Photoemission Electron Microscope for Non-Destructive Oxide Layer Observation

The patent replaces the mechanical destruction method (cutting or removing the upper electrode) with a photoemission electron microscope observation method that uses light to emit electrons from the sample surface. This allows non-destructive observation of the oxide layer by detecting photoelectrons emitted when laser light irradiates the sample, eliminating the need for physical sample preparation that causes damage.

The patent introduces photoelectrons as an intermediary carrier to transfer information from the oxide layer to the detector. By using photoelectrons emitted from the oxide layer surface as a mediator, the observation can be performed without direct mechanical contact or destruction of the sample structure, enabling non-destructive imaging of the oxide layer and filament.

The patent substitutes mechanical removal of the upper electrode with optical irradiation using laser light. The laser light penetrates or interacts with the upper electrode and oxide layer to generate photoelectrons, allowing observation of the oxide layer through electron emission without physically removing any components, thus preserving sample integrity while maintaining accessibility for observation.

The patent changes the observation parameter from physical access (requiring electrode removal) to optical/electronic detection (using photoemission). By changing the detection method from mechanical to optical-electronic, the oxide layer becomes accessible for observation through photoelectron emission while the sample structure remains intact and preserved.