Observation apparatus and optical axis adjustment method

Abstract

Ordinary charged particle beam apparatuses have each been an apparatus manufactured for dedicated use in making observations in a gas atmosphere at atmospheric pressure or at a pressure substantially equal thereto. There have existed no devices capable of simply making observations using an ordinary high-vacuum charged particle microscope in a gas atmosphere at atmospheric pressure or at a pressure approximately equal thereto. Furthermore, ordinary techniques have been incapable of observing the same spot of the sample in such an atmosphere using a charged particle beam and light simultaneously. This invention thus provides an apparatus including: a charged particle optical tube that irradiates a sample with a primary charged particle beam; a vacuum pump that evacuates the inside of the charged particle optical tube; a diaphragm arranged to separate a space in which the sample is placed from the charged particle optical tube, the diaphragm being detachable and allowing the primary charged particle beam to permeate or pass therethrough; and an optical microscope positioned on the opposite side of the charged particle optical tube across the diaphragm and the sample, the optical microscope having an optical axis thereof aligned with at least part of an extension of the optical axis of the charged particle optical tube.