Abstract :
Today, thermionically derived electron streams and beams are applied across a spectrum ranging from the electron beam etching of semiconductor masks to the melting of metals in bulk, with the beam currents involved ranging from 1 nano amp to amperes. The spectrum of application includes domestic CR tubes, thermionic valves, X-ray generators, electron microscopes and electron beam welding and machining equipment. The author discusses the equipment used to produce electron beams and its operation
