Abstract: A scanning photoelectron microscope comprises a stage on which a sample is placed in a state in which gas around the sample is present, a light source emitting light of a wavelength capable of causing photoelectrons to be emitted from the sample, an optical system for condensing the light from the light source on the sample, scanning means for scanning the sample and the light relative to each other, and detecting means capable of applying positive potential to the sample, and detecting the photoelectrons created from the sample by the condensing, through the gas.

Abstract: A scanning photoelectron microscope comprises a stage on which a sample is placed in a state in which gas around the sample is present, a light source emitting light of a wavelength capable of causing photoelectrons to be emitted from the sample, an optical system for condensing the light from the light source on the sample, scanning means for scanning the sample and the light relative to each other, and detecting means capable of applying positive potential to the sample, and detecting the photoelectrons created from the sample by the condensing, through the gas.

Abstract: A scan type electron microscope has an electron beam generating source for generating an electron beam with which a sample is irradiated; a sample chamber, supplied with a gas for effecting a gas amplification, for housing the sample; a secondary electron detecting means, installed in the sample chamber, for detecting secondary electrons gas-amplified by the gas after being generated from the sample with the irradiation of the electron beam; and an electrode, disposed between the sample and the secondary electron detecting means, for absorbing positive ions produced when the secondary electrons are gasamplified by the gas. The electrode may be constituted by a further fine tube extended from a pressure limiting aperture to a position just above the sample and formed with a path of the electron beam. The absorption of the positive ions prevents a positive charge-up of the sample, whereby a voltage between the sample and the secondary electron detecting means can be kept at a fixed level.