Volume 44, Issue 10

The characterization of nanoscale regions in present and future device structures of leading-edge microelectronic products requires probes with dedicated features tailored on the nanoscale. SPM tips are used not only for conventional AFM characterization, but also for electrical, thermal and optical investigation of devices. For particular applications as nano-Raman spectroscopy or conductive AFM, highly reproducible metal tips or metallized tips are needed. In this paper, new approaches to tailor those tips using the FIB technique, and to characterize the tips using dedicated structures and adapted AFM methods are described. Based on a numerical procedure, the tip quality is described quantitatively. The described preparation and calibration techniques offer new possibilities for the routine application of nanostructures and nanodevices as needed for advanced SPM techniques and nanosensors.

Electrical contact materials are expected to combine improved mechanical and physical properties with good corrosion resistance at increased temperatures. One of the most widely used groups of contact materials are internally oxidized dispersion hardened silver alloys. The principle of their production involves selective oxidation of less noble solute elements (usually Mg, Al, Sn, Cd and Zn) forming the fine dispersion of oxide particles in the solvent silver matrix. In this study the internal oxidation of dilute silver alloy containing 2 at. % of tin was extensively investigated. The morphological evolution of the alloy and the internal oxidation kinetics were determined by several metallographic examinations and in-situ electrical resistance measurements in the air atmosphere and in the temperature range from 600°C to 800°C. The results of experiments and their analyses show that the microstructural changes during internal oxidation of Ag-Sn alloy are strongly dependent on the annealing temperature. At the highest temperatures the perfectly dispersive distribution of the oxide particles SnO2 in the silver matrix was found, while at lower temperatures the formation of inner oxide bands and distribution of oxide particles along the grain boundaries is predominate.