A comprehensive review is presented on the advances achieved in past years on fundamental and applied materials science of diamond films and engineering to integrate them into new generations of microelectromechanical system (MEMS) and nanoelectromechanical systems (NEMS). Specifically, the review focuses on describing the fundamental science performed to develop thin film synthesis processes and the characterization of chemical, mechanical, tribological and electronic properties of microcrystalline diamond, nanocrystalline diamond and ultrananocrystalline diamond films technologies, and the research and development focused on the integration of the diamond films with other film-based materials. The review includes both theoretical and experimental work focused on optimizing the films synthesis and the resulting properties to achieve the best possible MEMS/NEMS devices performance to produce new generation of MEMS/NEMS external environmental sensors and energy generation devices, human body implantable biosensors and energy generation devices, electron field emission devices and many more MEMS/NEMS devices, to produce transformational positive impact on the way and quality of life of people worldwide.
Introduction: Insertion of N atoms at a nanoscale subsurface depth in single-crystal diamond (SCD) may enable new generations of quantum electronics devices. In this sense, it is critical to understand the interaction between implanted N atoms and C atoms in the diamond lattice.Methods: The investigation of the interaction of N atoms with SCD at the atomic scale using X-ray photoelectron spectroscopy (XPS) analysis involves in situ bombardment of the SCD surface with relatively low-energy (5,000 eV) N2 ions. In situ XPS analyses of SCD and highly oriented pyrolytic graphite (HOPG) before and after N-atom implantation are compared with published XPS analyses of C-N materials (e.g., g-CN, N in poly/single-crystal diamond).Results: The analyses revealed three N 1s peaks at 398–399 eV (N1), 399–400.5 eV (N2), and 401–403 eV (N3), with the N1 and N2 peaks assigned to C-N bonds and an N3 peak inaccurately assigned, in prior publications, to N-bonded contaminants (e.g., O, NH). In situ cleaning of the SCD and HOPG surfaces prior to N-atom implantation was performed to eliminate all atmospheric contaminants. This cleaning process revealed that the N3 peak is associated with N-C-bonded atoms and not the C-O/NH linkage, as previously suggested. Ex situ high resolution transmission electron microscopy (HRTEM) studies of N-implanted SCD show a defect-structured subsurface region.Discussion: An important side effect of the relatively low-energy N implantation in SCD is the formation of a 5–8 nm electrically conductive surface layer, an effect that may open the pathways for future research in diamond-based micro- and nano-electronics.