Conductive nanocrystalline graphite has been deposited using plasma-enhanced chemical vapour deposition at 750 °C, directly onto silicon substrates without any catalyst and fabricated into micromechanical membrane and beam structures. Using the buckling profile of the membrane and beam structures, we measure a built-in strain of-0.0142 and through wafer-bow measurement, a compressive stress of 436 MPa. From this we have calculated the Young's modulus of nanographite as 23.0 +/-2.7 GPa. This represents a scalable method for fabricating nanographite MEMS and NEMS devices via a microfabrication-compatible process and provides useful mechanical properties to enable design of future devices.

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In this work a Quasi-Concertina (QC) spring capable of a high linear range, large deflections, high out-ofplane compliance, and low in-plane compliance for MEMS applications is presented. These features are essential for high accuracy out-of-plane measurements such as those required in force-displacement measurements in self-sensing atomic force microscopy (AFM) probes or molecular mass sensors. The spring constant and first mode resonant frequency of the spring was determined analytically and verified numerically. The QC springs were microfabricated using a purposely developed stiction free process. Force-displacement tests on the QC springs have shown them to be in good agreement with the analytical and finite element analysis performed. The measurement results show that the QC springs fabricated have a spring constant of 5.5 N/m, 0.129 N/m, and 0.156 N/m, remain 99 % linear to a deflection of 100 µm, 1080 µm, and 931 µm respectively, and can have a total deflection before fracture of as much as 8000 µm.

In an effort to produce more cost effective diamond to metal interfaces, mono-and polycrystalline diamond powders were coated with nickel alloys using electroless chemical deposition techniques. Ni-P and Ni-B coatings were deposited using an acidic and an alkaline solution respectively. These deposition procedures were preceded by a thermal surface functionalisation step and a sensitisation step using a Pd-Sn colloidal solution. Imaging by SEM and chemical analyses show uniform coverage of the coating, independent of diamond's crystalline planes, and having thicknesses consistently ,200 nm.

In this work, we present the development of a novel Quasi-Concertina (QC) microelectromechanical systems (MEMS) force-displacement (F-D) sensor with a resolution as small as 5.6 nN, and 1.25 nm, and a range of as much as 5.5 x 10-3 N, and 1000 µm. The performance of the microfabricated proof-of-concept QC MEMS devices are in good agreement with our analytical and numerical estimates. F-D sensors with these attributes will enable the mechanical properties of biological phenomena to be continuously measured over large F-D ranges without the need to alter the measurement instrument.