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We investigate the role of a TiN film on epitaxial growth and crystal quality in the void‐assisted separation (VAS) method. Plan‐view TEM images show the TiN film contains numerous nanometer‐scale holes, resulting in a nano‐net structure. X‐ray rocking curve data show the crystal quality of GaN layers on the TiN nano‐net is very high, having the tilt/twist angles of 60/90 arcsec. Numerous small GaN islands were generated on the TiN nano‐net in the beginning of the growth. These islands having crystal facets may introduce the dislocation bending. We show that the TiN film plays a very important role in improving the crystal quality in the VAS method.

A novel series of ferroelectric liquid crystals with a¯uorinated asymmetric frame were synthesized by utilizing optically active (S)-2-, (S)-3-, (S)-4-and (S)-5-¯uoroalkanols prepared from corresponding (R)-1,2-epoxyalkanes. Their mesomorphic and physical properties, such as spontaneous polarization, optic tilt angle and response time, were investigated systematically in a series of homologous compounds having the chiral centre at di erent positions on tails of various lengths. All the compounds exhibited the chiral smectic C phase in a wide range of temperatures and were found to possess a fast response time in spite of the small magnitude of the spontaneous polarization.

The mechanical characteristics of iron-containing nanosprings (Fe-containing nanosprings) fabricated by focused-ion-beam chemical vapor deposition (FIB-CVD) using a ferrocene (C10H10Fe) source gas were investigated. The shear and Young's moduli were 34 and 92 GPa, respectively. We also evaluated the annealing effect of Fe-containing nanosprings and observed a droplet containing Fe and Ga on the nanospring after annealing at 600 °C. The spring constant rapidly decreased after annealing at 600 °C. By scanning electron microscopy energy–dispersive X-ray spectroscopy (SEM–EDX) and transmission electron microscopy energy–dispersive X-ray spectroscopy (TEM–EDX) line analysis, it was confirmed that the decrease in the spring constant was due to Ga removal.