display technology. Electronic device  10  may include a sapphire structure  100  covering display  14 . More specifically, sapphire structure  100  may be included in electronic device  10  as a protective layer or window included in display  14 . Sapphire structure  100  may be the external component or surface of display  14 , and may allow a user to interact with the electronic device  10 , without contacting and/or harming the internal components (e.g., liquid crystal, circuitry, and the like) of display  14  and device  10 . 
     Turning to  FIG. 2 , a perspective view of a sapphire structure  100  is shown according to embodiments of the invention. Sapphire structure  100 , as shown in  FIG. 2 , may be a pre-cut piece of artificially grown corundum to be used in electronic device  10  of  FIG. 1 . The artificially grown corundum used to form sapphire structure  100  may be grown using any conventional growth process including, but not limited to: hydrothermal growth; vertical horizontal gradient freezing (“VHGF”); edge-defined film-fed growth (“EFG”); horizontal moving growth (e.g., Bridgman growth); and Kyropoulos growth. 
     Sapphire structure  100  may include a top surface  102  and a bottom surface  104  positioned opposite top surface  102 . When included or implemented in electronic device  10  ( FIG. 1 ), top surface  102  may be exposed to a user for interacting with electronic device  10 , and bottom surface  104  may be positioned substantially within enclosure  12  of electronic device  10 . Sapphire structure  100  may be retained within enclosure  12  of electronic device  10  using any conventional coupling technique including, but not limited to: snap-fit, compression fit, adhesive, weld, and bonding. For example, sapphire structure  100  may be coupled to enclosure  12  by including an adhesive on bottom surface  104  and/or sidewalls  106 ,  108 . That is, sapphire structure  100  may be inserted into enclosure  12 , and the adhesive on bottom surface  104  and/or sidewalls  106 ,  108  may contact a portion of enclosure  12 , to couple sapphire component  100  within enclosure  12  to protect and/or provide a window to display  14 . As shown in  FIG. 2 , sidewalls  106 ,  108  may be substantially perpendicular to top surface  102  and bottom surface  104 , respectively. However, it is understood that sidewalls  106 ,  108  may be substantially angled relative to top surface  102  for fitting and retaining sapphire structure  100  within enclosure  12  of electronic device  10 . For example, where sidewalls  106 ,  108  include substantially angled surfaces, a portion of enclosure  12  adjacent display  14  may include a conversely angled surface to abut and/or contact the angled sidewall  106 ,  108  to fix sapphire structure  100  within enclosure  12 . Additional configurations for sidewalls  106 ,  108  of sapphire structure  100  for retaining sapphire structure  100  within enclosure may also be understood. For example, sidewalls  106 ,  108  may include a protrusion portion (not shown) for contacting a portion of enclosure  12  to substantially fix sapphire structure  100  within enclosure  12 . 
     As shown in  FIG. 2 , sapphire structure  100  may also include a plurality of plane orientations for the surfaces (e.g., top surface  102 , sidewalls  106 ,  108 ) of sapphire structure  100 . More specifically, each of the surfaces of sapphire structure  100  may be in alignment with a crystallographic plane orientation determined by the formation of sapphire structure  100 . For example, as shown in  FIG. 2 , top surface  102  may include an offset A-plane crystallographic orientation, while sidewall  106  may include a C-plane crystallographic orientation. Top surface  102  may be offset from the A-plane crystallographic orientation by a determinable degree (θ). The offset determinable degree (θ) may be a result of an error in the initial processes of forming sapphire structure  100 . For example, and as discussed herein, sapphire structure  100  may not be cut from a large piece of grown corundum at a desired crystallographic plane (C-plane), but rather may be cut at an offset degree (θ) from the desired plane. 
     It is understood that corundum (e.g., sapphire) is an anisotropic material. As a result, the crystallographic orientation of the surfaces of components made from corundum or sapphire (e.g., sapphire structure  100 ) may affect the physical properties and/or material characteristics (e.g., strength, ductility, elasticity) of the component. It is also understood that the crystallographic orientation of the various surfaces (e.g., top surface  102 , sidewalls  106 ,  108 ) may be dependent on the growing processes used for creating the corundum of sapphire structure  100  and/or the cutting process for forming sapphire structure  100  from the corundum. For example, the corundum from which sapphire structure  100  is formed may be grown using an EFG growth process. In the growth process, the seed crystal may include a plane orientation to yield corundum that may allow for specific, desired planes (e.g., C-plane, A-plane) to be utilized in components formed from the corundum (e.g., sapphire structure  100 ). By knowing the orientation of the seed crystal used in the EFG growth process, and ultimately knowing the crystallographic orientation of the grown corundum, manufactures can cut the corundum in a specific direction to form components with surfaces having specific plane crystallographic orientations, or substantially desirable plane crystallographic orientations. 
     Turning to  FIG. 3 , a method for inspecting a sapphire structure (see,  FIGS. 4A-4G ) is now discussed. Specifically,  FIG. 3  is a flowchart depicting one sample method  300  for inspecting an annealed sapphire structure. 
     In operation  302 , the annealed sapphire structure may be provided. The annealing process performed on the annealed sapphire structure, as discussed herein, may include the application of heat at an annealing temperature to the sapphire structure, over a predetermined annealing time, at a predetermined atmospheric pressure. Additionally, and as discussed herein, the annealing process performed on the sapphire structure may be performed to substantially “heal” and/or correct imperfections (e.g., cracks, gaps) on a top surface of the sapphire structure. The imperfections may be formed in the top surface while performing the initial processes (e.g., grinding, lapping, planning, cutting, polishing) for creating the annealed sapphire structure. 
