Showing papers by "Tetsu Tanaka published in 1990"

U-grooved SIT CMOS technology with 3 fJ and 49 ps (7 mW, 350 fJ) operation

Abstract: Static induction transistor (SIT) CMOS is analyzed by a circuit simulation method. According to the results, the propagation delay time of the SIT CMOS could be represented as the ratio of the load capacitance to the transconductance. The U-grooved structure plays an important role in the fabrication of MOS SIT with large transconductance and small parasitic capacitance. U-grooved SIT CMOS has been fabricated by anisotropic plasma etching, and its switching speed has been evaluated by a 31-stage ring oscillator. A minimum rho - tau product of 3 fJ/gate has been obtained for a design rule of 1- mu m channel length. A minimum propagation delay time of 49 ps/gate has also been obtained at a dissipation power of 7 mW/gate, which corresponds to a rho - tau product of 350 fJ/gate. >

Magnetic and Magnetooptical Properties of Mn(Sb-Bi) Thin Films Fabricated by the Interdiffusion Method

Abstract: NiAs-type Mn(SbBi) alloy films, with c-axes oriented perpendicular to the film surface, were obtained in the composition range 45 ≪ Mn ≪ 65 at%, Bi ≪ 10 at% by first forming an oriented SbBi layer by vapor deposition and annealing, then depositing an Mn layer onto this SbBi layer at an appropriate substrate temperature, and finally annealing at temperatures up to 500°C. Several different phases appeared in these films, the matrix of which was the NiAs type Mn (SbBi) phase. It was found that the phases and lattice constants of Mn(SbBi) change on increasing the annealing temperature. Systematic experiments on the magnetic anisotropy constant Ku and Kerr rotation angle ? K were carried out for the Mn(SbBi) films. As a result, substitution of Bi for Sb led to 1) an increasing K u value, and 2) a change in the wavelength dependence of ? K . The maximum observed values of K u and ? K were 4.5 × 106 erg/cm3 and 0.5° at H ex = 7 kOe.