Design of the 30nm FinFETs and Double Gate MOSFETs with the halo structure for suppressing the threshold voltage roll-off and improving the subthreshold swing at the same time is proposed for the first time. The performances of nano scale FinFETs and Double Gate MOSFETs with the halo structure are analyzed using a two-dimensional device simulator. The device characteristics, focusing especially on the threshold voltage and subthreshold slope, are investigated for the different gate length, body thickness, and halo impurity concentration. From the viewpoint of body potential control, it is made clear on how to design the halo structure to suppress the short channel effects and improve the subthreshold-slope. It is shown that by introducing the halo structure to FinFETs and Double Gate MOSFETs, nano-scale FinFETs and Double Gate MOSFETs achieve an improved S-factor and suppressed threshold voltage V_th roll-off simultaneously.

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The basic technology to measure rapidly the surface roughness of 3-dimensional cast metals using an optical non-contact method has been developed. In the experiment, the standard plates with surface roughness ranging from 100 μm to 400 μm for the evaluation of cast metal has been used. The standard plate is illuminated obliquely with the incident angle θ_i (=60°) and detected by CCD camera perpendicularly. An evaluated value F is calculated using the detected image. F is proportional to the surface roughness R_y when the standard plate is illuminated from both side at a right angle to inclined direction, and the plate is inclined with angles ranging from +25° to -25°. The surface roughness R_yis obtained by F with the error less than ±18% according to the proportional relationship between F and R_y.

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  Fe_100–xSi_x (x = 0, 2, 6, 10 at. %) alloy films are prepared on MgO single-crystal substrates of (001), (110), and (111) orientations at temperatures ranging between room temperature and 600 °C by using a radio-frequency magnetron sputtering system. The film growth behavior, the crystallographic properties, and the magnetic properties are systematically investigated. Fe-Si(001) single-crystal films with bcc structure are formed on MgO(001) substrates. The Fe-Si films deposited on MgO(110) substrates consist of epitaxial bcc(211) bi-crystals whose orientations are rotated around the film normal by 180° each other. Fe-Si films grow epitaxially on MgO(111) substrates with two types of bcc(110) variant whose crystallographic orientations are similar to the Nishiyama-Wasserman and the Kurdjumov-Sachs relationships. The orientation dispersion of Fe-Si film decreases with decreasing the Si composition, with increasing the substrate temperature, and with decreasing the index of the substrate crystallographic plane. The Fe-Si films deposited on MgO(001) and (110) show in-plane magnetic anisotropies reflecting the magnetocrystalline anisotropies of bulk Fe-Si alloy crystals. The Fe-Si films deposited on MgO(111) show nearly isotropic in-plane magnetic anisotropies that possibly come from the multiple variant structure. The coercivity decreases with increasing the Si composition and with decreasing the substrate temperature.

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