     The annealing of the sapphire structure may also create additional features on the top surface of the sapphire structure. More specifically, the performing of an annealing process on the sapphire structure may result in the formation of a plurality of terrace protrusions formed on the top surface of the sapphire structure. The plurality of terraced protrusions are formed as a result of the corundum, used to form the annealed sapphire structure, typically including surface atoms having substantial mobility during an annealing process. That is, during the annealing process, these surface atoms of the sapphire structure may be able to move about the top surface of the sapphire structure. Due to the surface atom&#39;s mobility, the annealing process may be performed on the sapphire structure to allow the surface atoms to move and subsequently heal/fill-in any cracks or gaps that may be formed in the top surface during previous processing of the sapphire structure. However, because of the mobility of the surface atoms, and the anisotropic properties of the annealed sapphire structure, the atoms may also substantially move and/or arrange themselves in configuration that requires the least amount of energy. Typically, this causes the surface atoms to rearrange themselves to be in substantial alignment with a crystallographic plane of the annealed sapphire structure. As briefly discussed above, and discussed in detail below, where a plane of the annealed sapphire structure is offset by an angle (e.g.,  FIG. 2 , θ), the surface atoms will rearrange themselves into a terraced protrusion formation on the top surface of the sapphire structure. 
     In operation  304 , a profile of a portion of the annealed sapphire structure may be measured using a non-x-ray based measuring device (see,  FIG. 4C , non-x-ray device  428 ). The measuring of the profile may include determining the geometry of the plurality of terraced protrusions included in the annealed sapphire structure. More specifically, the measuring of the profile may include determining an actual height and actual peak-to-peak or peak distance of each of the plurality of terraced protrusions formed in the top surface of the annealed sapphire structure. 
     The non-x-ray based measuring device, utilized in operation  304 , may include a variety of conventional measuring devices configured to measure a profile of a portion of the annealed sapphire structure. More specifically, the non-x-ray based measuring device may include a differential interference contrast (DIC) microscope, an interferometer, a profilometer, or any other conventional non-x-ray based measuring device that may be capable of depicting a profile of the sapphire structure. The non-x-ray based measuring device may be utilized by a user (e.g., quality control inspector, manufacturer, etc.) or by an automated system configured to perform the inspection process as discussed herein with respect to  FIG. 3 . 
     In operation  306 , a defect may be identified within the portion of the measured profile of the annealed sapphire structure. The identifying of the defect of the annealed sapphire structure may include comparing the actual height and peak distance of the plurality of terraced protrusions, determined in operation  304 , with respective predetermined acceptable heights and predetermined acceptable peak distances. As discussed herein, the predetermined acceptable height and the predetermined acceptable peak distance may include a maximum height and peak distance, respectively, for the sapphire structure that may be substantially free from the defect. Where the actual height and/or peak distance exceed the predetermined acceptable height and/or peak distance, a defect may be identified, as discussed herein. The defect of the annealed sapphire structure may include a substantially undesirable, optical defect formed in the top surface. More specifically, where the defect includes an optical defect caused by terraced protrusions formed on the top surface during the annealing process, the annealed sapphire structure may include undesirable, colorful light reflections on the top surface when the sapphire structure is exposed to light. When the sapphire structure including the optical defect is implemented within electronic device  10  (see,  FIG. 1 ), the optical defects may substantially obstruct a user&#39;s ability to see display  14 , which may undesirably reduce the intended functionality of electronic device  10 . 
     Turning to  FIGS. 4A-4G , a plane and side cross-sectional views of various portions of an annealed sapphire structure  400  undergoing method  300 , as depicted in  FIG. 3 , are shown. It is understood that similarly numbered components may function in a substantially similar fashion. Redundant explanation of these components has been omitted for clarity. 
     As shown in  FIG. 4A , annealed sapphire structure  400  may be provided. The providing of annealed sapphire structure  400  in  FIG. 4A  may correspond to operation  302  in  FIG. 3 . Annealed sapphire structure  400  may be substantially similar to sapphire structure  100  discussed herein with respect to  FIG. 2 . However, annealed sapphire structure  400 , as shown in  FIG. 4A , may have undergone an annealing process. The annealing process performed on annealed sapphire structure  400 , as discussed herein, may include the application of heat at an annealing temperature to annealed sapphire structure  400 , over a predetermined annealing time, at a predetermined atmospheric pressure. Additionally, and as discussed herein, the annealing process performed on annealed sapphire structure  400  may be performed to substantially “heal” and/or correct imperfections (e.g., cracks, gaps) on top surface  402 . 
     As shown in  FIG. 4A , top surface  402  may include a plurality of distinct terraced protrusion portions  410 ,  412 ,  414 ,  416 . More specifically, top surface  402  of annealed sapphire structure  400  may include a plurality of distinct portions including terraced protrusions  410 ,  412 ,  414 ,  416  formed during the annealing process. As discussed herein, the plurality of terraced protrusions  410 ,  412 ,  414 ,  416 , are formed on top surface  402  as a result of the corundum used to form annealed sapphire structure  400  typically including surface atoms having substantial mobility during an annealing process of annealed sapphire structure  400 . That is, during the annealing process, these surface atoms of annealed sapphire structure  400  may be able to move about top surface  402  of sapphire structure. Due to the surface atom&#39;s mobility, the annealing process may be performed on annealed sapphire structure  400  to allow the surface atoms to move and subsequently heal/fill-in any cracks or gaps that may be formed in top surface  402  during previous processing of annealed sapphire structure  400 . However, because of the mobility of the surface atoms, and the anisotropic properties of annealed sapphire structure  400 , the atoms may also substantially move and/or arrange themselves in configuration that requires the least amount of energy. Typically, this causes the surface atoms to rearrange themselves to be in substantial alignment with a crystallographic plane of annealed sapphire structure  400 . As briefly discussed above, and discussed in detail below, where a plane of annealed sapphire structure  400  is offset by an angle (e.g.,  FIG. 2 , θ), the surface atoms will rearrange themselves into a terraced protrusion formation  410 ,  412 ,  414 ,  416 . 
