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. (2012). Angle-resolved environmental X-ray photoelectron spectroscopy: A new laboratory setup for photoemission studies at pressures up to 0.4 Torr. Review of Scientific Instruments, 83(9) The paper presents the development and demonstrates the capabilities of a new laboratory-based environmental X-ray photoelectron spectroscopy system incorporating an electrostatic lens and able to acquire spectra up to 0.4 Torr. The incorporation of a two-dimensional detector provides imaging capabilities and allows the acquisition of angle-resolved data in parallel mode over an angular range of 14° without tilting the sample. The sensitivity and energy resolution of the spectrometer have been investigated by analyzing a standard Ag foil both under high vacuum (10 −8 Torr) conditions and at elevated pressures of N 2 (0.4 Torr). The possibility of acquiring angle-resolved data at different pressures has been demonstrated by analyzing a silicon/silicon dioxide (Si/SiO 2 ) sample. The collected angle-resolved spectra could be effectively used for the determination of the thickness of the native silicon oxide layer. The paper presents the development and demonstrates the capabilities of a new laboratory-based environmental X-ray photoelectron spectroscopy system incorporating an electrostatic lens and able to acquire spectra up to 0.4 Torr. The incorporation of a two-dimensional detector provides imaging capabilities and allows the acquisition of angle-resolved data in parallel mode over an angular range of 14 • without tilting the sample. The sensitivity and energy resolution of the spectrometer have been investigated by analyzing a standard Ag foil both under high vacuum (10 −8 Torr) conditions and at elevated pressures of N 2 (0.4 Torr). The possibility of acquiring angle-resolved data at different pressures has been demonstrated by analyzing a silicon/silicon dioxide (Si/SiO 2 ) sample. The collected angle-resolved spectra could be effectively used for the determination of the thickness of the native silicon oxide layer. Disciplines Mechanical Engineering

Keywords: platinum silicide, thin films, X-ray photoelectron spectroscopy, nanoindentation, conductive atomic force microscopy Controlling the stoichiometry and properties of thin films formed from solid-state reactions is relatively unexplored, yet important for a broad range applications including many throughout the semiconductor industry. [1,2] Here we use source-limited solid-state diffusion to tune the stoichiometry and properties of thin films of platinum silicide (Pt x Si), a material with multiple attractive properties for electro-mechanical applications. [3,4] We demonstrate for the first time the formation of Pt x Si from thin sequentially-deposited layers of platinum (Pt) and amorphous silicon (a-Si), and show that the resulting stoichiometry can be tuned over a wide range by simply changing the thickness ratio of the precursor films. Pt-rich silicide films are especially attractive as a contact material for nanoelectromechanical (NEM) contact switches, due to the combination of high hardness and elastic modulus, surface stability, and metal-like electrical conductivity. This method of tuning the stoichiometry and properties of thin films is applicable to any metal silicide. 2Metal silicides possess a rare combination of thermal stability, mechanical robustness, and metal-like electrical conductivity. This renders them popular in both bulk and thin film form for many structural and electronic applications, such as materials for jet engines, thermoelectric devices, Ohmic and rectifying contacts to silicon, local interconnects, and diffusion barriers. [5] A more recent application involves their use in NEM contact switches.NEM switches are a potential next-generation, low power alternative to fully-electronic complementary metal-oxide semiconductor (CMOS) transistors (Figure 1a) that may significantly decrease microprocessor power consumption. [1,2,6] These devices promise orders of magnitude lower power consumption and superior ON/OFF ratios than CMOS (Figure 1b) Ð a consequence of NEM device topology and the presence of a physical gap between the source and drain terminals. [1,2] NEM switches have also demonstrated applications not accessible with CMOS Ð most notably exposure to high temperature, [7] radiation, [8,9] and external electric fields.[10] These advantages also render them of interest for future memory technologies.[1] However, the reliability of the contact interface is a concern due to tribological issues, and remains a key challenge for their commercialization. a, Schematic of a typical solid-state switch and an electrostatically actuated mechanical switch that highlights the structural analogies between both switch types. The magnified view to the right illustrates the physical separation between source and drain in the mechanical switch in its OFF state and emphasizes the demanding requirements on contact materials in nanoscale mechanical switches, which are a consequence of the harsh operating conditions (high contact stresses and current densities). b, Schematic current-voltage p...

The nanoscale geometry of probe tips used for atomic force microscopy (AFM) measurements determines the lateral resolution, contributes to the strength of the tip-surface interaction, and can be a significant source of uncertainty in the quantitative analysis of results. While inverse imaging of the probe tip has been used successfully to determine probe tip geometry, direct observation of the tip profile using electron microscopy (EM) confers several advantages: it provides direct (rather than indirect) imaging, requires fewer algorithmic parameters, and does not require bringing the tip into contact with a sample. In the past, EM-based observation of the probe tip has been achieved using ad hoc mounting methods that are constrained by low throughput, the risk of contamination, and repeatability issues. We report on a probe fixture designed for use in a commercial transmission electron microscope that enables repeatable mounting of multiple AFM probes as well as a reference grid for beam alignment. This communication describes the design, fabrication, and advantages of this probe fixture, including full technical drawings for machining. Further, best practices are discussed for repeatable, non-destructive probe imaging. Finally, examples of the fixture's use are described, including characterization of common commercial AFM probes in their out-of-the-box condition.