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%0 Thesis %A Jaschinsky, Philipp %T Kombinierte Rasterelektronen- und Mehr-Spitzen-Rastertunnelmikroskopie als Methode zur Ladungstransportmessung im Nanometerbereich %C Aachen %I Publikationsserver der RWTH Aachen University %M RWTH-CONV-124002 %P 116 S. : Ill., graph. Darst. %D 2007 %Z Zsfassung in dt. und engl. Sprache %Z Aachen, Techn. Hochsch., Diss., 2007 %X Charge transport measurements on the nanometer scale are presented in this work. For these measurements, a combination of a scanning electron microscope (SEM) and a scanning tunneling microscope (STM) was used in ultrahigh vacuum environment. In order to perform vertical and lateral transport measurements, a double-tip STM was developed. The double-tip STM is described in this work. The design of this double-tip STM is based on the well-proven beetle-type design. It makes it possible to coaxially combine two beetle-type STM with each other in a small space. Due to this new design concept, it was possible to construct the double-tip STM very compactly so that the resolution and the freedom of movement of the STM tips are comparable to those of a single-tip beetle-type STM. The imaging capabilities of the double-tip STM will be demonstrated by atomically resolved pictures of the Si(111)-7x7 surface, obtained with each tip. The resolution limit of the SEM was determinated as approx. 50 nm. Furthermore, it is shown that the interaction of the SEM and the double-tip STM functions correctly. To this end, the two STM tips were brought close together, while being monitored by the SEM. The two STM were then able to image the same area at the Si(111) surface. The charge transport measurements presented here are subdivided into vertical and lateral transport. New ohmic nanocontacts, based on low-temperature-grown GaAs, were investigated for the vertical transport measurements. For this purpose, one STM tip was brought into contact with these devices. Additionally, GaAs-based resonant tunneling diode structures with side lengths of down to 40nm were contacted and characterized. In addition, a field effect was measured by using the second STM tip as a gate electrode. The Si(111)-7x7 surface was used for the lateral transport measurements. In order to avoid damaging the STM tips and the 7x7-surface, the distance-dependent 2-point measurements were performed in tunneling contact. The results were compared with a 2-point model for 3D and 2D charge transport. This comparison showed better correlation with the results for the 2D model than for the 3D model. %K Rastertunnelmikroskopie (SWD) %K Rasterelektronenmikroskopie (SWD) %K Ultrahochvakuum (SWD) %K Ladungstransport (SWD) %K Festkörperoberfläche (SWD) %F PUB:(DE-HGF)11 %9 Dissertation / PhD Thesis %U https://publications.rwth-aachen.de/record/62433