Isoelectronic oxygen-related defect in CdTe crystals investigated using thermoelectric effect spectroscopy
Abstract
An oxygen-related defect was studied in nominally undoped CdTe crystals grown by the high pressure Bridgman technique using thermo-electrical effect spectroscopy and first-principles band structure calculations. Based on the linear relationship between the oxygen concentration and the emitted charge from the defect level with an ionization energy E=0.184±0.011 eV and a capture cross section σ=(7±4)×10-17 cm2 we show that the defect is an oxygen complex. Using thermal annealing experiments we show that the defect complex contains cadmium vacancies. Using first-principles band structure calculations we assign the defect level to the second ionization level of the isoelectronic oxygen-cadmium vacancy pair (OTe-VCd)-/2-.
- Publication:
-
Physical Review B
- Pub Date:
- February 2004
- DOI:
- 10.1103/PhysRevB.69.075210
- Bibcode:
- 2004PhRvB..69g5210A
- Keywords:
-
- 71.55.-i;
- 81.70.Fy;
- 78.60.Kn;
- 78.55.Et;
- Impurity and defect levels;
- Nondestructive testing: optical methods;
- Thermoluminescence;
- II-VI semiconductors