Some insights into the mechanism of photoluminescence of As-S-based films synthesized by PECVD

Chalcogenide arsenic sulphide thin films were obtained by reacting arsenic and sulfur vapors in a low-temperature plasma discharge. Photoluminescence (PL) of As-S films with compositions As34S66 and As53S47 is studied in detail. An increase in the arsenic concentration leads to the emergence of a cr...
Ausführliche Beschreibung

Chalcogenide arsenic sulphide thin films were obtained by reacting arsenic and sulfur vapors in a low-temperature plasma discharge. Photoluminescence (PL) of As-S films with compositions As34S66 and As53S47 is studied in detail. An increase in the arsenic concentration leads to the emergence of a crystalline phase in the As53S47 films. In addition, these films exhibit an intense broad PL band with a maximum at 2.2 eV upon a continuous 473 nm laser excitation. The interplay between composition, structure and optical properties is revealed. By coupling of PL, Raman spectroscopy and absorption data, possible mechanisms of radiative recombination in the context of the glass structure formation in the plasma discharge are discussed. Ausführliche Beschreibung