Sputtering of aluminium alloys by bombardment with 0.5 keV neon ions

Film cathode structures find ever growing application in gas discharge devices. One of the main requirements for them is high sputtering stability. The authors suggest ways of producing cathode structures stable to ion bombardment. It is well known that the process of disastrous destruction of aluminium alloys starts on after 400 hours of irradiation with 0.5 keV neon ions at 3*1016 cm-2s-1 particle flow density and 400 Pa pressure in a gas discharge device while at lower flow densities and higher pressures the above effect is not observed. To improve the sputtering stability of materials they were modified with lithium and beryllium. The resistance to sputtering is assumed to be enhanced due to specific structure of the aluminium-lithium and aluminium-beryllium compounds and the specified texture of the bombarded surface through the adjustment of the angular distribution of the sputtered atoms. Modification was carried out by sputtering Be-Al-Li and Be-Al-Cu alloys (Al as a base, Be under 5%, Li and Cu under 2%) on the substrate with an Al-layer followed by heat treatment and ion bombardment. Heat treatment was undertaken in vacuum with the aim to stabilize the structure at 670-720 K. Ion bombardment was carried out to clean the surface with 0.5-1 keV neon ions prior to irradiation with 1 keV oxygen ions for producing an oxide film