The investigation of electrical contacts using newly designed nano-indentation manipulator in scanning electron microscope

Nano-indentation manipulator operated in SEM was constructed in order to investigate the electrical contacts on a nanometer scale. Then it is simultaneously possible to observe and control indentation movement and to measure the load force and electrical resistance. Particularly in order to investigate the influence of thick oxide layer on the electrical resistance during indentation, a tin substrate covered with thick tin oxide layer was indented by a tungsten probe. Electrical resistance, measured as a function of indentation depth and load force, drastically decreased in the region where concentric circular and radial cracks and tin penetration in the cracks were found. Resistance decrease was strongly related to the tin appearance on the surface through cracks. The results indicate that the nano-indentation manipulator is powerful tool for the nanometer scale research on electrical contacts.