Depth Resolution, Angle Dependence, and the Sputtering Yield of Irganox 1010 by Coronene Primary Ions
文摘
A study is reported of the depth resolution and angle dependence of sputtering yields using the reference organic material, Irganox 1010, for a new coronenep>+p> depth profiling ion source at 8 and 16 keV beam energies. This source provides excellent depth profiles as shown by 8.5 nm marker layers of Irganox 3114. Damage occurs but may be ignored for angles of incidence above 70掳 from the surface normal, as shown by X-ray photoelectron spectroscopy (XPS) of the C 1s peak structure. Above 70掳, XPS profiles of excellent depth resolution are obtained. The depth resolution, after removal of the thickness of the delta layers, shows a basic contribution of 5.7 nm together with a contribution of 0.043 times the depth sputtered. This is lower than generally reported for cluster sources. The coronenep>+p> source is thus found to be a useful and practical source for depth profiling organic materials. The angle dependencies of both the undamaged and damaged materials are described by a simple equation. The sputtering yields for the undamaged material are described by a universal equation and are consistent with those obtained for C60p>+p> sputtering. Comparison with the sputtering yields using an argon gas cluster ion source shows great similarities, but the yields for both the coronenep>+p> and C60p>+p> primary ion sources are slightly lower.