Patent ID: 11915901
Assignee: ULVAC-PHI, INCORPORATED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. A surface imaging apparatus based on detection of secondary electrons or secondary ions, comprising:
a spatially scanned and pulsed primary excitation source resulting in secondary electrons or secondary ions which are detected and provide the modulated signal for imaging of the sample;
a source of a pulsed positive ion flood neutralizer beam;
a source of a pulsed electron flood neutralizer beam; and
independent columns for the positive ion flood neutralizer beam and the electron flood neutralizer beam,
wherein the source of a pulsed positive ion flood neutralizer beam and the source of an electron flood neutralizer beam are independently controllable and provide dual polarity flood beams to effect neutralization of surface charge and surface potential variation, wherein the pulsed charge neutralizing flood beams are interleaved with the pulsed primary excitation source, and
wherein the dual polarity flood beams comprise an electron beam and a positively charged ion beam.