Growth and properties of (Ga,Mn)As on Si (1 0 0) substrate

Ferromagnetic (Ga,Mn)As epitaxial layers with zincblende structure have been grown on Si (1 0 0) substrates employing a three-step method using molecular beam epitaxy. Magnetic measurements reveal that the ferromagnetic transition temperature is 48 K for a layer with a lattice constant of 0.567 nm, which corresponds to a nominal Mn composition of 2%. When grown directly on Si without the three-step method, the same set of growth parameters results in a (Ga,Mn)As layer with a ferromagnetic order below 25 K. The difference of magnetic property between these two samples is attributed to the quality of the (Ga,Mn)As layer which originates from the different growth methods.