Heng Qiyao Li

US Patent:

20210319977, Oct 14, 2021

Filed:

Apr 8, 2021

Appl. No.:

17/226017

Inventors:

- Veldhoven, NL
Weimin ZHOU - San Jose CA, US
Xiaoxue CHEN - Fremont CA, US
Xiaoyu JI - Beijing, CN
Heng LI - San Jose CA, US
Shahedul HOQUE - Milpitas CA, US
Zongyao LI - San Jose CA, US
Shuhao LIU - San Jose CA, US
Weiming REN - San Jose CA, US

International Classification:

H01J 37/28
H01J 37/145
H01J 37/244
H01J 37/147

Abstract:

Systems and methods of imaging a sample using a charged-particle beam apparatus are disclosed. The charged-particle beam apparatus may include a compound objective lens comprising a magnetic lens and an electrostatic lens, the magnetic lens comprising a cavity, and an electron detector located immediately upstream from a polepiece of the magnetic lens and inside the cavity of the magnetic lens. In some embodiments, deflectors may be located between the electron detector and the opening of the polepiece adjacent to the sample to achieve a large field of view. Electron distributions among the detectors can be manipulated without changing the landing energy by changing the potential of the control electrode(s) in the electrostatic objective lens. The electron source can be operated with several discrete potentials to cover different landing energies, while the potential difference between electron source and the extractor is fixed.