Analyses of spreading resistance measurements in Si samples with dopant profiles of the dopant sequence lowly doped on highly doped yield unreliable results if the dopant profiles are extremely steep or ultra-shallow. Reasons for this behavior are seen in effects of penetration of the probe tips into the Si sample and in the presence of a zone of a metallically conducting Si phase beneath the probe tip. Atomic force microscopy has been used to investigate the geometry of probe tip indents and scanning electron microscopy to investigate the geometry of the probe tip itself. Results of loading-unloading experiments by means of nanoindentation with a conventional spreading resistance probe tip as indenter enable us to estimate the depth of the metallic Si phase zone. It ranges from about the fourfold up to the sevenfold of the residual depth after unloading the probe tip.

Surface potential difference (SPD) measurements have shown to be effective in in-line characterizing charging non-uniformity and non-visual residues for both process and tool development but also in in-line characterizing properties of ultra thin transistor work function layers

A technology has been developed for the extreme miniaturization of lithium ion micro batteries using wafer level processing. These batteries will be used as electronic buffer storage in future miniaturized sensor nodes, data loggers, RFID devices and medical applications. The micro batteries can store the energy generated by energy harvesters which are a prerequisite for energy autarkic wireless sensor nodes and enable the technology for ambient intelligence and the internet of things.Between 2000 and 10000 micro batteries can be fabricated on one 300 mm wafer, being a low cost process. Process optimization of silicon processing was necessary to define cavities for the electrochemical electrodes, current collectors and contacts. The active masses are applied by means of dispensing. Technology development was required to optimize the electrode pastes and electrolyte for application in micro channel structures. Thus a wide variety of state of the art electrode materials can be used and the battery parameters can be tailored according to their application.A novel battery design was tested with anode and cathode fabricated side by side in a planar arrangement. Electrode width and depth as well as electrolyte thickness are the main design parameters to achieve sufficient current capability which is required for wireless sensor nodes.

Reactive ion etching characteristics of epitaxial Si1−xGex layers in SiCl4/Cl2/N2 plasma are investigated by different diagnostic techniques, such as Auger electron spectroscopy, X‐ray photoelectron spectroscopy, and atomic force microscopy. Surface morphology and stoichiometry are influenced by the dry etching process. A slight Ge enrichment at the etched SiGe films is explained by the different volatility of the corresponding chlorides. Moreover, a procedure which allows an exactly determined etch stop in a thin buried SiGe alloy — as a necessary requirement for the following surface analysis — is introduced.

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