[Show abstract][Hide abstract] ABSTRACT: Using physical vapor deposition (PVD) method, the (cBN/nano-diamond)3 multilayer film with phase purity, high hardness and low residual stress was synthesized on silicon substrates supported by a thick nano-diamond buffer. This method presented is characteristic with the direct cBN growth on diamond without soft, non-cubic BN interface layers; the synthesis of multilayer films with extraordinary adhesion to the substrates and higher hardness than a cBN single film, and the stress of the multilayer film can be reduced to only one forth of that of a cBN single film. These prime technological properties open the route to the mechanical exploitation of cBN films.
[Show abstract][Hide abstract] ABSTRACT: Nanocubic boron nitride/nanodiamond ( N -cBN/ND) multilayer structures with each alternating layer being ∼100 nm thick have been prepared by magnetron sputter and microwave plasma enhanced chemical vapor depositions. These multilayers exhibit remarkable properties, in particular, the mechanical properties. The multilayer structure is characteristic with (i) extreme hardness (82 GPa ) considerably surpassing the values of the individual materials from which the multilayer is composed, (ii) high surface smoothness, (iii) significantly reduced film stress when compared with a single cBN layer of equivalent thickness, and (iv) great chemical stability. The N -cBN/ND multilayers developed have therefore important implications in mechanical and chemically resistant applications.
[Show abstract][Hide abstract] ABSTRACT: Cubic boron nitride (BN) films with improved crystallinity are deposited by physical vapor deposition at an extremely low substrate bias (−35 V). The films are characterized by UV Raman in association with Fourier transformed infrared (FTIR) spectroscopy. The influences of bias voltage and film thickness on the characterizations are investigated. UV Raman, in contrast to FTIR, is demonstrated to be a more powerful tool with high sensitivity for quantitative and/or qualitative evaluation of the phase purity and crystallinity, especially as the film thickness increases. Hexagonal BN inclusions (less than 1%), not evident in FTIR, are clearly revealed by UV Raman analysis.