公开(公告)号：US11446771B2

公开(公告)日：2022-09-20

申请号：US16685393

申请日：2019-11-15

Applicant: DISCO CORPORATION

Inventor： Ryohei Yamamoto

IPC: H01L29/16 ,  B23K26/53 ,  B23K26/00 ,  B23K26/02 ,  B23K103/00 ,  B23K101/40

Abstract: A wafer producing method for producing a wafer from an ingot, the ingot being previously formed with a separation layer along which the wafer is to be separated from the ingot. The wafer producing method includes a first ultrasonic vibration applying step of applying ultrasonic vibration to a given area of the ingot at a high density to thereby form a partially broken portion where a part of the separation layer is broken, a second ultrasonic vibration applying step of applying the ultrasonic vibration to the whole area of the ingot larger than the given area at a low density, after performing the first ultrasonic vibration applying step, thereby forming a fully broken portion where the separation layer is fully broken in such a manner that breaking starts from the partially broken portion, and a separating step of separating the wafer from the ingot along the fully broken portion.

公开(公告)号：US11114307B2

公开(公告)日：2021-09-07

申请号：US16365014

申请日：2019-03-26

Applicant: DISCO CORPORATION

Inventor： Ryohei Yamamoto

IPC: H01L21/322 ,  B23K26/00 ,  H01L21/78 ,  B28D5/00 ,  B23K26/53

Abstract: A method of producing a wafer includes a peel-off layer forming step to form a peel-off layer in a hexagonal single-crystal ingot by applying a laser beam having a wavelength transmittable through the hexagonal single-crystal ingot while positioning a focal point of the laser beam in the hexagonal single-crystal ingot at a depth corresponding to the thickness of a wafer to be produced from an end face of the hexagonal single-crystal ingot, an ultrasonic wave generating step to generate ultrasonic waves from an ultrasonic wave generating unit positioned in facing relation to the wafer to be produced across a water layer interposed therebetween, thereby to break the peel-off layer, and a peel-off detecting step to detect when the wafer to be produced is peeled off the hexagonal single-crystal ingot by positioning an image capturing unit sideways of the wafer to be produced.

公开(公告)号：US11358306B2

公开(公告)日：2022-06-14

申请号：US16199576

申请日：2018-11-26

Applicant: DISCO CORPORATION

Inventor： Kazuyuki Hinohara ,  Ryohei Yamamoto

IPC: B28D5/00 ,  B23K26/364 ,  B23K20/233 ,  B23K26/0622 ,  B28D5/04 ,  B23K26/00 ,  B23K26/08 ,  B23K20/10 ,  B23K26/53 ,  B23K26/70 ,  B23K103/00 ,  B23K101/40

Abstract: A peeling apparatus includes: an ingot holding unit holding an ingot with an ingot portion corresponding to a wafer being faced up; an ultrasonic wave oscillating unit which has an end face facing the ingot portion corresponding to the wafer and oscillates an ultrasonic wave; a water supplying unit supplying water to an area between the ingot portion corresponding to the wafer and the end face of the ultrasonic wave oscillating unit; and a peeling unit that holds the ingot portion corresponding to the wafer with suction and peels off the wafer from the ingot.

公开(公告)号：US10886127B2

公开(公告)日：2021-01-05

申请号：US16299445

申请日：2019-03-12

Applicant: DISCO CORPORATION

Inventor： Ryohei Yamamoto ,  Kazuyuki Hinohara

IPC: H01L21/02 ,  H01L21/66 ,  H01L21/67 ,  B23K26/00 ,  B24B37/00

Abstract: A method of producing a wafer includes forming a peel-off layer in a hexagonal single-crystal ingot by applying a laser beam having a wavelength transmittable through the ingot while positioning a focal point of the laser beam in the ingot at a depth corresponding to the thickness of a wafer to be produced from an end face of the ingot, generating ultrasonic waves from an ultrasonic wave generating unit positioned in facing relation to the wafer to be produced across a water layer interposed therebetween, thereby to break the peel-off layer, and detecting when the wafer to be produced is peeled off the ingot based on a change that is detected in the height of an upper surface of the wafer to be produced by a height detecting unit positioned above the upper surface of the wafer to be produced across the water wafer interposed therebetween.

公开(公告)号：US20180214976A1

公开(公告)日：2018-08-02

申请号：US15881180

申请日：2018-01-26

Applicant: DISCO CORPORATION

Inventor： Kentaro Iizuka ,  Koyo Honoki ,  Shuichi Torii ,  Yutaka Kobayashi ,  Ryohei Yamamoto ,  Kazuya Hirata

IPC: B23K26/00 ,  B23K26/38

Abstract: Disclosed herein is a laser processing apparatus for forming a separation layer inside an ingot by applying a laser beam to an end surface of the ingot in the condition where the focal point of the laser beam is set inside the ingot, the laser beam having a transmission wavelength to the ingot. The laser processing apparatus includes a holding unit for holding the ingot, a moving unit for moving the holding unit in a direction parallel to the end surface of the ingot held by the holding unit, a laser beam applying unit for applying the laser beam to the ingot held by the holding unit, an imaging unit for detecting the position of the ingot in the direction parallel to the end surface of the ingot, and a height detecting unit for detecting the height of the end surface of the ingot held by the holding unit.

