AVS2010 Session EW-TuL: Exhibitors & Manufacturers Technology Spotlight

Surface treatment of polymers produces materials that exhibit a wide range of surface compositions, properties and structures. The chemical and structural properties of these novel materials can be exploited for the fabrication of devices for bio-medical and electronics applications. The combination of a variety of complementary surface-sensitive electron spectroscopies maximizes the information available to the analyst for full quantitative surface characterization of standard and patterned polymer surfaces

This presentation will show how the new Thermo Scientific ESCALAB 250Xi, a multi-technique surface analysis system, can be used to investigate the chemistry and structure of various standard and patterned polymer samples. Chemical changes produced by surface treatments were examined by high energy resolution XPS and angle resolved XPS. Complementary REELS measurements were used to examine the level of carbon unsaturation at the uppermost surface of each of the polymer samples. Ultraviolet Photoelectron Spectroscopy (UPS), REELS and XPS valence band analysis were used together to comprehensively evaluate the valence electronic structure of the polymers.

C₆₀ and coronene cluster ion sources have been recently introduced for XPS and TOF-SIMS sputter depth profiling of many polymer materials. These sources have also been very successful for the removal of common organic contamination before XPS and TOF-SIMS surface analysis. This experience with C₆₀ and coronene cluster ion sources has revealed several polymer systems for which these cluster sources can not produce “non-destructive” chemical depth profiling with XPS and TOF-SIMS. Typically these polymers are either cross-linked, highly susceptible to radiation induced cross-linking, or are polymerized with bonds that are not amenable to sputter depth profiling. A new gas cluster ion beam (GCIB) source that produces massive argon cluster ions will be shown to successfully produce XPS and TOF-SIMS depth profiles on challenging materials such as polyimide thin films. The GCIB source can also be used to remove ion beam and plasma induced damaged layers on polymer materials.

This new ion source will greatly expand the breadth of materials for which XPS can produce chemical state depth profiles on multi-layer thin films. In addition, the use of a dual beam depth profiling approach with GCIB and LMIG sources on TOF-SIMS instruments will expand the applications for 3D characterization of polymer and biomaterial samples. Examples will be presented demonstrating the benefits of the GCIB for both XPS and TOF-SIMS analyses.

New developments in the use of Polycyclic Aromatic Hydrocarbons (PAH's) for the preparation and analysis of organic surfaces will be presented. These developments have resulted from an enhanced understanding of the processes involved and optimization of the sputtering conditions required to achieve optimal results. Once the spectral data has been obtained, improvements and the development of new software processing techniques have been employed to further enhance the information content and understanding of the sample composition. The application of these techniques to both organic and inorganic materials will be described.

Largely on account of technology miniaturization, nanomechanical testing (usually nanoindentation) has become a routine part of material and device development. Yet it is often found that the length scale of interest (individual nanopillars, nanoparticles, and nanowires, or even smaller) is below the comfort zone of conventional nanomechanical testers. An intriguing way of circumventing this problem is to combine electron microscopy with nanomechanical testing in an in-situ way. Hysitron, Inc., the world leader in nanomechanical test instruments, offers PI 95 TEM PicoIndenter™ and PI 85 SEM PicoIndenter™ products for quantitative nanomechanical testing in the transmission electron microscope (TEM) and the scanning electron microscope (SEM), respectively. The PI 85 platform is also suitable for operating in SEM systems combined with a focused ion beam (FIB). This presentation will provide a technology overview and application examples demonstrating the power of time correlating directly-observed morphology, topography, and microstructure evolution to the corresponding nanomechanical data. In addition, given the vacuum environment within electron microscopes, the prospect of utilizing the core of the technology in other vacuum applications will be discussed. Other than material compatibility issues, the main concern of vacuum is the nearly non-existent mechanical damping (and the correspondingly high mechanical quality factor) which must be properly dealt with to achieve the stability necessary for high performance.