Impact of substrate -target distance on the hemispherical expansion plume generated by the deposit of SnSe nanoparticle thin films
Abstract
The PLD technique is used to develop SnSe thin films on quartz substrates using a Nd: YAG pulsed laser at a deposition temperature of (573 K) with varied substrate-target distances (2,2.5,3, and 3.5) cm. The produced thin films are characterized using XRD, which reveals an orthorhombic structure with a polycrystalline system. Using transmittance spectra to calculate the energy band gap, which ranges from (1.71-3.65) eV. Absorption coefficient, refractive index, loss factor (loss tangent), extinction coefficient, and optical conductivity are affected by substrate-target distance Ds-t) change. The dislocation density and particle size are changed by the Ds-t change, too. FESEM shows the film morphology and reveals the formation of two structures: a pop-corn like structure and nanorods.