Abstract: A spin transistor having wide ON/OFF operation margin and producing less noise is provided. The spin transistor includes a substrate having a channel, a source, a drain and a gate formed on the substrate. The source and the drain are formed to have magnetization directions perpendicular to the length direction of the channel. The ON/OFF operations of the spin transistor can be controlled by generating a spin-orbit coupling induced magnetic field to have a direction parallel or anti-parallel to the magnetization directions of the source and the drain.

Abstract: A 3 group-5 group compound ferromagnetic semiconductor, comprising one material ‘A’ selected from the group of Ga, Al and In and one material ‘B’ selected from the group consisting of N and P, wherein one material ‘C’ selected from the group consisting of Mn, Mg, Co, Fe, Ni, Cr and V is doped as a material for substituting the material ‘A’, the compound semiconductor has a single phase as a whole. The ferromagnetic semiconductor can be fabricated by a plasma-enhance molecular beam epitaxy growing method and since it shows the ferromagnetic characteristics at a room temperature, it can be applied as various spin electron devices.