There are many challenges in accomplishing tip-enhanced Raman spectroscopy (TERS) and obtaining a proper tip is probably the greatest one. Since tip size, composition, and geometry are the ultimate parameters that determine enhancement of intensity and lateral resolution, the tip becomes the most critical component in a TERS experiment. However, since the discovery of TERS the cantilevers used in atomic force microscopy (AFM) have remained basically the same: commercial silicon (or silicon nitride) tips covered by a metallic coating. The main issues of using metal-coated silicon cantilevers, such as wearing off of the metal layer or increased tip radius, can be completely overcome by using all-metal cantilevers. Until now in TERS experiments such probes have only been used in a scanning tunneling microscope or in a tuning fork-based shear force microscope but not in AFM. In this work for the first time, we show the use of compact silver cantilevers that are fully compatible with contact and tapping modes in AFM demonstrating their superb performance in TERS experiments.

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"Copper oxide atomic layer deposition on thermally pretreated multi-walled carbon nanotubes for interconnect applications", Microelectron. Eng. 107, 223-228 (2013 Carbon nanotubes (CNTs) are a highly promising material for future interconnects. It is expected that a decoration of the CNTs with Cu particles or also the filling of the interspaces between the CNTs with Cu can enhance the performance of CNT-based interconnects. The current work is therefore considered with thermal atomic layer deposition (ALD) of Cu x O from the liquid Cu(I) β-diketonate precursor [( n Bu 3 P) 2 Cu(acac)] and wet oxygen at 135°C. This paper focuses on different thermal in-situ pre-treatments of the CNTs with O 2 , H 2 O and wet O 2 at temperatures up to 300°C prior to the ALD process. Analyses by transmission electron microscopy show that in most cases the Cu x O forms particles on the multi-walled CNTs (MWCNTs). This behavior can be explained by the low affinity of Cu to form carbides. Nevertheless, also the formation of areas with rather layer-like growth was observed in case of an oxidation with wet O 2 at 300°C. This growth mode indicates the partial destruction of the MWCNT surface. However, the damages introduced into the MWCNTs during the pre-treatment are too low to be detected by Raman spectroscopy. Abstract:Carbon nanotubes (CNTs) are a highly promising material for future interconnects due to the remarkable properties they combine such as high thermal conductivity [1,2], ballistic transport over distances in the µm-range [3,4] and the ability to carry high current densities with low electro migration [5]. To make CNT-based interconnects competitive to the currently used copper technology, several challenges have to be overcome, such as formation of low-resistivity contacts, aligned growth both for vertical and horizontal interconnects with high density [6].

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