Low energy electron beam source for etching of materials used in microelectronics

We have generated beams with electron current densities of more than 10 m A/cm2 at energies between 150 and 900 eV using a plasma source. This electron source can be operated at background pressures between 0.01 and 0.1 Torr in helium and with the addition of various gases, producing electron beams up to 3.8 cm in diameter. The broad-area beam can be used to induce gas-phase and surface reactions and has been successfully used to achieve anisotropic etching of SiO2 and Si films in reactant gases CF4 and SF6. (Author). 14 refs, 10 figs