公开(公告)号：US11276554B2

公开(公告)日：2022-03-15

申请号：US16941806

申请日：2020-07-29

Applicant: Hitachi High-Tech Corporation

Inventor： Takeyoshi Ohashi ,  Yusuke Abe ,  Kenji Tanimoto ,  Kaori Bizen ,  Hyejin Kim

IPC: H01J37/28 ,  H01J37/244 ,  H01J37/12

Abstract: A scanning electron microscope includes an electron-optical system including an electron source and an objective lens, a stage on which a sample is placed, a secondary electron detector disposed adjacent to the electron source relative to the objective lens and configured to detect secondary electrons, a backscattered electron detector disposed between the objective lens and the stage and configured to detect backscattered electrons, a backscattered electron detection system controller configured to apply a voltage to the backscattered electron detector, and a device-control computer configured to detect a state of an electrical charge carried by the backscattered electron detector based on signal intensity at the secondary electron detector when the primary electrons are applied to the sample with a predetermined voltage applied to the backscattered electron detector.

公开(公告)号：US20210384006A1

公开(公告)日：2021-12-09

申请号：US17338353

申请日：2021-06-03

Applicant: Hitachi High-Tech Corporation

Inventor： Takeyoshi Ohashi ,  Hyejin Kim ,  Yusuke Abe ,  Kenji Tanimoto

IPC: H01J37/21 ,  G06T1/00 ,  G06T7/73 ,  H01J37/22 ,  H01J37/145

Abstract: When focus adjustment is performed according to the height of the surface of a sample at each inspection point in order to continuously inspect a plurality of inspection points on a wafer by using an electron microscope, even when the focus adjustment by an electrostatic lens in which a variation of heights of inspection points is greater than a predetermined range, and that can perform adjustment at a high speed and adjustment by an electromagnetic lens with a low speed are required to be used together, a flow of focus adjustment in which the number of times of the adjustment by the electromagnetic lens is reduced by using a relation of changes of heights at inspection points, an inspection order, and a range in which an electrostatic focus can be performed is realized, so that inspection with high throughput is made possible.

公开(公告)号：US11670479B2

公开(公告)日：2023-06-06

申请号：US17338353

申请日：2021-06-03

Applicant: Hitachi High-Tech Corporation

Inventor： Takeyoshi Ohashi ,  Hyejin Kim ,  Yusuke Abe ,  Kenji Tanimoto

IPC: H01J37/28 ,  H01J37/21 ,  G06T1/00 ,  G06T7/73 ,  H01J37/145 ,  H01J37/22

CPC classification number: H01J37/21 ,  G06T1/0007 ,  G06T7/73 ,  H01J37/145 ,  H01J37/222 ,  G06T2200/24 ,  G06T2207/10056 ,  G06T2207/30148

Abstract: When focus adjustment is performed according to the height of the surface of a sample at each inspection point in order to continuously inspect a plurality of inspection points on a wafer by using an electron microscope, even when the focus adjustment by an electrostatic lens in which a variation of heights of inspection points is greater than a predetermined range, and that can perform adjustment at a high speed and adjustment by an electromagnetic lens with a low speed are required to be used together, a flow of focus adjustment in which the number of times of the adjustment by the electromagnetic lens is reduced by using a relation of changes of heights at inspection points, an inspection order, and a range in which an electrostatic focus can be performed is realized, so that inspection with high throughput is made possible.

公开(公告)号：US20210043420A1

公开(公告)日：2021-02-11

申请号：US16941806

申请日：2020-07-29

Applicant: Hitachi High-Tech Corporation

Inventor： Takeyoshi Ohashi ,  Yusuke Abe ,  Kenji Tanimoto ,  Kaori Bizen ,  Hyejin Kim

IPC: H01J37/28 ,  H01J37/244 ,  H01J37/12

Abstract: A scanning electron microscope includes an electron-optical system including an electron source and an objective lens, a stage on which a sample is placed, a secondary electron detector disposed adjacent to the electron source relative to the objective lens and configured to detect secondary electrons, a backscattered electron detector disposed between the objective lens and the stage and configured to detect backscattered electrons, a backscattered electron detection system controller configured to apply a voltage to the backscattered electron detector, and a device-control computer configured to detect a state of an electrical charge carried by the backscattered electron detector based on signal intensity at the secondary electron detector when the primary electrons are applied to the sample with a predetermined voltage applied to the backscattered electron detector.