Study on magnetic focusing and deflection electron microbeam probe systems

A compact low voltage electron microbeam probe system with magnetic focusing and deflection is proposed which has a fine field emission tip aligned by the STM method. An apertured magnetic screen is used to make the magnetic field vanish at the tip surface. The compact combined magneto-electrostatic lens and deflection system has very small aberrations and extreme fine spot sizes of nanometer order can be produced over scanning fields of 7.5 × 7.5−10 × 10 μm2 for a beam half-angle on the image side of 40–50 mrad without dynamic correction of the deflection aberration.