Positive Secondary Ion Yield Enhancement of Metal Elements Using Trichlorotrifluoroethane and Tetrachloroethene Backfilling
P Chi, John G. Gillen
Positive secondary ion yields are strongly enhanced by the presence of reactive gas species. Oxygen primary ion bombardment or oxygen backfilling is commonly used for this purpose. However, for some weak oxide forming metal elements such as Nb, Mo, and Ag, depth profiling with a primary oxygen beam or backfilling with oxygen may not enhance secondary ion yields. Recently, bombardment with an SF5+ primary ion beam demonstrated that fluorination of the sample surface might provide some level of signal enhancement (1-2). However, ion sources capable of generating SF5+ primary ion beams are not widely available. Another simple and inexpensive approach to enhance yields of the metal elements in secondary ion mass spectrometry (SIMS) is to backfill the sample chamber with a reactive gas such as chlorodifluoromethane (Freon-TF) or tetrachloroethene (C2Cl4). In this paper, we measured secondary ion yields obtained under ar+ bombardment with and without oxygen, Freon, and tetrachloroethene gas backfilling.
Applied Surface Science
backfilling, fluorination, metal elements, secondary IM yield enhancement, secondary ion mass spectrometry, SF<sub>5</sub><sup>+</sup>
and Gillen, J.
Positive Secondary Ion Yield Enhancement of Metal Elements Using Trichlorotrifluoroethane and Tetrachloroethene Backfilling, Applied Surface Science
(Accessed June 3, 2023)