     Each of the plurality of distinct terraced protrusion  410 ,  412 ,  414 ,  416  may be distinct from each other, and from other portions of top surface  402  of annealed sapphire structure  400 . More specifically, as shown in  FIG. 4A , and discussed herein, each of the distinct plurality of terraced protrusion portions  410 ,  412 ,  414 ,  416  of top surface  402  may be configured with distinct dimensions from each other and from the remaining portion  418  (e.g., unpatterned) of top surface  402 . The remaining portion  418  (e.g., unpatterned) of top surface  402  may also include terraced protrusions as a result of the rearrangement of the surface atoms of annealed sapphire structure  400  during the annealing process. However, the terraced protrusions positioned in remaining portion  418  of top surface  402  may be substantially negligible and/or may not cause a defect within annealed sapphire structure  400 , as discussed herein. The discrepancies in the configurations of the distinct terraced protrusion portions  410 ,  412 ,  414 ,  416 , and remaining portion  418  (e.g., unpatterened) may be cause by a plurality of factors including, but not limited to: the predetermined annealing temperature of the annealing process, the predetermined annealing time of the annealing process, the predetermined atmospheric pressure of the annealing process, the method of applying the heat, imperfections on top surface  402  of annealed sapphire structure  400 , and the crystallographic orientation of the surfaces (e.g., top surface  402 , sidewall  406 ,  408 ) of annealed sapphire structure  400 . 
     Turning to  FIG. 4B , a cross-sectional front view of terrace protrusions  410  of annealed sapphire structure  400  is shown according to embodiments. More specifically, a profile of terraced protrusions  410  and a portion of remaining portion  418  of top surface  402  is shown in  FIG. 4B . As discussed herein, the profile and/or configuration of top surface  402  including terraced protrusions  410 , as shown in  FIG. 4B , may be formed as a result of the moving of the surface atoms of annealed sapphire structure  400  during the annealing process. For reference, the substantially horizontal phantom line of  FIG. 4B-4G  may represent pre-annealing top surface  420  of annealed sapphire structure  400 . 
     Also shown in  FIG. 4B , annealed sapphire structure  400  may include a plane  422  having a crystallographic orientation. More specifically, plane  422  of annealed sapphire structure  400  may be substantially offset by an angle (θ) when compared to pre-annealing top surface  420  (shown in phantom). As discussed above, during the annealing process surface atoms may rearrange themselves in a configuration that requires the least amount of energy. As a result, each of the plurality of terraced protrusions  410  of top surface  402  may be in substantial alignment with plane  422  of annealed sapphire structure  400 . More specifically, and as shown in  FIG. 4B , a protrusion face  424  of each of the plurality of terraced protrusions  410  and a protrusion face  426  of the protrusions of remaining portion  418  may be in parallel alignment with plane  422 . The plane crystallographic orientation  422  may include any conventional plane of corundum (e.g., A-plane, C-plane, M-plane). 
     As discussed herein, the terraced protrusions formed in remaining portion  418  may include a substantially small height and peak-to-peak distance (hereafter, “peak distance”). By comparison, terraced protrusions  410  formed in top surface  402  may be substantially larger in both height and peak distance when compared to the terraced protrusions of remaining portion  418 . The configuration and/or dimensions of terraced protrusions  410  of top surface  402  may indicate that a defect is present within top surface  402  of annealed sapphire structure  400 . That is, and as discussed herein, because of the configuration of the terraced protrusions  410 , the portion of top surface  402  of annealed sapphire structure  400  including terraced protrusions  410  may require further inspection processes to determine if terraced protrusions  410  may cause a defect within annealed sapphire structure  400 . 
     As shown in  FIG. 4C , non-x-ray measuring device  428  (hereafter, “non-x-ray device”) may measure the profile of terraced protrusions  410  formed in a portion of top surface  402  of annealed sapphire structure  400 . Utilizing non-x-ray device  428  to measure the profile of terraced protrusions  410  of annealed sapphire structure  400  may correspond to operation  304  of  FIG. 3 . As discussed herein, the measuring of the profile by non-x-ray device  428  may include determining an actual height (H ACTL ) and actual peak-to-peak or peak distance (PD ACTL ) of the plurality of terraced protrusions  410  of the measured portion of top surface  402  of annealed sapphire structure  400 . As shown in  FIG. 4C , each of the plurality of terraced protrusions  410  formed in top surface  402  may include a peak  430 , which may be the highest point formed in terraced protrusions  410  during the annealing process. During the annealing process, the surface atoms that may form peak  430  may move the furthest from pre-annealing top surface  420  (shown in phantom) to allow face  424  of terraced protrusions  410  to be in substantial alignment with plane  422 . Additionally, each of the plurality of terraced protrusions  410  may also include a base point  432 , which may be in substantial alignment with pre-annealing top surface  420  (shown in phantom). Distinct from the atoms forming peak  430 , the surface atoms of that form base point  432  may move minimally, or not all, during the annealing process, and may remain in a substantially similar position as prior to the annealing of annealed sapphire structure  400 . The actual height (H ACTL ) of terraced protrusion  410  may be the distance between base point  432  and/or pre-annealing top surface  420  and peak  430 . Additionally, the actual peak distance (PD ACTL ) of terraced protrusions  410  of annealed sapphire structure  400  may be the distance between two distinct peaks  430 . As discussed herein, the actual height (H ACTL ) and/or the actual peak distance (PD ACTL ) of the terraced protrusion  410  formed in top surface  402  of sapphire structure  400  may be directly correlated to the presence of a defect within top surface  402  of annealed sapphire structure  400 . 
     As shown in  FIG. 4B  the actual height (H ACTL ) and the actual peak distance (PD ACTL ) for each of the protrusions of terraced protrusions  410  may be substantially similar and uniform. As such, the measured actual height (H ACTL ) of a single protrusion of terrace protrusions  410 , and the measured actual peak distance (PD ACTL ) between two protrusions of terrace protrusions  410  is shown in  FIG. 4B . However, it is understood that each of the plurality of terraced protrusions (e.g., terraced protrusions  410 ) formed on top surface  402  during an annealing process may be distinct from one another, which may require the measuring of most or substantially all terraced protrusion formed in top surface  402 . More specifically, each of the plurality of terraced protrusions may include a distinct actual height (H ACTL ) and/or actual peak distance (PD ACTL ). As such, the majority, if not all, of the plurality of terraced protrusions may be measured for completeness of inspecting annealed sapphire structure  400 . 
