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We have demonstrated a new technique to transform bulk materials into one-dimensional nanostructures. We have shown that p-type Si nanotubes (SiNTs) can be grown by a simple dual RF plasma treatment of p-type Si substrates at 500 • C. These SiNTs have diameters of ∼50-80 nm with tubular wall thickness of ∼10-15 nm. The use of Cu vapor and reactive plasma has enabled the growth of these SiNTs instead of Si nanowires.

We describe a fibre interferometer for making non-contact differential height measurements of machined metal surfaces without removal from the machine tool. The system comprises a probe which produces two small laser spots (∼ 7 µm diameter, 3 mm apart) on the surface, an optical fibre addressing lead and signal processing unit incorporating an optical source and detector. The probe is an extrinsic fibre optic Michelson interferometer whose arms terminate in the laser spots on the test surface, and the signal processing unit calculates the difference in local surface height between the two spots. Differential height profiles of machined aluminium surfaces and optical mirror surfaces are presented.

Standard ellipsometry is usually applied for the evaluation of an optical isotropic system, but it is insufficient to analyze light reflected from an anisotropic system such as a liquid crystal (LC) cell. In order to analyze the light reflected from the LC cell, the standard ellipsometry system combined with the photo elastic modulator was extended to renormalized ellipsometry by introducing the definition of the renormalized reflection coefficients without any modification of the conventional experimental procedure. The experimental results such as the ellipsometric angles versus the rotation angle of the LC cell and the dependence of the ellipsometric angles on the applied electric field were in good agreement with the theoretical results based on renormalized ellipsometry. From these results, it was confirmed that renormalized ellipsometry was quite a useful technique to analyze the totally reflected light from the LC cell.