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Faradaic current during a local oxidation using an atomic force microscope was studied. The intensity of the measured faradaic current was increased with increasing bias voltage applied to a cantilever, resulting in fabrication of larger size of nano-oxide structures on Si substrates. On the other hand, an excess current (over current) that was considered not to contribute the oxidation reaction was observed noticeably in the local oxidation of NiFe thin films. It was found that the excess current could be suppressed by depositing insulating oxide layers on the surfaces. The surface oxide layers were also advantageous for stable existence of meniscus promoting the local oxidation because of their hydrophilic properties. This method of capped oxide layers is significant for stable performance of the local oxidation technique fabricating nanostructures and nano-devices.

A local oxidation technique using an atomic force microscope (AFM) was studied. The reaction current passing through the AFM tip was measured in order to evaluate its dependence on the resistivity and surface condition of the samples. The current efficiency actually contributing the oxidation reaction was about 0.5 for a Si substrate. The ratio was constant regardless of the tip scan speed. As for NiFe thin films, the current was higher and the current efficiency was lower than those of the Si substrate. The Al2O3 capped layer on the NiFe thin films reduced the excess current, which did not contribute to the oxidation.

Magnetic and self-heating properties of various size NiFe2O4 (7.7-242.0 nm) were evaluated. The self heating temperature of each sample measured by applying ac magnetic field was affected by its magnetic property. The particle size dependence was also explained by the magnetic properties of the samples. At the lower frequency, the self heating was contributed by hysteresis loss. The ac magnetization process was also evaluated and the result could clarify the origin of self-heating. The 7.7 nm particle was heated by relaxation losses by the applied field at higher frequency. The energy efficiency of a magnetic field to generate self heating was analyzed. It was found that the particle of 130.7 nm exhibited the highest temperature rise and heat generation efficiency for the applied field of low amplitude and frequency.

The direct modifications of magnetic domain structures and magnetic anisotropy in Co-based nanostructures were studied. A Co rectangular structure of 5.1 µm length × 0.8 µm width was fabricated from a 15-nm-thick Co thin film deposited on a Pt layer on a SiO2/Si substrate by conventional processes of electron beam lithography and lift-off. The magnetic domain structure of the Co rectangle was divided by atomic force microscope (AFM) nano-oxidation. It was found that the magnetic domain structures could be controlled by AFM lithography. It was also proposed that the magnetic anisotropy could be directly modified by the nanolithography technique.

By measuring the voltage from the source electrode of the TEG-TFTs, the dynamic characteristics of TFT-LCDs have been analysed. It was clearly determined that the V rms decrement depends on the increase in the delay time of the gate signal. Under the H-reversed half-line driving method, both the time lag between the drain and the gate signal and the size of TFTs were both optimized. We were able to obtain these results on the condition that τdelay was equal to 1/3 of the on-time of the gate signal.

Remarkably enhanced resonant microwave transmissions have been found to take place in Fe78Si10B12 and Fe4.7Co70.3Si10B15 metal-metalloid foils corresponding to the FMR absorption at room temperature. The resonant transmission which takes place in the non-magnetostrictive Fe4.7Co70.3Si10B15 foil suggests that the magnetoelastic coupling is not necessarily responsible for the resonant transmission, contrary to previous reports.