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Nanoelectromechanics is a growing field. Nevertheless, the static deflections of nanoelectromechanical systems are hardly investigated. Since these are required for most nanomechanical tools, e. g. nanotweezers, they are dealt with in the work presented. A new fabrication scheme to build fully freely suspended structures out of silicon-on-insulator wafers was developed to get nanostructures with a hole-aperture right beneath them. The expected deflections of the fabricated double cantilever system were calculated using elasticity theory. To measure the quasistatic deflections of these nanosystems under a bias voltage, a scanning confocal optical microscope was used in conjunction with demodulation of the reflected signal. This worked for freely suspended as well as fully freely suspended structures and the system was operated under ambient conditions. Using this technique, signals at the first, second, and third harmonic of the excitation frequency could be detected. These were correlated to the deflection in horizontal and vertical direction. The vertical deflection is a parasitic one due to the vicinity of the substrate, since the system was designed to show a horizontal deflection, only. The fully freely suspended structures, in contrast, do not show deflections resulting from forces towards the substrate. To distinguish between the two directions of motion as well as to get a better understanding of the interference-dominated scanning images of the structures having a substrate beneath, numerical simulations of the imaging were performed. These reproduce the images as well as the demodulated signals quite well. The sensitivity of the optical demodulation measurement was shown to be 6 pm /Sqrt(Hz) (rms), a deflection of about 2 angstrom could be proven. Using the same set-up in a non-scanning way, resonances of the deflected structures were identified. The fabrication as well as detection schemes are fundamental for the development of nanotweezers capable of repositioning nano-scaled objects. Additionally, some calculations concerning the melting that occurred to the contacted nanostructures under investigation by a scanning electron microscope are presented. The electroluminescence that one of the silicon nanostructures accidentally showed is interpreted in terms of the analogy to spark-processed silicon. In conclusion, scanning confocal optical microscopy is shown to be a highly sensitive as well as non-destructive technique to investigate quasistatic deflections of nanoelectromechanical systems in the angstrom range.