Fabrication and characterization of diamond nanotips for high resolution electrical scanning probe microscopy

Scanning probe microscopy has become a fundamental tool in the development of nanoelectronic devices, thanks to its versatility in measuring physical properties with nanometric resolution. Doped diamond tips are commonly used in electrical scanning probe microscopy modes where contact with the sample is needed, such as scanning spreading resistance microscopy and conductive atomic force microscopy. Molded diamond tips show good performances in electrical SPM setups, but the resolution and ability to image high aspect ratio structures are hindered by the fixed pyramidal shape; for this reason, a dry etching technique was developed at IMEC in order to sharpen molded diamond tips and overcome their limitations. In this thesis, sharpened tips were fabricated and characterized: optimal process parameters were found, the yield of the recipe was studied, and evaluation conductive AFM measurements were performed. Scanning electron and transmission electron microscopy were then used to investigate the role of masking particles in the tip formation process. Using the gathered information, deposition of masking material was carried out in order to better control the masking of sharp structures.