Patent · US Expired

Electron beam exposure or system inspection of measurement apparatus and its method and height detection apparatus

US6333510A · kind A · utility

25Cited by
3References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 21, 2000
Grant dateDec 25, 2001
Priority date
Expiry dateAug 21, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J2237/3175
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electron beam apparatus and method for at least obtaining an image of a specimen. The apparatus includes an electron optical system having an electron beam source, an element for deflecting electron beams emitted from the electron beam source, an objective lens for converting and irradiating electron beams deflected by the deflection element onto the specimen and a detector for detecting a secondary electron emanated from the specimen by irradiation of the electron beams. The apparatus further includes a projection optical system for projecting a light pattern onto a surface of the specimen in the vicinity of a beam axis of the electron optical system from an oblique direction to the surface, a detection optical system for detecting an image of the light pattern projected on the surface of the specimen and outputting information of a position of the image of the light pattern, and a surface height detection unit for outputting height information of the surface of the specimen by using the output information from the detection optical system. A focus controller is provided for focusing the electron beam onto the surface of the specimen by controlling the objective lens of the ele…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.