     Prior to measuring, non-x-ray device  428  may also be utilized to determine the protrusions of remaining portion  418  may not cause a potential defect within annealed sapphire structure  400 . More specifically, an intermediate process may be performed prior to the measuring of the profile of sapphire structure  400 . The intermediate process may include examining the substantially small protrusions of remaining portion  418 , and determining the protrusions of remaining portion  418  are negligible with respect to inspecting sapphire structure  400 . That is, because the terraced protrusions formed on remaining portion  418  are substantially small, there may be substantially no chance that the protrusions found in remaining portion  418  may include a defect. As discussed herein, because of the small configuration and/or dimensions of the protrusions of remaining portion  418 , and the subsequent determination that the protrusions of remaining portion  418  are negligible within respect to the inspection process, no additional inspection process may be performed on the protrusions of remaining portion  418 . As a result, the inspection of sapphire structure  400  may include a substantially reduced time and/or cost to the manufacturer of sapphire structure  400 . 
     As shown in  FIG. 4D , defect  434  may be identified as terraced protrusions  410  formed in a portion of top surface  402  of annealed sapphire structure  400 . More specifically, the plurality of protrusions of top surface  402  forming terraced protrusions  410  may be identified as defect  434  of sapphire structure  400 . The identifying of defect  434  in  FIG. 4D  may correspond to operation  306  of  FIG. 3 . As discussed herein, defect  434  of annealed sapphire structure  400  may include a substantially undesirable, optical defect formed in top surface  402 . More specifically, where defect  434  includes an optical defect caused by terraced protrusions (e.g., terraced protrusions  410 ) formed on top surface  402 , annealed sapphire structure  400  may include undesirable, colorful light reflections on surface  402  when sapphire structure  400  is exposed to light. 
     As shown in  FIG. 4D , and discussed herein, the identifying of defect  434  of annealed sapphire structure  400  may include comparing the actual height (H ACTL ) and peak distance (PD ACTL ) of the plurality of terraced protrusions  410  of top surface  402  with respective predetermined acceptable heights (H ACPT ) and predetermined acceptable peak distances (PD ACPT ). That is, the identifying of defect  434  may include comparing the actual height (H ACTL ) of the plurality of terraced protrusions  410  of top surface  402  with a predetermined acceptable height (H ACPT ) for sapphire structure  400 . Additionally, the identifying of defect  434  may include comparing the actual peak distance (PD ACTL ) of the plurality of terraced protrusions  410  of top surface  402  with a predetermined acceptable peak distance (PD ACPT ) for sapphire structure  400 . The predetermined acceptable height (H ACPT ) and the predetermined acceptable peak distance (PD ACPT ) may include a height and peak distance, respectively, of acceptable terraced protrusions  436  (shown in phantom) for annealed sapphire structure  400 . The acceptable terraced protrusions  436  for annealed sapphire structure  400  may include the upper-limit dimensions for terraced protrusions formed during the annealing process, where acceptable terraced protrusions  436  of top surface  402 , and ultimately annealed sapphire structure  400 , are substantially free from defect  434 . That is, acceptable terraced protrusions  436  may include dimensions that represent the maximum height (H) and peak distance (PD) for terraced protrusions formed on top surface  402  of annealed sapphire structure  400 , where annealed sapphire structure  400  may be free and/or may not include defect  434 . 
     The identifying of defect  434 , and more specifically, the comparing of the actual height (H ACTL ) and peak distance (PD ACTL ) with the predetermined acceptable heights (H ACPT ) and predetermined acceptable peak distances (PD ACPT ), respectively, may further include determining if the actual height (H ACTL ) and peak distance (PD ACTL ) differ from the predetermined acceptable heights (H ACPT ) and acceptable peak distances (PD ACPT ). That is, defect  434  may be identified in annealed sapphire structure  400  by comparing and determining if the actual height (H ACTL ) of terraced protrusions  410  differ from the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436 . Additionally, defect  434  may be identified in annealed sapphire structure  400  by comparing and determining if the actual peak distance (PD ACTL ) of terraced protrusions  410  differ from the predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusions  436 . As shown in  FIG. 4D , both the actual height (H ACTL ) and peak distance (PD ACTL ) of the terraced protrusions  410  formed on top surface  402  may be larger than or exceed the predetermined acceptable heights (H ACPT ) and acceptable peak distances (PD ACPT ), respectively. More specifically, when comparing the actual height (H ACTL ) of the terraced protrusions  410  with the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436  of annealed sapphire structure  400 , it may be determined that the actual height (H ACTL ) is larger than the predetermined acceptable heights (H ACPT ). Additionally, by comparing the actual peak distance (PD ACTL ) of the terraced protrusions  410  with the predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusions  436 , it may also be determined that the actual peak distance (PD ACTL ) is greater than the predetermined acceptable peak distance (PD ACPT ). As such, terraced protrusions  410  of top surface  402  may be identified as defect  434  within annealed sapphire structure  400 . As discussed herein, a portion or the entirety of annealed sapphire structure  400  may be further processed when defect  434  is identified, to remove or substantially correct defect  434  of annealed sapphire structure  400 . 
     In additional embodiments, terraced protrusions  412 ,  414 ,  416  formed in top surface  402  of annealed sapphire structure  400  may include distinct configurations or dimensions, which ultimately may or may not result in defect  434  of annealed sapphire structure  400 . 
