An investigation was made of Te-related intrinsic defects in ZnS1–xTex thin films. First-principles calculations were performed for ZnS with Te as impurity atoms. The results showed that the substitutional incorporation of Te in group-VI sites cannot form defect states deep in the energy band gap of ZnS. On the other hand, the calculations of both Te antisite and interstitial defects resulted in deep-level states. X-ray photo-electron spectroscopy and time-of-flight secondary ion mass spectrometry were used to study the chemical structures of 3 molecular beam epitaxially-grown ZnS1–xTex samples, x{0.005, 0.019, 0.026}. An asymmetry was detected in the X-ray photo-electron spectra of both Te 3d3/2 and Te 3d5/2 core levels, which indicated that a small portion of the incorporated Te atoms was bonded to a more electronegative element. A peak at m/z of 158 was detected in the secondary ion mass spectrometry depth profiles of these samples and its characteristics match those of TeS components of the lattice matrix. This experimental evidence strongly supported the existence of Te antisite defects in the thin films. It was suggested that the highly luminescent centers in ZnS1–xTex thin films were possibly due to the deep-level states generated by Te anti-site incorporation.

Te Antisite Incorporation in ZnS1–xTex Thin Films. S.K.Chan, H.J.Liu, C.T.Chan, Z.Q.Zhang, W.K.Ge, I.K.Sou: Physical Review B, 2005, 71[19], 195421 (5pp)