公开(公告)号：US20240326165A1

公开(公告)日：2024-10-03

申请号：US18735595

申请日：2024-06-06

Applicant: DENSO CORPORATION

Inventor： Koichiro YASUDA ,  Ryota TAKAGI ,  Tomoki KAWAZU ,  Sodai NOMURA ,  Hideaki SHIRAI ,  Bahman SOLTANI ,  Shunsuke SOBAJIMA

IPC: B23K26/082 ,  B23K26/38

CPC classification number: B23K26/082 ,  B23K26/38

Abstract: A surface of one end side of an ingot in a height direction thereof is irradiated with a laser beam having a permeability to the ingot, thereby forming a peeling layer at a depth position corresponding to a thickness of the wafer from the surface. A laser scanning irradiating the laser beam is performed for a plurality of times changing the irradiation position in a second direction while causing an irradiation position of the laser beam to move in a first direction. With a single laser scanning, a plurality of laser beams are irradiated in which irradiation positions are different in the first direction and the second direction.

公开(公告)号：US20240371629A1

公开(公告)日：2024-11-07

申请号：US18771239

申请日：2024-07-12

Applicant: DENSO CORPORATION

Inventor： Naoki MARUNO ,  Kazufumi AOKI ,  Bahman SOLTANI ,  Ryuta FURUKAWA

IPC: H01L21/02 ,  C25D11/02 ,  C25D11/32

Abstract: A surface processing method of a semiconductor wafer includes the following processes, procedures or steps: a pulsed current of which the current density is larger than or equal to 20 mA/cm2 is caused to flow through the semiconductor wafer as an anode in an electrolyte solution, thereby anodizing an object surface of the semiconductor wafer; and in a state where a surface processing pad having a grinding stone layer is disposed such that the grinding stone layer faces the object surface, an oxide generated by the anodization is selectively removed by the grinding stone layer.

公开(公告)号：US20240326174A1

公开(公告)日：2024-10-03

申请号：US18735769

申请日：2024-06-06

Applicant: DENSO CORPORATION

Inventor： Koichiro YASUDA ,  Ryota TAKAGI ,  Tomoki KAWAZU ,  Sodai NOMURA ,  Hideaki SHIRAI ,  Bahman SOLTANI ,  Shunsuke SOBAJIMA

IPC: B23K26/53 ,  B23K26/082 ,  B23K26/70 ,  B23K101/40 ,  H01L21/67

CPC classification number: B23K26/53 ,  B23K26/082 ,  B23K26/707 ,  H01L21/67092 ,  B23K2101/40

Abstract: A wafer manufacturing method for obtaining a wafer from an ingot includes the following procedure, steps or processes. A surface of one end side of the ingot in a height direction thereof is irradiated with a laser beam to which the ingot has transparency, thereby forming a peeling layer at a depth position corresponding to a thickness of the wafer from the surface. At this moment, the laser beam is irradiated such that a frequency of irradiation in a facet region is higher than that in a non-facet region. A wafer precursor as a portion between the surface of the ingot and the peeling layer is peeled from the ingot at the peeling layer. A major surface of a peeling body having a plate like shape, the peeling body being obtained by the wafer peeling step, is planarized electrically, chemically and mechanically, thereby obtaining a wafer.

公开(公告)号：US20230073379A1

公开(公告)日：2023-03-09

申请号：US17900950

申请日：2022-09-01

Applicant: DENSO CORPORATION

Inventor： Sodai NOMURA ,  Tomoki KAWAZU ,  Bahman SOLTANI ,  Yutaro ISSHIKI ,  Nobuyuki NUNOME ,  Shiro OKITA ,  Riku ONISHI

IPC: B28D5/00 ,  B23K26/53

Abstract: A manufacturing method of semiconductor wafers includes preparing a ingot having a first major surface and a second major surface in a back side of the first major surface, a peeling layer being formed in the ingot along the first major surface; and applying a load to the ingot from outside thereof with respect to a surface direction along the first major surface such that a moment with a supporting point which is a first end of the ingot in the surface direction acts on the ingot, thereby peeling a wafer precursor from the ingot. Also, a dynamic force may be applied to the ingot such that a tensile stress along an ingot thickness direction acts on an entire area of the ingot in the surface direction, thereby peeling the wafer precursor from the ingot.

公开(公告)号：US20220384185A1

公开(公告)日：2022-12-01

申请号：US17750450

申请日：2022-05-23

Applicant: DENSO CORPORATION

Inventor： Kazufumi AOKI ,  Naoki MARUNO ,  Bahman SOLTANI ,  Yuya KATO ,  Kyohei KOTAKE ,  Shinji MUKOTA ,  Manabu TOMISAKA ,  Yasuo ISHIHARA ,  Shusaku NAKAZAWA ,  Tetsuji YAMAGUCHI

IPC: H01L21/02 ,  H01L21/304

Abstract: Provided is a surface processing apparatus and a surface processing method for a SiC substrate using anodization. The surface processing apparatus for the SiC substrate includes a surface processing pad and a power supply device. The surface processing pad includes a grinding wheel layer. The grinding wheel layer is disposed facing a workpiece surface of the SiC substrate. The power supply device passes a pulsed current having a period greater than 0.01 seconds and less than or equal to 20 seconds for anodizing the workpiece surface to be processed by the grinding wheel layer through the SiC substrate as an anode in the presence of an electrolyte.

公开(公告)号：US20210301420A1

公开(公告)日：2021-09-30

申请号：US17211962

申请日：2021-03-25

Applicant: DENSO CORPORATION

Inventor： Bahman SOLTANI ,  Kazutoshi SASAYAMA ,  Yasushi HIBI

IPC: C30B29/36 ,  C30B33/02

Abstract: Provided is a production method of a SiC wafer which can increase the yield of a SiC wafer which can be prepared from a produced SiC single crystal ingot and the product yield of a semiconductor chip.
In forming cylindrical column parts from a SiC single crystal ingot, the diameters of the cylindrical column parts are gradually changed. Specifically, the SiC single crystal ingot configured to have a frustoconical shape is made into, instead of cylindrical column parts all having identical diameters, cylindrical column parts whose diameters increase from the upper surface toward the lower surface of the SiC single crystal ingot.

公开(公告)号：US20230115673A1

公开(公告)日：2023-04-13

申请号：US17960847

申请日：2022-10-06

Applicant: DENSO CORPORATION ,  National University Corporation Saitama University

Inventor： Bahman SOLTANI ,  Koichiro YASUDA ,  Ryota TAKAGI ,  Tomoki KAWAZU ,  Shunsuke SOBAJIMA ,  Yutaro ISSHIKI ,  Sodai NOMURA ,  Hideaki SHIRAI ,  Yohei YAMADA ,  Junichi IKENO

IPC: B23K26/38 ,  B23K26/402

Abstract: A manufacturing method for wafers includes: radiating a laser beam to a planned cutoff surface where the ingot is to be cutoff; and forming, with the radiation of the laser beam, a plurality of reformed sections at the planned cutoff surface to extend a crack from the reformed section, thereby slicing wafers, wherein an energy density of the laser beam exceeds a reforming threshold. The energy density satisfies at least one of conditions of a peak value of the energy density is lower than or equal to 44 J/cm2, a rising rate of the energy density at a portion corresponding to the most shallow position where the energy density reaches the reforming threshold Eth is larger than or equal to 1000 J/cm3, and a range of depth where the energy density exceeds the reforming threshold is smaller than or equal to 30 μm.