Long Slender Piezo-Resistive Silicon Microprobes for Fast Measurements of Roughness and Mechanical Properties inside Micro-Holes with Diameters below 100 µm oleh Uwe Brand, Min Xu, Lutz Doering, Jannick Langfahl-Klabes, Heinrich Behle, Sebastian Bütefisch, Thomas Ahbe, Erwin Peiner, Stefan Völlmeke, Thomas Frank, Bodo Mickan, Ilia Kiselev, Michael Hauptmannl, Michael Drexel