fbpx Engineering the structural, optical and electrical properties of Selenium thin films via Ag nanosandwiching | ARAB AMERICAN UNIVERSITY
Contact information for Technical Support and Student Assistance ... Click here

Engineering the structural, optical and electrical properties of Selenium thin films via Ag nanosandwiching

Project Summary: 

In this proposal we target engineering the structural, optical and electrical properties of selenium thin films. The Se films which are prepared by the physical vapor deposition technique under vacuum pressure of 10-5  mbar in our laboratory are of amorphous nature.   They are also classified as insulators with optical band gap of 2.0 eV. The morphology, insulating character and light insensitivity makes these films useless in optoelectronic technology. Thus, here in this proposal we aim to improve the optoelectronic properties of the film via nanosandwiching technique. The Ag metal slabs with thicknesses   of 25, 50, 75 and 100 nm will be sandwiched between two 500 nm thick selenium layers. The films are to be deposited onto glass and metal substrates at substrate temperature of 300 K. The thickness of the metal layer is expected to attenuate the energy band gap and lower the electrical resistivity of Se films. The detailed structural analysis on these films will be investigated by means of X-ray diffraction and scanning electron microscopy. In addition, an in situ crystallization process will be monitored by the temperature dependence X-ray studies. The elemental mapping of the Se in the presence of Ag and the Ag distribution through the Se will be investigated via energy dispersive X-ray spectroscopy.  The enhancements in the lattice parameters, grain size, microstrain, dislocation density and stacking faults will be investigated as function of temperature in the temperature range of 300-460 K. In addition, the associated changes in the electrical resistivity as function of temperature before and after the crystallization processes in the same temperature range will be studied to determine the electrical resistivity variations with Ag content and temperature. Furthermore, some optoelectronic device tests like photo sensors will be carried out to suggest some applications of these films.