Epitaxial growth and characterizations of quaternary alloy ferromagnetic semiconductor (In,Ga,Fe)Sb

摘要

Ferromagnetic semiconductors (FMSs) are promising materials for spintronics applications because of their high compatibility with the semiconductor technology. To realize practical devices operating at room temperature, both p-type and n-type FMSs with high Curie temperature (T_C>300 K) are required. Thus far, although the prototypical FMS (Ga,Mn)As has been intensively studied, it shows only p-type conduction with low T_C (≤ 200 K) [1]. Recently, we have successfully grown Fe-doped Ⅲ-Ⅴ FMSs with high TC;both p-type (Ga,Fe)Sb with TC=400 K [2] and n-type (In,Fe)Sb with TC=385 K [3]. For device applications of these new Fe-doped FMSs, we have to control their fundamental material properties, including the lattice constant, band structure, carrier type, T_C and magnetic anisotropy.