Structural and electronic properties of Zn on a CdTe(001) surface

To understand CdTe doping with Zn, first-principle calculations are performed to obtain the various kinds of surface-structure for Zn on a CdTe(001) surface. A Te-terminated CdTe(001)-(2×2) surface structure with a 0.25 monolayer-coverage of Zn absorbing at the bridge sites is the most energetically favorable among the surface structures examined. For the Cd-terminated surface, a cadmium vacancy can form spontaneously. Zn atoms may also accumulate at the voids inside the CdTe film during subsequent growth, which may diffuse into Cd vacancies under specifically external conditions, i.e., the growth temperature, atmospheric pressure, etc.