We investigate effects of annealing on magnetic properties of a thick (Ga,Mn)As layer, and find a dramatic increase of the Curie temperature from 65 to 115 K by postgrowth annealing for a 500-nm (Ga,Mn)As layer. Auger electron spectroscopy measurements suggest that the increase of the Curie temperature is mainly due to diffusion of Mn interstitial to the free surface. The double-crystal x-ray diffraction patterns show that the lattice constant of (Ga,Mn)As decreases with increasing annealing temperature. As a result, the annealing induced reduction of the lattice constant is mainly attributed to removal of Mn interstitial.
Deng Jiajun;Zhao Jianhua;Jiang Chunping;Zhang Yan;Niu Zhichuan;Yang Fuhua;Wu Xiaoguang;Zheng Houzhi.Effect of Annealing on Structural and Magnetic Properties of a Thick (Ga,Mn)As Layer,Chinese Physics Letters,2005,22(2):466-468
