# US 2014/0193606 A1 · Sapphire component with residual compressive stress > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0193606 A1 - Document ID: US20140193606A1 - Status: Published application - Kind: A1 - Application number: 13/738,200 - Filed: 2013-01-10 - Published: 2014-07-10 - Earliest claimed: 2013-01-10 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Kelvin Kwong - Web page: https://patentgrep.com/patent/US20140193606A1 ## CPC - C04B 41/0081: {characterised by the subsequent cooling step} - B32B 3/266: {characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12} - C04B 41/0036: {Laser treatment (working by laser beam B23K26/00)} - C30B 29/20: Aluminium oxides - C30B 33/02: Heat treatment (C30B33/04, C30B33/06 take precedence) - H04M 1/0266: {for a display module assembly} - H04M 1/185: {Improving the shock resistance of the housing, e.g. by increasing the rigidity} - Y10T 29/49826: Assembling or joining - Y10T 428/24331: including nonapertured component - Y10T 428/24992: Density or compression of components - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - C30B: SINGLE-CRYSTAL GROWTH (by using ultra-high pressure, e.g. for the formation of diamonds, B01J3/06); UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL (zone-refining of metals or alloys C22B); PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (casting of metals, casting of other substances by the same processes or devices B22D; working of plastics B29; modifying the physical structure of metals or alloys C21D, C22F); SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (for producing semiconductor devices or parts thereof H10); APPARATUS THEREFOR - H04M: TELEPHONIC COMMUNICATION (circuits for controlling other apparatus via a telephone cable and not involving telephone switching apparatus G08) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A method comprises shaping an aluminum oxide ceramic material into a component for an electronic device. The component has first and second major surfaces. A selected region of one or both of the first and second major surfaces is heated to an annealing temperature. The selected region is then cooled below the annealing temperature, so that residual compressive stress is generated in the selected region. ## Claims ### Claim 1 A method comprising: shaping an aluminum oxide ceramic material into a sapphire component for an electronic device, the sapphire component having first and second major surfaces; heating a selected region of one or both of the first and second major surfaces of the sapphire component to an annealing temperature; and cooling the selected region of the sapphire component below the annealing temperature, such that residual compressive stress is generated in the selected region of the sapphire component. ### Claim 2 (depends on 1) The method of claim 1, further comprising assembling the sapphire component into the electronic device. ### Claim 3 (depends on 1) The method of claim 1, wherein shaping the aluminum oxide ceramic material comprises forming the sapphire component with a substantially single crystal plane orientation between the first and second major surfaces. ### Claim 4 (depends on 3) The method of claim 3, wherein the selected region of the sapphire component is prone to impact when assembled into the electronic device. ### Claim 5 (depends on 4) The method of claim 4, wherein the selected region of the sapphire component comprises a corner portion of a cover glass, when the sapphire component is assembled into the electronic device. ### Claim 6 (depends on 5) The method of claim 5, wherein the selected region of the sapphire component excludes a central portion of the cover glass, when the sapphire component is assembled into the electronic device. ### Claim 7 (depends on 6) The method of claim 6, wherein the selected region of the sapphire component comprises at least a portion of each of the first and second major surfaces. ### Claim 8 (depends on 1) The method of claim 1, wherein the selected region of the sapphire component excludes one of the first and second major surfaces. ### Claim 9 (depends on 1) The method of claim 1, further comprising defining a failure pattern in the sapphire component, based on the residual compressive stress generated in the selected region. ### Claim 10 (depends on 1) The method of claim 1, wherein heating the selected region of the sapphire component comprises laser heating one or both of the first and second major surfaces, in the selected region. ### Claim 11 (depends on 10) The method of claim 10, wherein cooling the selected region of the sapphire component comprises directing a jet of cooling fluid onto one or both of the first and second major surfaces, in the selected region. ### Claim 12 (depends on 11) The method of claim 11, wherein a substantially single crystal plane orientation is maintained between the first and second major surfaces of the sapphire component, throughout heating and cooling of the selected region. ### Claim 13 A cover glass component for an electronic device, the cover glass component comprising: a substantially single crystal aluminum oxide ceramic material having first and second major surfaces, the first and second major surfaces defining the cover glass component therebetween; a first portion of the cover glass component having a residual compressive stress induced therein; and a second portion of the cover glass component not having the residual compressive stress induced therein; wherein the first portion of the cover glass component in which the residual compressive stress is induced has greater residual compressive stress than the second portion of the cover glass component in which the residual compressive stress is not induced. ### Claim 14 (depends on 13) The cover glass component of claim 13, wherein the first portion of the cover glass component is more prone to impact than the second portion, when assembled into the electronic device. ### Claim 15 (depends on 13) The cover glass component of claim 13, wherein the first portion of the cover glass component comprises a corner region of the cover glass component, when assembled into the electronic device. ### Claim 16 (depends on 15) The cover glass component of claim 15, wherein the second portion of the cover glass component comprises a center region of the cover glass component, when assembled into the electronic device. ### Claim 17 (depends on 13) The cover glass component of claim 13, wherein the first portion of the cover glass component is adjacent an edge of the cover glass component and the second portion is spaced from the edge by the first portion. ### Claim 18 (depends on 13) A mobile device comprising a display in combination with the cover glass component of claim 13, wherein the display is visible through the cover glass component. ### Claim 19 A mobile electronic device comprising: a display; a sapphire cover glass component adjacent the display, the sapphire cover glass component having a first major surface adjacent the display, oriented toward an interior of the device, and a second major surface opposite the display, oriented toward an exterior of the device; wherein a residual compressive stress is induced in a selected region of the sapphire cover glass component, such that the selected region has greater residual compressive stress than another region of the sapphire cover glass component in which the residual compressive stress is not induced. ### Claim 20 (depends on 19) The mobile electronic device of claim 19, wherein the selected region of the sapphire cover glass component comprises a corner portion of one or both of the first and second major surfaces, in which the residual compressive stress is induced. ### Claim 21 (depends on 20) The mobile electronic device of claim 20, wherein the other region of the sapphire glass component comprises a central portion of one or both of the first and second major surfaces, in which the residual compressive stress is not induced. ### Claim 22 (depends on 19) The mobile electronic device of claim 19, wherein the selected region of the sapphire cover glass component in which the residual compressive stress is induced is more prone to impact when the mobile electronic device is dropped, as compared to the other region of the sapphire cover glass component in which the residual compressive stress is not induced. ### Claim 23 (depends on 19) The mobile electronic device of claim 19, wherein the selected region of the cover glass component comprises an aperture for an audio device.