Development of an Ultra High Resolution Scanning Electron Microscope by Means of a Field Emission Source and In-Lens System

An ultra high resolution scanning electron microscope, which is composed of a cold cathode field emission gun and an in-lens system for specimens, has been developed. Probe size is estimated 0.8nm at 30kV by calculation and confirmed experimentally using high atomic number samples such as fine Pt particles sputter-coated on carbon. Three stage ion pumps for the column and a turbo molecular pump for the specimen chamber have been used for a totally dry vacuum system. Applications for fine metal oxide particles and biological samples observed directly without any metal coating, and applications chosen especially to show lower voltage performance, are shown