公开(公告)号：US20210143070A1

公开(公告)日：2021-05-13

申请号：US17151821

申请日：2021-01-19

Applicant: DENSO CORPORATION

Inventor： Shinya TAKEI ,  Shuhei MITANI ,  Haruhito ICHIKAWA ,  Ippei TAKAHASHI ,  Yukihiro WAKASUGI

IPC: H01L21/66 ,  H01L21/02

Abstract: A semiconductor wafer includes a silicon carbide wafer and an epitaxial layer, which is disposed at a surface of the silicon carbide wafer and made of silicon carbide. The semiconductor wafer satisfies a condition that a waviness value is equal to or smaller than 1 micrometer. The waviness value is a sum of an absolute value of a value α and an absolute value of a value β. A highest height among respective heights of a plurality of points with reference to a surface reference plane within a light exposure area is denoted as the value α. A lowest height among the respective heights of the points at the epitaxial layer with reference to the surface reference plane within the light exposure area is denoted as the value β.

公开(公告)号：US20220260713A1

公开(公告)日：2022-08-18

申请号：US17723681

申请日：2022-04-19

Applicant: DENSO CORPORATION

Inventor： Tomoki TANEMURA ,  Nobuaki MATSUDAIRA ,  Ippei TAKAHASHI

IPC: G01S15/931 ,  G05D1/02 ,  G01S15/46

Abstract: An obstacle detection apparatus that detects an obstacle existing around a vehicle is provided to include an ultrasonic sensor and a controller. The ultrasonic sensor is provided in the vehicle at a position having a predetermined height from a road surface. The ultrasonic sensor includes a plurality of ultrasonic elements configured to transmit an exploration wave toward outside of the vehicle, and receive a reflected wave reflected by an obstacle as a reception wave. The controller is configured to derive (i) an obstacle distance and (ii) an obstacle height based on an intensity of the reception wave received by each of the plurality of ultrasonic elements and a phase difference in the reception wave received by each of the plurality of ultrasonic elements.