公开(公告)号：US20210225674A1

公开(公告)日：2021-07-22

申请号：US16646790

申请日：2019-02-08

Applicant: Hitachi High-Technologies Corporation

Inventor： Soichiro ETO ,  Hiroyuki MINEMURA ,  Tatehito USUI

IPC: H01L21/67 ,  H01J37/32 ,  H01L21/3065 ,  H01L21/66 ,  G01B11/06

Abstract: In thickness/depth measurement of a wafer in etching, variation occurs in detected light quantity due to fluctuation of light quantity of a light source or fluctuation of air in a region through which light passes, and measurement accuracy of thickness/depth is reduced, and thus the total light quantity or average light quantity of an arbitrary wavelength is calculated from an optical spectrum measured at each time instant during etching, estimated total light quantity or estimated average light quantity at the present time, which is estimated using total light quantity or average light quantity measured prior to the present time, is calculated, a change rate, as a ratio of the total light quantity at the present time to the estimated total light quantity or a ratio of the average light quantity to the estimated average light quantity, is calculated, the calculated change rate is used to correct light quantity of each wavelength at the present time, and the corrected light quantity of each wavelength is used to perform thickness/depth measurement.

公开(公告)号：US20200303152A1

公开(公告)日：2020-09-24

申请号：US16089281

申请日：2016-03-29

Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION

Inventor： Takashi OHSHIMA ,  Hiroyuki MINEMURA ,  Yumiko ANZAI ,  Momoyo ENYAMA ,  Yoichi OSE ,  Toshihide AGEMURA

IPC: H01J37/073 ,  H01J37/22

Abstract: To provide an electron microscope capable of performing the switching-over between normal illumination and annular illumination, wide-area irradiation, an interference pattern as desired or normal illumination in an expeditious and readily manner or achieving a better S/N ratio, the electron microscope comprises a photocathode 101 with negative electron affinity in use; an excitation optical system to excite the photocathode; and an electron optics system to irradiate an electron beam 13 generated from the photocathode by excitation light 12 irradiated through the excitation optical system onto a sample, the excitation optical system including a light source device 107 for the excitation light; and an optical modulation means 108 which is disposed in an optical path of the excitation light to perform spatial phase modulation to the excitation light.