METHOD OF USING PHASE PLATE IN TRANSMISSION ELECTRON MICROSCOPE

摘要

PROBLEM TO BE SOLVED: To provide a method of using a phase plate including a thin film in a transmission electron microscope (100).SOLUTION: The method comprises: introducing the phase plate in the transmission electron microscope; preparing the phase plate by irradiating the thin film with a focused electron beam; introducing a sample in the transmission electron microscope; and generating an image of the sample by using the prepared phase plate. The step of preparing the phase plate involves locally building up a vacuum potential resulting from a change in the electronic structure of the thin film by irradiating the phase plate with the focused electron beam. The vacuum potential leads to an absolute phase shift |φ| with a smaller value than at the non-irradiated thin film. Preferably the phase plate is heated to avoid contamination. The phase shift achieved with the phase plate can be tuned by varying the diameter of the irradiated spot.