     For example,  FIG. 4E  depicts a cross-sectional front profile view of the plurality of terraced protrusions  412  formed in top surface  402  of annealed sapphire structure  400 . It is understood that similarly numbered components may function in a substantially similar fashion. Redundant explanation of these components has been omitted for clarity. As shown in  FIG. 4E , Defect  434  may also be identified in terraced protrusions  412  formed in top surface  402 . However, the identifying of defect  434  in terraced protrusions  412  may be distinct from the identifying of defect  434  within terraced protrusions  410  ( FIGS. 4A and 4D ). More specifically, the configuration or dimensions of terraced protrusions  412  may be distinct from terraced protrusions  410  ( FIGS. 4A and 4D ), which may ultimately cause the identifying of defect  434  of annealed sapphire structure  400  to be distinct as well. The identifying of defect  434  in terraced protrusion  412  may be performed in a substantially similar manner as discussed with respect to  FIG. 4D . However, because of terraced protrusions  412  distinct configuration or dimensions when compared to terraced protrusions  410 , the outcome of the identifying process may be distinct. For example, and with comparison to the identifying of defect  434  within terraced protrusions  410  ( FIG. 4D ), the actual height (H ACTL ) of peaks  430  for terraced protrusions  412  may be compared to the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436  of annealed sapphire structure  400 . In comparing the respective heights (e.g., H ACTL , H ACPT ), it may be determined that the actual height (H ACTL ) of terraced protrusions  412  differs from the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436 . More specifically, it may be determined that the actual height (H ACK ) of terraced protrusions  412  is larger than the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436 . However, in comparing the actual peak distance (PD ACTL ) of terraced protrusions  412  and the predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusions  436 , it may be determined that the respective peak distances (e.g., PD ACTL , PD ACPT ) are substantially equal to one another. That is, the actual peak distance (PD ACTL ) of terraced protrusions  412  and the predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusion  436  may be substantially equal. Where the actual peak distance (PD ACTL ) and the predetermined acceptable peak distance (PD ACPT ) are substantially equal, the actual peak distance (PD ACTL ) of terraced protrusion  412  may not be attributed to the cause of defect  434  in annealed sapphire structure  400 . As a result, in the embodiment shown in  FIG. 4E , only the actual height (H ACTL ), and not the actual peak distance (PD ACTL ), of terraced protrusion  412  may be attributed to causing defect  434  within annealed sapphire structure  400 . As discussed herein, where defect  434  is attributed only to the actual height (H ACTL ) of terraced protrusions (e.g., terraced protrusions  412 ) formed in top surface  402  of annealed sapphire structure  400 , specific additional processes may be performed on annealed sapphire structure  400  to substantially correct defect  434 . 
     In an additional embodiment, as shown in  FIG. 4F , the converse to the embodiment discussed with respect to  FIG. 4E  may be shown. More specifically,  FIG. 4F  shows a cross-sectional front profile view of the plurality of terraced protrusions  414  formed in top surface  402  of annealed sapphire structure  400 . Terraced protrusions  414  of annealed sapphire surface  400  may include defect  434  identified using similar processes as discussed above. However, and with comparison to terraced protrusions  412  shown in  FIG. 4E , defect  434  may be identified as a result of a distinct outcome of the identifying process. In comparing the respective heights (e.g., H ACTL , H ACPT ), it may be determined that the actual height (H ACTL ) of terraced protrusions  414  differs from the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436 . More specifically, it may be determined that the actual height (H ACTL ) of terraced protrusions  414  is smaller than the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436 . Because, the actual height (H ACTL ) of terraced protrusions  414  is smaller than the predetermined acceptable heights (H ACPT ) (e.g., maximum acceptable height), the actual height (H ACTL ) of terraced protrusions  414  may not be attributed to the cause of defect  434  in annealed sapphire structure  400 . However, in comparing the actual peak distance (PD ACTL ) of terraced protrusions  414  and the predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusions  436 , it may be determined that the respective peak distances (e.g., PD ACTL , PD ACPT ) substantially differ. That is, the actual peak distance (PD ACTL ) of terraced protrusions  412  is larger the predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusion  436 . As a result, in the embodiment shown in  FIG. 4F , only the actual peak distance (PD ACTL ), and not the actual height (H ACTL ), of terraced protrusion  414  may be attributed to causing defect  434  within annealed sapphire structure  400 . As discussed herein, where defect  434  is attributed only to the actual peak distance (PD ACTL ) of terraced protrusions (e.g., terraced protrusions  414 ) formed in top surface  402  of annealed sapphire structure  400 , specific additional processes may be performed on annealed sapphire structure  400  to substantially correct defect  434 . 
     In a further embodiment, as shown in  FIG. 4G , terraced protrusions  416  formed on top surface  402  of annealed sapphire structure  400  may not include defect  434  ( FIGS. 4D-4F ).  FIG. 4G  shows a cross-sectional front profile view of the plurality of terraced protrusions  416  formed in top surface  402  of annealed sapphire structure  400 . Terraced protrusions  416  of annealed sapphire surface  400  may not include defect  434  like the distinct terraced protrusions  410 ,  412 ,  414  of annealed sapphire structure  400 . The identifying processes discussed herein may be used to determine that terraced protrusions  416  may not include defect  434 . More specifically, the actual height (H ACTL ) and peak distance (PD ACTL ) of terraced protrusions  416  may be compared with the predetermined acceptable heights (H ACPT ) and predetermined acceptable peak distances (PD ACPT ), respectively, of acceptable terraced protrusion  436  of annealed sapphire structure  400 . As shown in  FIG. 4G , it may also be determined that the actual height (H ACTL ) and peak distance (PD ACTL ) of terraced protrusions  416  differ from the predetermined acceptable heights (H ACPT ) and acceptable peak distances (PD ACPT ). That is, the actual height (H ACTL ) of terraced protrusions  416  may be smaller than, or within the maximum acceptable dimensions, as defined by the predetermined acceptable heights (H ACPT ) of acceptable terraced protrusions  436  of annealed sapphire structure  400 . Similarly, the actual peak distance (PD ACTL ) of terraced protrusions  416  may also be smaller than, or within the maximum acceptable dimensions, as defined by the predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusions  436 . As a result, the identifying process discussed herein may determine that terraced protrusions  416  of annealed sapphire structure  400  do not include defect  434  ( FIG. 4D-4F ). As such, terraced protrusions  416  may not require further processing, and may be acceptable for annealed sapphire structure  400  to be utilized within electronic device  10  ( FIG. 1 ). 
