USE OF CATHODE LENS IN SCANNING ELECTRON-MICROSCOPE FOR LOW-VOLTAGE APPLICATIONS

At a landing energy of 10 eV it is Possible to achieve spatial resolut ion of the same order as at the nominal energy, which is usually 15 ke V in the classical scanning electron microscope, by taking advantages of the optical properties of the cathode lens. Two different types of the detection system were designed and tested to learn as much about t he optical properties of this system as possible and to start to under stand the contrast mechanisms at very low energies. Great changes in t he contrast take place when the landing energy is changed from 10 eV t o an energy of about 2 keV.