GROWTH AND CHARACTERIZATION OF Be-CODOPED GaMnAs

III-V ferromagnetic semiconductor has attracted great attention as a potential application for spintronics due to a successful demonstration of spin injection from ferromagnetic GaMnAs into semiconductor. A conclusion so far in the GaMnAs system is the maximum incorporation of Mn up to ~ 5% with ferromagnetism below ~110 K. Higher Mn incorporation produces MnAs precipitates, and which has rather decreased the Curie temperature. In the meantime, the authors have shown that another III-V system of GaMnN reveals room temperature ferromagnetism in structures grown by MBE using a single GaN precursor.[1] In the subsequent attempt to further enhance the carrier concentration in the matrix of GaMnN solid solution by codoping nonmagnetic doping element of Mg [2,3], however, the saturation magnetization has dramatically enhanced even with a very small Mn concentration, but magnetotransport could not be observed due to relatively high resistivity or the semiconducting behavior of the layers. In this study, we present a study on Be-codoped GaMnAs including ferromagnetism and magnetotransport at room temperature.