     As discussed herein, as a result of being able to identify defect  434  in the top surface  402  of the sapphire structure  400  using a non-x-ray based measuring device  428 , sapphire structures  400  may be inspected more easily, more quickly and more cost-effectively, than conventional ways which include x-ray measuring devices. Additionally, each individual sapphire structure  400  may be inspected using the method discussed herein. By inspecting the sapphire structures  400  using the methods described herein, manufacturers may be able to improve quality control of the sapphire structure  400 , and/or may examine every sapphire structure  400  before it is implemented in its final function (e.g., screen for electronic device  10 ). 
     The use of non-x-ray device  428  may also help indicate that sapphire structures  400  are being formed within a desired plane, or include an acceptable offset (e.g., θ) of a desired plane. That is, by identifying an orientation of face  424  of terraced protrusions  410 ,  412 ,  414 ,  416  non-x-ray device  428  may also aid in performing a quality control check as well. As discussed above, face  424  may formed in substantial alignment with plane  422  of sapphire structure  400 . Additionally, each sapphire structure  400  may be made with a desired plane or offset (e.g., θ) of a desired plane in order to be acceptable for use within electronic device  10  ( FIG. 1 ). Typically, these planes are measure on a large piece of grown corundum using an x-ray diffraction methods, and not the plurality of sapphire structures  400  formed from the grown corundum. This minimal check of orientation may be a result of the cost and time associated with x-ray diffraction. However, by utilizing non-x-ray device  428 , each sapphire structure  400  formed form the grown corundum may be inspected. Specifically, by determining the desired crystallographic plane orientation of the corundum using initial x-ray diffraction methods, non-x-ray device  428  may examine and compare the desired crystallographic plane orientation of the corundum and the orientation of face  424  of terraced protrusions  410  to determine if annealed sapphire structure  400  includes an crystallographic orientation in alignment with the desired crystallographic orientation. That is, as discussed herein, face  424  of terraced protrusions  410  may align itself with the crystallographic orientation of sapphire structure  400 . Therefore, the orientation of face  424  is substantially similar to the orientation of annealed sapphire structure  400 . As such, where orientation of face  424  is compared to, and differs drastically from the desired crystallographic plane orientation of the corundum, it may be determined that sapphire structure  400  is being formed within an undesirable crystallographic plane orientation. As such, processes of forming sapphire structure  400  (e.g., grinding, lapping, cutting) may require adjustments, so face  424  of terraced protrusions  410 ,  412 ,  414 ,  416  of annealed sapphire structure  400  are substantially equal to the desired plane. 
     Turning to  FIGS. 5-6H , a method for forming sapphire structure  600  may now be discussed. Specifically,  FIG. 5  is a flowchart depicting one sample method  500  for forming sapphire structure  600 .  FIGS. 6A-6H  may depict a side cross-sectional view of various portions of sapphire structure  600  undergoing method  500 , as depicted in  FIG. 5 . It is understood that similarly numbered components may function in a substantially similar fashion. Redundant explanation of these components has been omitted for clarity. 
     In operation  502 , at least top surface  602  of sapphire structure  600  may be treated. As shown in  FIG. 6A , a cross-sectional front view of a portion of sapphire structure  600  is shown. The process of treating sapphire structure  600  may be depicted in  FIG. 6A . The process of treating at least top surface  602  of sapphire structure  600  in operation  502  may include lapping sapphire structure  600  and polishing lapped top surface  602  of sapphire structure  600 . As shown in  FIG. 6A , a polishing process being performed on sapphire structure  600  is depicted. Sapphire structure  600  may be previously lapped, such that sapphire structure  600  may include a substantially desired thickness. As shown in  FIG. 6A , top surface  602  of sapphire structure  600  may be substantially non-uniform and may include a plurality of ridges  640 . The plurality of ridges  640  may be formed during the lapping process of sapphire structure  600 . The polishing process performed on sapphire structure  600  may substantially remove the plurality of ridges  640 . More specifically, as shown in  FIG. 6A , polishing device  642  may perform a polishing process on sapphire structure  600  for substantially removing the plurality of ridges  640  formed during a lapping process and configuring top surface  602  to include a substantially linear surface. The treating process of operation  502  may include any conventional lapping and/or polishing techniques typically used in the formation of sapphire structure  600 . More specifically, the lapping techniques may include, but are not limited to grinding-lapping, or soft-material lapping, and the polishing techniques may include, but are not limited to chemical mechanical polishing, flame polishing, or vapor polishing. 
     As shown in  FIG. 6A , the treating of top surface  602  of sapphire structure  600  in operation  502  may cause a plurality of imperfections  644  in top surface  602 . More specifically, during the lapping and/or the polishing process performed on top surface  602  of sapphire structure  600  may cause imperfections  644 , such as cracks  646  and/or gaps  648 , to be formed in sapphire structure  600 . The cracks  646  and/or gaps  648  may be formed in top surface  602  and may extend partially through sapphire structure  600 . As discussed herein, annealing sapphire structure  600  may aid in healing and/or fixing these imperfections  644  (e.g., cracks  646 , gaps  648 ) in sapphire structure  600 . 
