Structural and optical properties of nano-powder-based (Sb1-x Bi x )2Te3 thin films
Abstract
Sb2Te3-containing alloys can be employed for many applications, including in solar cells, thermoelectric devices, and phase-change devices. For the first time in the literature, Nano-powder-based samples of Bi-doped Sb2Te3 were used as sources to prepare the corresponding films. Such films were expected to show numerous interesting features such as solid-state operation, special scalability, low maintenance, and a long operating lifetime. The crystal structure of the synthesized powders and nano-powder films is studied and investigated in the present manuscript by means of x-ray diffraction, scanning electron microscopy and atomic force microscopy analysis. Better adhesion to the glass substrates is revealed for the films prepared in our work. High absorption in the visible region is observed, confirming potential applications in the field of recording devices. Optical studies confirmed direct and allowed transitions in both films with energy band gaps of 0.78-0.83 eV. Refractive index (n), and dielectric constants (ɛ r) and (ɛ i) are calculated and studied as a function of the wavelength.
- Publication:
-
Materials Research Express
- Pub Date:
- August 2017
- DOI:
- 10.1088/2053-1591/aa804d
- Bibcode:
- 2017MRE.....4h5029A