Effects of annealing on magnetic properties of new ferromagnetic semiconductor (In, Al, Mn)As

The effects of low-temperature (210/spl deg/C-290/spl deg/C) annealing on the microstructure, lattice constant, and magnetic properties of (In/sub 0.52/Al/sub 0.48/)/sub 0.91/Mn/sub 0.09/As grown by low-temperature molecular-beam epitaxy were studied. The results show that low-temperature annealing has little influence on the crystalline structure and interface quality of (In/sub 0.52/Al/sub 0.48/)/sub 0.91/Mn/sub 0.09/As epilayer. In contrast, both the lattice constant and Curie temperature of (In/sub 0.52/Al/sub 0.48/)/sub 0.91/Mn/sub 0.09/As are found to be strongly dependent on the annealing temperature. The lattice constant linearly decreases with increasing annealing temperature; while the Curie temperature increases with increasing annealing temperature up to 250/spl deg/C, and then abruptly decreases upon further annealed at 270/spl deg/C and 290/spl deg/C.