[8p-Z08-1~8] 10.4 Semiconductor spintronics, superconductor, multiferroics

▲ [8p-Z08-5] Spin transport in Si-based spin metal-oxide-semiconductor field-effect transistors: Spin drift effect in the inversion channel and spin relaxation in the n⁺-Si source/drain regions

〇(PC)Shoichi Sato^1,2, Shota Okamoto¹, Masaaki Tanaka^1,2, Ryosho Nakane¹ (1.Tokyo Univ., 2.CSRN)

Keywords:Semiconductor Spintronics, Silicon, MOSFET

Si-based spin metal-oxide-semiconductor field-effect transistors (spin MOSFETs) have been extensively studied as the key devices in next-generation electronics due to their spin-functional nonvolatile/reconfigurable characteristics. Although some previous experimental studies showed the basic operation, the MR ratio was lower than 1%, which is too small for practical applications. To clarify the detailed spin transport physics in Si-based spin MOSFETs and to improve the MR ratio, we construct analytical formulas that precisely take into account the n⁺-Si regions at source(S)/drain(D) electrodes as well as the spin drift effect in the inversion channel. The analytical formula was obtained by solving the one dementional spin drift-diffusion equation. We found that the injected spins are substantially flipped in the n⁺-Si regions even though their thickness (~5 nm) is far shorter than the spin diffusion length (~ 0.5 μm). [ref] S. Sato, M. Tanaka, R. Nakane, arXiv:2003.02415 (2020); Phys. Rev. B. in press.