Nanostructuring surfaces with slow multiply-charged ions

Abstract

With the shrinking of semiconductor devices surface features and structuring become increasingly important. Generally, fast ions are used for modification of surfaces via ion beam writing. Their kinetic energy is not only dissipated close to the surface but also in deeper layers of the material. Associated radiation damage could become a problem in the production of novel 3D micro- and nanoelectromechanical systems (MEMS and NEMS). Slow (< 1keV) multiply-charged ions as opposed to fast ions are a new tool for gentler structuring of surfaces at the nanometer-scale. The substrate is modified only at and slightly below the surface, opening the possibility of controlling electronic properties at the nanometer scale, vertically and horizontally. Materials under investigation are highly orientated pyrolytic graphite, single crystal insulators (quartz, mica, aluminum oxide), hydrogen-terminated single-crystal silicon, AsSe- and Se-glass and mylar foils. The materials modified by the ion irradiation are investigated with scanning probe microscopy (AFM, STM) in ultrahigh vacuum and in ambient conditions.