Far infrared photoconductivity and absorption measurements were performed on isotopically controlled 76Ge samples that were neutron irradiated to produce 77Se through double beta decay. The spectra exhibit ground state to bound excited state transitions which place the first ionization level of Se at Ec-0.2688 eV. Hall effect measurements on compensated Ge:Se single crystals yield the second ionization level in the lower half of the band gap at Eν+0.17 eV. Our experiments offer the first unambiguous identification of the deep donor level formed by single Se atoms on Ge lattice sites and verify earlier findings.
- A. semiconductor
- C. impurities in semiconductors
ASJC Scopus subject areas
- Condensed Matter Physics
- Materials Chemistry