# US 2013/0252402 A1 · Laser processing method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0252402 A1 - Document ID: US20130252402A1 - Status: Published application - Kind: A1 - Application number: 13/614,042 - Filed: 2012-09-13 - Published: 2013-09-26 - Earliest claimed: 2002-03-12 - Assignees: Hamamatsu Photonics K.K. - Inventors: Fumitsugu FUKUYO; Kenshi FUKUMITSU - Web page: https://patentgrep.com/patent/US20130252402A1 ## CPC - H10P 54/00: Cutting or separating of wafers, substrates or parts of devices - B23K 26/40: taking account of the properties of the material involved - B23K 26/53: for modifying or reforming the material inside the workpiece, e.g. for producing break initiation cracks - B28D 1/221: {by thermic methods} - B28D 5/0011: {with preliminary treatment, e.g. weakening by scoring} - C03B 33/0222: {Scoring using a focussed radiation beam, e.g. laser} - C03B 33/033: Apparatus for opening score lines in glass sheets - C03B 33/07: Cutting armoured, {multi-layered, coated} or laminated, glass products - C03B 33/074: {Glass products comprising an outer layer or surface coating of non-glass material} - B23K 2101/40: Semiconductor devices - B23K 2103/50: {Inorganic materials other than metals or composite materials} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM - B28D: WORKING STONE OR STONE-LIKE MATERIALS - C03B: MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES ## Abstract A laser processing method which can highly accurately cut objects to be processed having various laminate structures is provided. An object to be processed comprising a substrate and a laminate part disposed on the front face of the substrate is irradiated with laser light L while a light-converging point P is positioned at least within the substrate, so as to form a modified region due to multiphoton absorption at least within the substrate, and cause the modified region to form a starting point region for cutting. When the object is cut along the starting point region for cutting, the object 1 can be cut with a high accuracy. ## Claims ### Claim at position 1 1-13. (canceled) ### Claim 14 A laser processing method comprising the steps of: irradiating an object to be processed comprising a substrate and a laminate part disposed on a front face of the substrate with laser light while positioning a light-converging point at least within the substrate, thereby forming a modified region embedded within the substrate along each line of a plurality of cutting lines arranged in a grid with respect to the substrate, each substrate modified region forming a starting point region for cutting the object inside the object at a predetermined distance from a laser light incident face of the object; and after completion of forming the substrate modified regions, applying a stress to the object which causes cutting of the substrate and the laminate part along the cutting lines thereby generating a fracture in a thickness direction of the substrate from each starting point region that reaches a front face of the laminate part and a rear face of the substrate, wherein after the irradiation of the laser light is performed, each substrate modified region exists only within the substrate, and wherein the at least one of the front and back face of the substrate is a surface of the substrate into which the laser light enters. ### Claim 15 A laser processing method comprising the steps of: irradiating an object to be processed comprising a substrate and a laminate part disposed on a front face of the substrate with laser light while positioning a light-converging point within the substrate, irradiating the object with laser light while positioning a light-converging point within the laminate part, thereby forming a modified region embedded within the substrate and a laminate part modified region embedded within the laminate part along each line of a plurality of cutting lines, each of the substrate modified regions and the laminate part modified regions forming a starting point region for cutting the object inside the object at a predetermined distance from a laser light incident face of the object; and cutting the substrate and the laminate part along the cutting lines when a fracture generated in a thickness direction of the substrate from each starting point region reaches a front face of the laminate part and a rear face of the substrate; wherein the substrate modified regions formed embedded within the substrate and the laminate part modified regions formed embedded within the laminate part are separate from each other, wherein after the irradiation of the laser light is performed, each substrate modified region exists only within the substrate, and wherein the at least one of the front and back face of the substrate is a surface of the substrate into which the laser light enters. ### Claim 16 A laser processing method comprising the steps of: irradiating a substrate with laser light while positioning a light-converging point within the substrate, thereby forming a modified region only within the substrate along each line of a plurality of cutting lines, each modified region forming a starting point region for cutting the substrate inside the substrate at a predetermined distance from a laser light incident face of the substrate; and providing a laminate part on a front face of the substrate after forming the starting point regions; and cutting the substrate and the laminate part along the cutting lines when a fracture generated in a thickness direction of the substrate from each starting point region reaches a front face of the laminate part and a rear face of the substrate, wherein after the irradiation of the laser light is performed, each substrate modified region exists only within the substrate, and wherein the at least one of the front and back face of the substrate is a surface of the substrate into which the laser light enters. ### Claim 17 A method of manufacturing a semiconductor device formed using a laser processing method, the manufacturing method comprising: irradiating an object to be processed comprising a substrate and a laminate part disposed on a front face of the substrate, the substrate and the laminate part having at least one semiconductor device, with laser light while positioning a light-converging point at least within the substrate, thereby forming a modified region embedded within the substrate along each line of a plurality of cutting lines arranged in a grid with respect to the substrate, each substrate modified region forming a starting point region for cutting the object, each substrate modified region being located inside the object at a predetermined distance from a laser light incident face of the object; and after completion of forming the substrate modified regions, applying a stress to the