Compositional and Thickness Effects on the Optical Properties of Zinc €“Doped Selenium €“Antimony Thin Films

Authors

  • Austine A Mulama Department of Physics, University of Nairobi, 30197-00100, Nairobi Kenya Department of Physics and Materials Science, Maseno University, 333-40105, Maseno Kenya
  • Julius M Mwabora Department of Physics, University of Nairobi, 30197-00100, Nairobi Kenya
  • Andrew O Oduor Department of Physics and Materials Science, Maseno University, 333-40105, Maseno Kenya
  • Cosmas M Muiva Department of Physics, Botswana International University of Science and Technology, 00741, Botswana

Abstract

Chalcogenide system of antimony (Sb)-selenium (Se)-zinc (Zn) system is a promising semiconductor for phase change memory devices due to its thermal stability and low power consumption. The study investigated the effect of film thickness and zinc content on the optical properties of thermally evaporated Sb10Se90-xZnx (x = 0, 5, 10 & 15 at. %) thin films. It was found that transmittance (T~ 85-40%) and optical band gap energy (Eopt ~ 1.60 eV €“ 1.22 eV) decreased but absorption coefficient (α~0.840 €“2.031 104 cm €“1) increased with increase in zinc content. Furthermore, as the film thickness increased from 53 ± 5 nm to 286 ± 10 nm, transmittance decreased but band gap energy increased due to zinc defects and localized states in the Sb10Se90-xZnx system.

Keywords: Selenium, phase change memory, localized states

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Published

2018-12-31

Issue

Vol. 44 No. 4 (2018)

Section

Articles