Changes in Crater Shape Caused by Low Angular Sputtered Flux during SIMS Argon Cluster Depth Profiling of Ultrathick Films
Shinichiro N. Muramoto, Cayla Collett
Argon cluster ions produce a low angular ejection of the sputtered flux, causing the crater bottom to shrink in size due to redeposition of the sputtered flux during depth profiling of ultrathick organic films. The progressing crater walls has two immediate effects for SIMS depth profiling: one is that the centering of the analysis beam inside the sputter crater will no longer ensure the best quality depth profile since the flat crater bottom is shifting towards either the fore- or aft-side of the crater depending on the film thickness; and two, the shrinking crater size enforces a maximum thickness of the film that could be depth profiled. For example, to leave a 100 µm crater bottom using a 500 µm sputter raster, the maximum depth achievable is 183 µm for a drug delivery film, 65 µm for a PMMA film, and 16 µm for a (PMMA/PAA)20 multilayer film. In addition, experiments on the multilayer film revealed that redeposition of the sputtered flux along the crater wall negatively affects depth resolution.
Journal of Vacuum Science and Technology A
tof-sims, argon cluster, gas cluster sources, gcib, thick films
and Collett, C.
Changes in Crater Shape Caused by Low Angular Sputtered Flux during SIMS Argon Cluster Depth Profiling of Ultrathick Films, Journal of Vacuum Science and Technology A
(Accessed February 21, 2024)