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The time variation of the plasma parameters along with their spatial distributions were measured in pulse-modulated (PM) inductively coupled argon plasma via the phase delay harmonic analysis method (PDHAM). During the initial active-glow, the distributions of both the ion flux and the electron temperature in the plasma bulk have M-shaped profiles due to the antenna geometry. Then, while the plasma is approaching a steady state, the spatial distribution evolves into a profile with a convex shape. The effects of the antenna geometry and the time evolution on the distribution profile are lesser under low gas pressure, and diminish at the wafer level. The diffusion of the charged particles and the nonlocal electron kinetics account for these characteristics. It is observed that the initial distribution of the electron temperature is affected by the electron density distribution of the previous after-glow at the wafer level. The distribution profiles at different pulse frequencies were also measured. At higher pulse frequencies, the distribution profile is more frequently smoothed by diffusion during the after-glow, leading to higher uniformity.

For appling low temperature co-fired ceramics technology on NiZnCu ferrite with Ag electrode, the synthesis of nano-sized NiZnCu ferrite powders using metal nitrates and the fabrication of ferrite thick films by a doctor blade method were carried out. Microstructural analysis confirmed that nano-sized ferrite powders and fully densified thin films were successively fabricated. At a sintering temperature of 950 °C the magnetic properties of the ferrite thick film with 0.2 -0.3 mol Cu were close to those of bulk materials (permeability > 450, coercivity < 3 Oe).

We explore the effect of high-speed blade coating on electrical characteristics of conjugated polymer-based thin-film transistors (TFTs). As the blade-coating speed increased, the thickness of the polymer thin-film was naturally increased while the surface roughness was found to be unchanged. Polymer TFTs show two remarkable tendencies on the magnitude of field-effect mobility with increasing blade-coating speed. As the blade-coating speed increased up to 2 mm/s, the fieldeffect mobility increased to 4.72 cm2V−1s−1. However, when the coating speed reached 6 mm/s beyond 2 mm/s, the field-effect mobility rather decreased to 3.18 cm2V−1s−1. The threshold voltage was positively shifted from 2.09 to 8.29 V with respect to increase in blade-coating speed.

Physical and microstructural properties of Pungchon and Maggol limestone were investigated quantitatively during 50 cycles of artificial freezing and thawing test. There were decrease in dry weight and P,S-wave velocity, and increase in absorption rate in both rock types. Porosity, pore volume, equivalent diameter, throat thickness and pore orientation were analyzed using X-ray computed tomography images. Porosity increased, and initiation and expansion of pores were investigated as weathering progresses. Physical and microstructural variation in Maggol limestone was larger than that of Pungchon limestone because Maggol limestone has more pores and microcracks at initial state. As this study analyzes physical and microstructural properties of rock specimens comprehensively, it can be applied to further rock weathering study and can be used as fundamental data of construction and resource development in cold regions.