A nanoscale characterisation of extended defects in glassy-like As2Se3 semiconductors with PAL technique

• Published in: Physica. B, Condensed matter Vol. 340-342; pp. 960 - 964
• Main Authors: Shpotyuk, O., Kovalskiy, A., Filipecki, J., Hyla, M., Kozdras, A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 31-12-2003
• Subjects: Extended defects; Glass; Positron annihilation; Extended defects; Glass; Positron annihilation
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2003.09.173

A meaningful interpretation of positron lifetime characteristics for glassy-like g-As2Se3 is developed taking into account calculations of Jensen et al. (J. Non-Cryst. Solids 170 (1994) 57) for positrons trapped by free-volume extended defects in orthorhombic As2Se3 and void volume distribution for 146-atoms layer-biased model of amorphous As2Se3 presented by Popescu (J. Non-Cryst. Solids 35–36 (1980) 549). The obtained results are compared for samples having different thermal pre-history. Two groups of experimental results with close lifetime characteristics are distinguished for each of the investigated samples. This feature is explained in terms of average positron lifetime by applying two-state positron trapping model for mathematical treatment of the obtained spectra.