A combined EPR and modulated photocurrent study of native defects in Bridgman grown vanadium doped cadmium telluride : the case of the tellurium antisite

David Verstraeten (1, 2) , Christophe Longeaud (3) , A. Ben Mahmoud , H. J. von Bardeleben (4) , Jean-Claude Launay (1) , Oudomsack Viraphong (1) , Ph. C. Lemaire (2)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 CSL - Centre Spatial de Liège
3 LGEP - Laboratoire de génie électrique de Paris
4 GPS - Groupe de Physique des Solides

The electrical and photoconductive properties of Bridgman grown vanadium–zinc co-doped CdTe bulk crystals are strongly influenced by one native intrinsic defect previously attributed to the Te vacancy. In order to identify this defect and control its formation mechanism, a correlated electron paramagnetic resonance (EPR) and modulated photocurrent (MPC) study has been made. The results obtained allow us to attribute this defect to the TeCd antisite, a double donor. By EPR and MPC its +/2+ level position has been determined to Ec - 0.20 eV. Four other centres of minor concentrations were characterized by MPC in as-grown crystals. From the MPC results the density of states for CdTe:V materials has been determined.

Mots clés: Crystal growth; Bridgman method; Vanadium; Calcium telluride; Antisite; Modulated photocurrent; Electron paramagnetic resonance

Domaines: Matériaux

David Verstraeten, Christophe Longeaud, A. Ben Mahmoud, H. J. von Bardeleben, Jean-Claude Launay, et al.. A combined EPR and modulated photocurrent study of native defects in Bridgman grown vanadium doped cadmium telluride : the case of the tellurium antisite. Semiconductor Science and Technolgoy, 2003, 18 (11), pp.919-926. ⟨10.1088/0268-1242/18/11/303⟩. ⟨hal-00182645⟩