Interdiffusion mechanisms in CdTe/CdMgZnTe : N modulation-doped heterostructures

p-type modulation doping of CdTe-CdMgZnTe heterostructures, using nitrogen as a dopant, induces a strong interdiffusion of the quantum wells. Photolum inescence, secondary ion mass spectrometry, and x-ray diffraction measureme nts give a coherent description of the interdiffusion process: the destruct ion of the quantum wells occurs essentially by exchange of Cd and Mg atoms across the interface, while the Zn atoms stay in their lattice sites. We sh ow that the presence of nitrogen at the interface, which enhances the inter diffusion, is related to the diffusion of nitrogen and not to segregation. Additional mechanisms are observed at higher doping. (C) 2000 American Inst itute of Physics. [S0021-8979(00)03608-2].