     In operation  504 , treated sapphire structure  600  may be annealed. As shown in  FIG. 6B , sapphire structure  600  may undergo an annealing process. More specifically, sapphire structure  600  may be exposed to a predetermined annealing temperature, for a predetermined annealing time, in a predetermined annealing atmospheric pressure to substantially anneal sapphire structure  600 . The annealing process of operation  504  may be performed on sapphire structure  600  to heal and/or correct imperfections  644  (e.g., cracks  646 , gap  648 ). That is, with comparison to  FIGS. 6B and 6C , annealing process of operation  504  may substantially heal and/or correct imperfections  644  formed on sapphire structure  600  during the treating process in operation  502 .  FIG. 6C  may depict sapphire structure  600  after the annealing process of operation  504  is complete. As discussed in detail above, during the annealing process, the surface atoms of sapphire structure  600  may be substantially mobile, such that the surface atoms rearrange themselves to heal or correct imperfections  644  of sapphire structure  600 . Additionally as discussed in detail above, and shown in  FIG. 6C , the surface atoms of sapphire structure  600  may substantially rearrange themselves to formed terraced protrusions  610  in top surface  602  of sapphire structure  600 . That is, the annealing of sapphire structure  600  may include forming the plurality of distinct terrace protrusions  610  on top surface  602  of sapphire structure  600 , as discussed herein. 
     In operation  506 , at least a portion of top surface  602  of sapphire structure  600  may be inspected using non-x-ray based measuring device  628 . As shown in  FIG. 6D , and as similarly discussed with reference to  FIGS. 3-4G  above, non-x-ray device  628  may be utilized to inspect a profile of sapphire structure  600 . The inspection of top surface  602  of sapphire structure  600  in operation  506  may include similar processes as discussed above. More specifically, the inspection of top surface  602  in operation  506  may include measuring a profile of top surface  602  of sapphire structure  600  after the annealing process. The measuring of the profile of top surface  602  may include determining an actual height (H ACTL ) of terraced protrusions  610 , and determining an actual peak distance (PD ACTL ) between peaks  630  of terraced protrusions  610 , as discussed above. 
     In operation  508 , defect  634  may be identified in the inspected portion of top surface  602  of sapphire structure  600 . Returning to  FIG. 6D , defect  634  may be identified using substantially similar processes as discussed above. That is, the identifying of defect  634  in sapphire structure  600  may include comparing the actual height (H ACTL ) and peak distance (PD ACTL ) of terraced protrusions  610  with the predetermined acceptable height (H ACPT ) and predetermined acceptable peak distance (PD ACPT ) of acceptable terraced protrusions  636  (shown in phantom) of sapphire structure  600 . Additionally, in comparing the respective heights (e.g., H ACTL , H ACPT ) and peak distances (PD ACTL , PD ACPT ), the identifying may also include determining if the actual height (H ACTL ) and peak distance (PD ACTL ) differ from the predetermined acceptable height (H ACPT ) and peak distance (H ACPT ), respectively. As discussed herein, where the actual height (H ACTL ) and peak distance (PD ACTL ) differ from, and more specifically exceed the predetermined acceptable height (H ACPT ) and peak distance (P DACPT ), defect  634  may be included in terraced protrusions  610  of sapphire structure  600 . 
     As shown in  FIG. 6D , both the actual height (H ACTL ) and peak distance (PD ACTL ) of terraced protrusions  610  exceed the respective predetermined acceptable height (H ACPT ) and peak distance (P DACPT ) of acceptable terraced protrusion  636  of sapphire structure  600 . As such, further processing (e.g., operations  510  and/or  512 ) may be performed on sapphire structure  600 . As discussed herein, where the actual height (H ACTL ) and peak distance (PD ACTL ) of terraced protrusions  610  do not differ or exceed the respective predetermined acceptable height (H ACPT ) and peak distance (P DACPT ) of acceptable terraced protrusion  636  of sapphire structure  600 , final, cosmetic processes (e.g., operation  514 ) may be performed on sapphire structure  600 . 
     In operation  510 , top surface  602  of sapphire structure  600  may be re-treated in response to identifying defect  634  in sapphire structure  600  in operation  508 . As shown in  FIG. 6E , after identifying defect  634  ( FIG. 6D ) in sapphire structure  600  in operation  508 , sapphire structure may be re-treated, or undergo at least some of the treating processes discussed in operation  502  again. That is, sapphire structure  600  may be re-lapped and/or re-polished again, such that terraced protrusions  610  formed during the annealing process in operation  504  may be substantially lapped and/or or polished. As shown in  FIG. 6E , terraced protrusions  610  (shown in phantom) may be substantially removed from sapphire structure  600  as a result of re-treating top surface  602 . That is, terrace protrusions  610  may be removed from top surface  602  as a result of the re-treating process in operation  510 , where top surface  602  is substantially planar. As shown in  FIG. 6E , and discussed herein, the re-treating process in operation  510  may cause additional imperfections  644  in sapphire structure  600 . More specifically, the re-treating (e.g., lapping, polishing) of sapphire structure  600  to remove terraced protrusions  610  including defect  634  may also cause new imperfections  644 , such as crack  646 , in sapphire structure  600 . 
     In operation  512 , sapphire structure  600  may be re-annealed in response to identifying defect  634  in sapphire structure  600  in operation  508 , and/or re-treating top surface  602  in operation  510 . As shown in  FIGS. 6F and 6G , re-treated sapphire structure  600  may be re-annealed or annealed again as a result of identifying defect  634  in terraced protrusions  610  ( FIG. 6D ). However, the re-annealing process of operation  512  may be distinct from the annealing process in operation  504 , in that that the re-annealing process of sapphire structure  600  may include adjusting annealing operational characteristics. More specifically, during the re-annealing of sapphire structure  600  in operation  512 , at least one of the following annealing operational characteristics may be adjusted: the annealing temperature surrounding sapphire structure  600 , the annealing time for sapphire structure  600 , and/or the atmospheric pressure surrounding sapphire structure  600 . By adjusting at least one of the annealing operational characteristics, the mobility of the surface atoms of sapphire structure  600  may be directly affected, which may ultimately cause affect the configuration or formation of distinct terraced protrusions  616  formed during the re-annealing process of operation  512 . 