公开(公告)号：US12296502B2

公开(公告)日：2025-05-13

申请号：US17805724

申请日：2022-06-07

Applicant: DISCO CORPORATION

Inventor： Koyo Honoki ,  Ryohei Yamamoto

IPC: B28D5/00 ,  B08B1/12 ,  B08B1/32 ,  B23K26/53 ,  B23K103/00

Abstract: There is provided a peeling apparatus including an ingot holding unit that has a holding surface for holding an ingot, a wafer holding unit that is capable of approaching and separating from the ingot holding unit and has a holding surface for holding under suction a wafer to be produced, and a cleaning brush that cleans peel-off surfaces at which the wafer to be produced has been peeled off from the ingot and thereby removes peeling swarf.

公开(公告)号：US11273522B2

公开(公告)日：2022-03-15

申请号：US16563282

申请日：2019-09-06

Applicant: DISCO CORPORATION

Inventor： Ryohei Yamamoto ,  Kazuya Hirata

IPC: B23K26/364 ,  B28D5/00 ,  B24B1/00 ,  B23K103/00

Abstract: A wafer producing method includes a facet area detecting step of detecting a facet area from an upper surface of an SiC ingot, a coordinates setting step of setting the X and Y coordinates of plural points lying on the boundary between the facet area and a nonfacet area in an XY plane, and a feeding step of setting a focal point of a laser beam having a transmission wavelength to SiC inside the SiC ingot at a predetermined depth from the upper surface of the SiC ingot, the predetermined depth corresponding to the thickness of the SiC wafer to be produced, next applying the laser beam from a focusing unit in a laser processing apparatus to the SiC ingot, and relatively moving the SiC ingot and the focal point in an X direction parallel to the X axis in the XY plane, thereby forming a belt-shaped separation layer extending in the X direction inside the SiC ingot.

公开(公告)号：US20180254223A1

公开(公告)日：2018-09-06

申请号：US15908307

申请日：2018-02-28

Applicant: DISCO CORPORATION

Inventor： Kazuya Hirata ,  Ryohei Yamamoto ,  Kunimitsu Takahashi

IPC: H01L21/66 ,  H01L21/02 ,  H01L21/268

CPC classification number: H01L22/12 ,  B23K26/032 ,  B23K26/0622 ,  B23K26/082 ,  B23K26/38 ,  B23K26/53 ,  B23K31/125 ,  B23K2103/56 ,  C30B29/36 ,  C30B29/406 ,  C30B33/02 ,  H01L21/0201 ,  H01L21/2686

Abstract: Disclosed herein is an inspecting method for a semiconductor ingot in which modified layers parallel to an upper surface of the ingot and cracks extending from each modified layer are previously formed as a separation start point. The inspecting method includes a light applying step of applying light from a light source to the upper surface of the ingot, the light impinging on the upper surface at a predetermined incidence angle, a projected image forming step of reflecting the light on the upper surface of the ingot to obtain reflected light and then forming a projected image from the reflected light, the projected image showing the emphasis of asperities generated on the upper surface of the ingot due to the formation of the modified layers and the cracks inside the ingot, an imaging step of detecting the projected image to form a detected image, and a determining step of comparing the detected image with preset conditions to determine the condition of the modified layers and the cracks.

公开(公告)号：US09975202B2

公开(公告)日：2018-05-22

申请号：US15678785

申请日：2017-08-16

Applicant: DISCO CORPORATION

Inventor： Ryohei Yamamoto ,  Kazuya Hirata

IPC: B23K26/08 ,  B28D5/00 ,  H01L21/02 ,  H01L31/00 ,  B23K26/00 ,  B23K26/53 ,  B23K103/00

CPC classification number: B23K26/0057 ,  B23K26/0006 ,  B23K26/032 ,  B23K26/0622 ,  B23K26/0823 ,  B23K26/0853 ,  B23K26/53 ,  B23K2101/40 ,  B23K2103/56 ,  B28D5/0011

Abstract: An SiC wafer is generated from an SiC ingot by a peel-off plane generating step for generating a peel-off plane by forming a separation layer made up of a modified layer, and cracks extending from the modified layer along a c-plane, a plurality of times by indexing-feeding a focused point of a pulsed laser beam and the SiC ingot relative to each other in a direction in which an off-angle is formed, thereby forming a plurality of separation layers to generate the peel-off plane. The peel-off plane generating step includes relatively moving the focused point from an end to an opposite end of the SiC ingot in a forward stroke and relatively moving the focused point from the opposite end to the end of the SiC ingot in a backward stroke to trace back the separation layer that has already been formed in the forward stroke.

公开(公告)号：US11726040B2

公开(公告)日：2023-08-15

申请号：US17649714

申请日：2022-02-02

Applicant: DISCO CORPORATION

Inventor： Kazuki Mori ,  Ryohei Yamamoto

IPC: G01N21/64

CPC classification number: G01N21/643 ,  G01N2021/6471

Abstract: A detecting apparatus for use in specifying regions having different impurity concentrations in an ingot includes an ingot holding unit having a holding surface for holding the ingot thereon, an excitation light source for applying excitation light having a predetermined wavelength to a face side of the ingot held on the holding surface, and a photodetector for detecting fluorescence emitted from the ingot upon exposure to the excitation light and generating an electric signal representing a number of photons of only light whose wavelength is in an infrared radiation range, of the detected fluorescence.