CATHODE SPUTTERING OF TUNGSTEN

The radioactive isotope method was used to investigate cathode sputtering of a polycrystalline tungsten target, the temperature of which was approximately 1800K. It is assumed that sputtering of a clean surface takes place at such a temperature. In order to prevent evaporation of the target, an instrument was constructed, which made it possible to measure simultaneously the amount m sub 1 of the material evaporated from one side of the target, and the amount m sub 2 of the material evaporated and sputtered during the same time from the opposite side. The amount of sputtered material was m = m sub 2 - m sub 1. The energy dependences of the coefficient W of sputtering of tungsten by ions Cs(+), Rb(+), K(+), and Li(+) is obtained. In the energy region 300-2500 eV, these dependences are represented by straight lines. A correlation is established between the value of the coefficient of cathode sputtering and the energy received by the target from the incoming ion in two successive collisions with the lattice atoms. Katodnoe Raspylenie Volframa, unedited rough draft trans. of Akademiya Nauk Uzbekskoi SSR, Tashkent. Doklady, n10 p22-6 1964.