| AVS 58th Annual International Symposium and Exhibition | |
| Applied Surface Science Division | Tuesday Sessions |
| Session AS-TuM |
| Session: | Imaging and 3D Chemical Analysis |
| Presenter: | Derk Rading, ION-TOF GmbH, Germany |
| Authors: | D. Rading, ION-TOF GmbH, Germany N. Havercroft, ION-TOF USA, Inc. R. Moellers, ION-TOF GmbH, Germany E. Niehuis, ION-TOF GmbH, Germany |
| Correspondent: | Click to Email |
Preservation of molecular information under high-dose sputtering conditions has become increasingly important. It is not only a pre-requisite for depth profiling and 3D analysis of organic materials, but also extends the survival of sample material beyond the static SIMS limit in high lateral resolution imaging. In this respect, the use of a high energy cluster ion beam for sputtering such as SF5 [1] and C60 [2-4] has aroused considerable interest. With the beam energies typically applied, the total energy is high enough for reasonable sputter rates whereas the energy per atom, of about several 100 eV, is considered low enough to minimize sample damage. However, it has been demonstrated that a variety of organic compounds cannot be profiled in a satisfactory way and characteristic molecular secondary ion signals are lost [5-7]. In this respect it has been shown recently that massive argon cluster ions can be successfully applied as primary projectiles in SIMS [8,9].
We equipped a TOF.SIMS 5 instrument with a Bin, C60 and an Arn cluster ion source in order to compare the possibilities and limitations of these projectiles for depth profiling of polymer materials. In this contribution, we will focus on dual beam depth profiling where the analysis is done with Bin and the sputtering with C60 and Arn cluster ion beams, respectively. Stability and intensity of characteristic high mass molecular ion signals as well as sputter yields and depth resolution will be compared. For this purpose different beam energies resulting in 2 - 10 eV/atom for Arn and 167 - 667 eV/atom for C60 sputtering have been applied to various polymer samples. From our experiments we can conclude that most of the limitations C60 sputtering suffers from could be successfully overcome and that the Ar GCIB seems to be a more universal tool for sputtering of organic materials.
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