Well-aligned nanotip arrays were fabricated by electron cyclotron resonance (ECR) plasma process using gas mixtures of silane, methane, argon, and hydrogen. The resultant tips have nanoscale apexes (∼1 nm) with high aspect ratios (∼50), which were achieved by simultaneous SiC nanomask formation and dry etching during ECR plasma process. This technique was applied to a variety of substrates such as silicon, polycrystalline silicon, gallium nitride, gallium phosphide, sapphire, and aluminum, indicating its general applicability. High-resolution transmission electron microscopy and Auger depth profile analyses revealed that the SiC cap, with Si:C ratio of 1:1, exhibited 3C−SiC and 2H−SiC structure on Si and GaP, respectively, with heteroepitaxial relationship. This one-step self-masked dry etching technique enables the fabrication of uniform nanotip arrays on various substrates over large area at low process temperatures, thereby demonstrating a high potential for practical industrial application.

The substantial amount of –OH groups attached to the Zn lattice has been correlated to the dominant c-axis orientation of the hexagonal ZnO crystals with wurtzite structure, which demonstrates two preferred first-order Raman peaks and also exhibits a distinct UV luminescence band due to the typical exciton emission or near-band-edge emission.

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Diamond thin films have outstanding optical, electrical, mechanical and thermal properties, which make these attractive for applications in a variety of current and future systems. In particular, the wide band gap, optical transparency and unusually high thermal conductivity of diamond thin films make them an ideal semiconductor for applications in current and future electronics. However, synthesis of diamond thin films with adequate quality remains a challenging task. Synthesis of diamond at low temperatures is even more challenging because of the difficulties in the nucleation and growth steps involved in diamond thin film deposition on a variety of substrates. Among the several deposition techniques for synthesising diamond films, plasma enhanced chemical vapour deposition is the most promising technique because of its potential for low temperature synthesis. Consequently, the first part of this paper reviews the current state of the nucleation and growth of diamond during chemical vapour deposition. A uniform and high nucleation density is a prerequisite for getting a good quality diamond film with significant growth rate. Also, since the process conditions for nucleation and growth steps are different, attempts are made in this review to identify the important parameters responsible for enhancing the nucleation and growth rates of diamond film. Describing the indispensable need for low temperature growth of diamond film, the second part of the paper reviews the research on the growth of diamond thin films at low temperatures. In spite of the slower kinetics at lower deposition temperatures, an attempt is made to identify the key processing conditions, which enhance the low temperature growth process. In addition, the mechanisms of diamond nucleation and growth are discussed based on the observations from in situ characterisation techniques such as Fourier transform infrared reflection absorption spectroscopy, real time spectroscopic ellipsometry and molecular beam mass spectroscopy.