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KEYWORDS low temperature diamond deposition, diamond plates, LA MW PE CVD The crucial requirement for diamond growth at low temperatures, enabling a wide range of new applications, is a high plasma density at a low gas pressure, which leads to a low thermal load onto sensitive substrate materials. While these conditions are not within reach for resonance cavity plasma systems, linear antenna microwave delivery systems allow the deposition of high quality diamond films at temperatures around 400°C and at pressures below 1 mbar. In this work the co-deposition of high quality plates and octahedral diamond grains in nanocrystalline films is reported. In contrast to previous reports claiming the need of high temperatures (T ≥ 850 °C), low temperatures (320 °C ≤ T ≤ 410 °C) were sufficient to deposit diamond plate structures. Cross-sectional high resolution transmission electron microscopy studies show that these plates are faulty cubic diamond terminated by large {111} surface facets with very little sp 2 bonded carbon in the grain boundaries. Raman and electron energy loss spectroscopy confirm a high diamond quality, above 93 % sp 3 carbon content. Three potential mechanisms, that can account for the initial development of the observed plates rich with stacking faults, and are based on the presence of impurities, are proposed.

Glass and diamond are suitable materials for harsh environments. Here, a procedure for fabricating ultra-thin nanocrystalline diamond membranes on glass, acting as an electrically insulating substrate, is presented. In order to investigate the pressure sensing properties of such membranes, a circular, highly conductive boron-doped nanocrystalline diamond membrane with a resistivity of 38 mΩ cm, a thickness of 150 nm, and a diameter of 555 μm is fabricated in the middle of a Hall bar structure. During the application of a positive differential pressure under the membrane (0–0.7 bar), four point piezoresistive effect measurements are performed. From these measurements, it can be concluded that the resistance response of the membrane, as a function of differential pressure, is highly linear and sensitive.

Hexagonal boron nitride (hBN) nanowalls were deposited by unbalanced radio frequency sputtering system on (100)-oriented silicon, nanocrystalline diamond films, and amorphous silicon nitride (Si 3 N 4 ) membranes. The hBN nanowall structures were found to grow vertically with respect to the surface of all of the substrates. To provide further insight into the nucleation phase and possible lattice distortion of the deposited films, the structural properties of the different interfaces were characterized by transmission electron microscopy.Hexagonal boron nitride (hBN) has a structure similar to graphite, in which B and N atoms are bound alternatively in in-plane hexagonal rings forming two dimensional (2D) sheets, which are held together by van der Waals forces, forming the hBN lattice. hBN can be synthesized into nanostructured films, such as nanowalls, with tunable properties depending on the growth parameters, to make it insulating, highly compressible, or to improve its lubricity [1,5]. Grown hBN structures have so far shown a considerable number of defects and disordered BN phases, i.e. amorphous and turbostratic boron nitride (aBN and tBN), particularly at the initial stages of thin film growth. The presence of those phases is largely dependent on dynamics of chemical reactions at the substrate surface [1]. A substrate material that reduces these defective phases, creating a direct interface to the hBN phase, is therefore highly desirable.Many excellent properties of diamond, such as a negative electron affinity on hydrogen terminated surfaces, mechanical hardness, chemical inertness, and good thermal conductivity