object causing cutting of the substrate and the laminate part along the cutting lines thereby generating a fracture in a thickness direction of the substrate from each starting point region that reaches a front face of the laminate part and a rear face of the substrate, wherein completion of the cutting step results in provision of at least one manufactured semiconductor device, wherein after the irradiation of the laser light is performed, each substrate modified region exists only within the substrate, and wherein the at least one of the front and back face of the substrate is a surface of the substrate into which the laser light enters. ### Claim 18 A method of manufacturing a semiconductor device formed using a laser processing method, the manufacturing method comprising: irradiating an object to be processed comprising a substrate and a laminate part disposed on a front face of the substrate, the substrate and the laminate part having at least one semiconductor device, with laser light while positioning a light-converging point within the substrate, irradiating the object with laser light while positioning a light-converging point within the laminate part, thereby forming a modified region embedded within the substrate and a laminate part modified region embedded within the laminate part along each line of a plurality of cutting lines, each of the substrate modified region and the laminate part modified region forming a starting point region for cutting the object located inside the object at a predetermined distance from a laser light incident face of the object; and cutting the substrate and the laminate part along the cutting lines when a fracture generated in a thickness direction of the substrate from each starting point region reaches a front face of the laminate part and a rear face of the substrate, wherein completion of the cutting step results in provision of at least one manufactured semiconductor device; wherein the substrate modified regions formed embedded within the substrate and the laminate part modified regions formed embedded within the laminate part are separate from each other, wherein after the irradiation of the laser light is performed, each substrate modified region exists only within the substrate, and wherein the at least one of the front and back face of the substrate is a surface of the substrate into which the laser light enters. ### Claim 19 A method of manufacturing a semiconductor device formed using a laser processing method, the manufacturing method comprising: irradiating a substrate with laser light while positioning a light-converging point within the substrate, thereby forming a substrate modified region only within the substrate along each line of a plurality of cutting lines, each modified region forming a starting point region for cutting the substrate, each modified region being located only inside the substrate at a predetermined distance from a laser light incident face of the substrate; providing a laminate part on a front face of the substrate after forming the starting point regions; and cutting the substrate and the laminate part along the cutting lines when a fracture generated in a thickness direction of the substrate from each starting point region reaches a front face of the laminate part and a rear face of the substrate, wherein completion of the cutting step results in provision of at least one manufactured semiconductor device, wherein after the irradiation of the laser light is performed, each substrate modified region exists only within the substrate, and wherein the at least one of the front and back face of the substrate is a surface of the substrate into which the laser light enters. ### Claim 20 (depends on 14) The laser processing method according to claim 14, wherein the modified region is formed due to multiphoton absorption. ### Claim 21 (depends on 14) The laser processing method according to claim 14, wherein the object is irradiated with the laser light while positioning the light-converging point at least within the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 μs or less and the modified region includes a crack region. ### Claim 22 (depends on 14) The laser processing method according to claim 14, wherein the object is irradiated with the laser light while positioning the light-converging point at least within the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 μs or less, and the modified region includes a molten processed region. ### Claim 23 (depends on 14) The laser processing method according to claim 14, wherein the object is irradiated with the laser light while positioning the light-converging point at least within the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 ns or less, and the modified region includes a refractive index change region which is a region with a changed refractive index. ### Claim 24 (depends on 14) The laser processing method according to claim 14, wherein the object is irradiated with the laser light while positioning light-converging point at least with the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 μs or less. ### Claim 25 (depends on 14) The laser processing method according to claim 14, wherein the substrate is made of piezoelectric material and the object is irradiated with the laser light while positioning the light-converging point at least within the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 μs or less. ### Claim 26 (depends on 14) The laser processing method according to claim 14, wherein the substrate is made of a semiconductor material and the modified region includes a molten processed region. ### Claim 27 (depends on 17) The laser processing method according to claim 17, wherein the modified region is formed due to multiphoton absorption. ### Claim 28 (depends on 17) The laser processing method according to claim 17, wherein the object is irradiated with the laser light while positioning a light-converging point at least within the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 μs or less, and the modified region includes a molten processed region. ### Claim 29 (depends on 17) The laser processing method according to claim 17, wherein the object is irradiated with the laser light while positioning a light-converging point at least within the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 ns or less. ### Claim 30 (depends on 17) The laser processing method according to claim 17, wherein the modified region includes a molten processed region. ### Claim 31 (depends on 30) The method according to claim 30, wherein the object is irradiated with laser light while positioning a light-converging point at least with the substrate under a condition with a peak power density of at least 1×108 (W/cm2) at the light-converging point and a pulse width of 1 μs or less.