     For example,  FIG. 6E  may depict an re-annealing process performed on re-treated sapphire structure  600 , where the annealing time is substantially lower in the re-annealing process of operation  512  than the annealing time used in operation  504  (e.g.,  FIG. 6B ). As such, the surface atoms of top surface  602  of sapphire structure  600  may not have as much time to rearrange themselves during the re-annealing process of operation  512 . As a result of the adjustment to the annealing time and/or reduced rearrangement time for the surface atoms, terraced protrusions  616  formed in the re-annealing process, as shown in  FIG. 6F , may include an actual height (H ACTL ) and actual peak distance (PD ACTL ) substantially smaller than terraced protrusions  610  formed during the annealing process of operation  504  ( FIG. 6D ). Additionally, as a result of the adjustment of the annealing time during the re-annealing process in operation  512 , terraced protrusions  616  may be subsequently inspected (operation  508 ) to determine if defect  634  ( FIG. 6D ) is still identifiable within sapphire structure  600  (operation  508 ). As shown in the embodiment depicted in  FIG. 6E , terraced protrusions  616  of sapphire structure  600  may be substantially free from defect  634  ( FIG. 6D ). More specifically, the actual height (H ACK ) and peak distance (PD ACTL ) of terraced protrusions  616  do not exceed the respective predetermined acceptable height (H ACPT ) and peak distance (P DACPT ) of acceptable terraced protrusion  636  of sapphire structure  600 . As such, sapphire structure  600  including terraced protrusions  616  formed on top surface  602  during the re-annealing process of operation  512  may be substantially free from defect  634  and may be acceptable for use within electronic device  10  ( FIG. 1 ). 
     In operation  514 , at least one decorative layer  650  may be deposited over at least a portion of re-treated, re-annealed sapphire structure  600 . As shown in  FIG. 6H , re-treated, re-annealed sapphire structure  600  include terraced protrusions  616  may include at least one deposited decorative layer  650 . More specifically, in operation  514  decorative layer  650  may be deposited over at least a portion of terraced protrusions  616  formed in top surface  602  of sapphire structure  600 . Decorative layer  650  may include paint, etching material, graphics, or any other conventional layer that may be deposited on at least a portion of top surface  602  including terraced protrusions  616  prior to sapphire structure  600  being implemented within electronic device  10  ( FIG. 1 ). Decorative layer  650  may be deposited over at least a portion of top surface  602  of sapphire structure  600  using any conventional deposition technique including, but not limited to: chemical vapor deposition, spin coating, sputtering, or pulsed laser deposition. 
     As shown in  FIG. 5 , and discussed above, where defect  634  is not identified in top surface  602  of sapphire structure  600 , at least one decorative layer  650  may be deposited on sapphire structure  600 . That is, in an additional embodiment (not shown), sapphire structure  600  may not include defect  634  after performing the annealing process in operation  504 . More specifically, and as similarly discussed with respect to annealed sapphire structure  400  in  FIG. 4G , sapphire structure  600  may be substantially free from defect after performing the annealing process in operation  504 . As such, while performing the inspection process in operation  506 , and the identifying process in operation  508 , it may be determined that sapphire structure  600  is substantially free from and/or may not include defect  634 . As a result, sapphire structure  600 , free from defect  634 , may subsequently skip operation  510  and/or operation  512 , and may proceed to the depositing of decorative layer  550  in operation  514 . 
     Additionally as shown in  FIG. 5 , after defect  634  is identified in operation  508 , operation  510  may be performed. However, operation  512  may or may not be performed before repeating the inspection process of operation  506 . That is, and distinct from the discussion above with respect to  FIGS. 6A-6H , top surface  602  of sapphire structure  600  including defect  634  may be re-treated in operation  510 , and then may be subsequently re-inspected in operation  506 , without re-annealed sapphire structure  600  in operation  512 . The specific configuration or dimensional orientation of terraced protrusions  610  including defect  634  may determine if sapphire structure  600  may require re-annealing before being re-inspected. That is, the actual height (H ACTL ) and/or the actual peak distance (PD ACTL ) of terraced protrusions  610  may determine if the re-annealing of operation  512  may be performed. As discussed above with respect to  FIGS. 6A-6H , where both the actual height (H ACTL ) and peak distance (PD ACTL ) of terraced protrusions  610  exceed the respective predetermined acceptable height (H ACPT ) and peak distance (PD ACPT ) of acceptable terraced protrusion  636 , the re-annealing process of operation  512  may be performed on sapphire structure  600 . Similarly, where only the actual peak distance (PD ACTL ) of terraced protrusions  610  exceeds the predetermined peak distance (PD ACPT ) of acceptable terraced protrusion  636 , the re-annealing process of operation  512  may be performed on sapphire structure  600 . However, where only the actual height (H ACTL ) of terraced protrusions  610  exceeds the predetermined height (H ACPT ) of acceptable terraced protrusion  636 , the re-annealing process of operation  512  may not be performed on sapphire structure  600 . As discussed above with respect to  FIG. 4E , where only the actual height (H ACTL ) of terraced protrusions  610  exceeds the predetermined height (H ACPT ) of acceptable terraced protrusion  636 , defect  634  may only be attributed to the height (H) of terraced protrusions  610 . As such, the re-treating of sapphire structure  600  in operation  510  alone may correct defect  634 . More specifically, by lapping and/or polishing off a top portion of terraced protrusions  610  of sapphire structure  600 , terraced protrusions  610  may no longer include defect  634 , and may be implemented within electronic device  10  ( FIG. 1 ). 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. They are not target to be exhaustive or to limit the embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings.

Metadata:
Filing Date: 20140207
Publication Date: 20180109
Grant Date: 20180109
Priority Date: 20140207
Inventors: MEMERING DALE N.
ROGERS MATTHEW S.
MYERS SCOTT A.
Assignee: APPLE INC
CPC Classifications: [{"code": "G01N33/385", "inventive": true, "first": true, "tree": "[]"}, {"code": "G01B21/20", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01N21/958", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01N33/39", "inventive": true, "first": true, "tree": "[]"}, {"code": "G01N33/39", "inventive": true, "first": true, "tree": "[]"}, {"code": "G01B21/20", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01N21/958", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01N21/958", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01B21/20", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 53774721