Gratulujemy prof. Damianowi Pucickiemu oraz innym współautorom opublikowania pracy "Effects of rapid thermal annealing on deep-level defects and optical properties of n-type GaAsBi alloys grown by molecular beam epitaxy at low temperature" wydanej w czasopiśmie Materials Science in Semiconductor Processing (IF=4,1). Wszystkim życzymy dalszych sukcesów naukowych.

Effects of rapid thermal annealing on deep-level defects and optical properties of n-type GaAsBi alloys grown by molecular beam epitaxy at low temperature

Ł. Gelczuk, J. Kopaczek, D. Pucicki, T. B.O. Rockett, R. D. Richards, R. Kudrawiec

The effects of rapid thermal annealing on the concentration and the type of deep-level defects and their influence on electrical and optical properties of GaAs1-xBix alloys are investigated. The n-type GaAs1-xBix layers, having from 0% to 2.3% Bi, were grown by molecular beam epitaxy on n + -GaAs at substrate temperature of 378 °C and subsequently annealed at a temperature of 700 °C. Deep level transient spectroscopy (DLTS) revealed distinct evolution of deep electron traps and their properties upon annealing. It is shown that annealing distinctly influences both the free electron concentration and the total trap concentration in the GaAsBi layers having increasing Bi content. Moreover, annealing also influences the low temperature photoluminescence (PL) spectra, while little effect is observed in room temperature photoreflectance (PR) spectra, which probes the band gap. Distinguishing and identifying between GaAs host-defects and Bi-related defects is carried out using the GaAsBi band gap diagram, which correlates activation energies of deep level traps in the band gap, accounting for the Bi-induced band gap reduction. On the basis of this approach, we are able to identify the revealed electron traps and assign them to GaAs native defects and impurities or Bi-related ones.

DOI.org