Mask-less nano-structuring of hydrogen terminated diamond using localized field emission scanning probe lithography (FE-SPL)

Sensing and manipulating a particle's spin promise the development of more energy efficient and ultra-fast devices. Diamond is a promising candidate for spintronics and quantum systems, where nano-structuring of diamond surfaces on nanometer length scales is required. Here, direct-write modification of a diamond surface at sub-50 nm resolution is demonstrated. This is achieved with an atomic force microscope tip used as a spatially localized field emission source or so-called field-emission scanning probe lithography on a sample in ambient conditions, which are rendered conductive only through the surface conductivity of hydrogen-terminated diamond. Mask-less direct structuring of the diamond surface is observed, creating features of depth in the range of 4-8 nm and linewidths of 70-150 nm, as well as the desorption of hydrogen from the surface achieving minimum linewidths of 40 nm. Both the linewidth and depth of etching appear to depend on the energy of emitted electrons and the resulting electron exposure dose. These findings demonstrate the possibility of controllably nano-structuring diamond surfaces with features over micrometer length scales and with sub-50 nm resolution, while held under ambient conditions.