A NiO–Y₂O₃ stabilized ZrO₂ (NiO–YSZ) supported tubular solid oxide cell, which consists of a La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ (LSGM) dip-coated electrolyte film and Sm_0.5Sr_0.5CoO_3−δ (SSC) air electrode, was prepared and its power generation and electrolysis performance in the intermediate temperature range were investigated. Compared to other rare earth oxides studied, infiltration of Ce nitrate into the substrate was the most effective for increasing cell performance in the case of 2 M infiltration. Moreover, it was found that the infiltration of a higher concentration of the Ce solution increased the maximum power density, because both IR loss and overpotential were significantly decreased. The maximum power density of the cell was 0.95 and 0.42 W cm⁻² at 873 and 773 K, respectively at 3 M Ce nitrate infiltration. The long-term stability of the cell was also measured by using the cell infiltrated with 1.5 M Ce, and a stable power generation performance was demonstrated up to 100 h. The steam electrolysis performance of the cell using Ce infiltration was further studied and it was found that Ce also contributes to higher current density in SOEC operation and 1.07 A cm⁻² at 1.6 V was achieved at 873 K using 2 M Ce infiltration.

In order to achieve high removal rate and high-quality processing on SiC wafer, we carried out the CMP processing experiment with the new type CMP machine (Bell-jar) by using the slurry with the addition of strong oxidant (KMnO₄). It was found that the high speed CMP processing was achieved by controlling the concentration of KMnO₄ in the slurry, the pH of slurry and the processing atmosphere. By using the slurry with the addition of KMnO₄ of 0.1mol/L, the removal rate was the fastest up to 1019nm/h in the fixed pH of 6. By use of the slurry of pH 3, the removal rate of C-face of SiC wafer was 1695nm/h On the other hand, the fastest removal rate of Si-face of SiC wafer was only 51nm/h by using the slurry whose pH is 7. In the open air atmosphere, the removal rate was 915nm/h, which was higher than that at the higher and lower atmospheric pressure.

A micro-tubular type solid oxide fuel cell was prepared by using a NiO-YSZ anode support tube and La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ (LSGM) electrolyte film which was prepared by dip-coating and co-sintering process. Since a large electric resistance loss (IR loss) was observed at the cathode side, LSGM porous layer was inserted between electrolyte and cathode resulting in much increased power density. The prepared cell using Sm_0.5Sr_0.5CoO_3-δ (SSC) cathode layer on the porous LSGM layer exhibited almost theoretical open circuit voltage (OCV) of ca.1.1 V and a maximum power density (MPD) of ca. 0.782 and 0.1 W/cm² at 973 and 773 K, respectively, in fuel cell operation. The increased MPD by an inserting the porous LSGM layer can be explained by an increase in mechanical contact and cathodic reaction area. In addition, the electrolysis operation of the prepared LSGM tubular cell with an atmosphere of 20% steam and 30% H₂ was examined and it was found that the prepared tubular type LSGM cell showed a reasonably large electrolysis current. The current density of the cell with and without LSGM porous layer was 1.47 and 1.11 A/cm² at the applied potential of 1.5 V, 973 K. As a result, it was found that the prepared LSGM electrolyte cell can be used as a reversible type cell with reasonable power density in SOFC operation and high H₂ formation rate in electrolysis operation by deposition of an LSGM porous layer on the Air electrode side.

Tubular type Solid Oxide Fuel Cells (SOFCs) using La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ film was prepared by dip coating and co-sintering method. Although it is known that LaGaO₃ doped with Sr and Mg denoted as LSGM has reactivity with NiO in substrate and nickel diffusion into LSGM film was occurred during co-sintering. Nickel diffusion can be decreased by using Ce_0.6La_0.4O₂-TiO₂ (Ti-LDC) and Ce_0.6Mn_0.3Fe_0.1O₂ (CMF) buffer bilayer. In this study, LSGM/Ti-LDC/CMF film was prepared on NiO-Sr_0.55La_0.3TiO₃ (SLT) substrate. Since nickel is reacted with Ti⁴⁺ in substrate, nickel diffusion was significantly suppressed by using SLT for anode substrate and the cell using LSGM film with suppressed amount of Ni diffusion shows reasonable high open circuit potential and power density. The single SOFC using NiO-SLT substrate shows the maximum power density of 0.412, 0.165 and 0.065 W/cm² at 973, 873, and 773 K, respectively. Although anodic overpotential is almost the same with that of the cell prepared on NiO-Ce_0.8Gd_0.2O₂ (GDC) substrate, anodic IR loss became much smaller on NiO-GDC at low temperature and this may be assigned to the high conductivity of GDC at low temperature. However, at high temperature, because of small overpotential, the cell using LSGM film on NiO-SLT anode substrate shows higher power density than that of NiO-GDC cell.