Search

Abstract: Cathodoluminescence investigations were carried out on CdTe and Cd0.96Zn0.04Te crystals, to identify the dominant acceptor bound exciton (A0,X) and the free electron-to-bound acceptor (eA0) transitions in these crystals. Temperature dependent studies confirm the free electron-to-bound acceptor transition (eA0) character of the 1.576eV emission observed in our CdTe crystals. The broad emission band in the energy range 1.4–1.55eV (often called the defect band in CdTe), which was present in our CdTe crystal, was absent in our Cd0.96Zn0.04Te crystals (having a low rocking curve half-width of 40arcsec) and seems to be related to structural defects (such as dislocations) in the crystal. [Copyright &y& Elsevier]

Cathodoluminescence investigations on bulk undoped semi-insulating GaAs samples taken from different sources reveal the presence of a deep level emission at 0.9 eV at 77 K, with a narrow full width at half maximum of 8 meV. The temperature-dependent and beam-parameter-dependent studies indicate that, the probable origin for this emission may be some nanocluster/quantum-dot like structures with a band gap of 0.9 eV, present inside the semi-insulating GaAs crystal lattice. One possibility for such structures in semi-insulating GaAs are clusters/nanoprecipitates of arsenic. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]