Influence of Sn doping on the structure, optical, and electrical properties of p-type cuprous iodide thin films

The effects of the tin (Sn) doping on the characteristics of p-type cuprous iodide (CuI) thin films prepared using successive ionic layer adsorption and reaction (SILAR) have been examined in detail. The doping concentration of the Sn subjected to change from 0 to weight 8%. X-ray diffraction (XRD) consequences established the γ-phase cubic structure along the preferred development orientation analogous to (111) XRD plane. The Williamson and Hall (W-H) analysis has been used to calculated influence of crystallite size and micro-strain on the peak expansion of doping with different doping levels. The field-emission scanning electron microscope (FESEM) revealed the surface morphological and the grain size variation declined by means of doping concentration and agglomerated at large doping percentage. The estimated energy bandgap for the of pure and doped thin films changes as of 2.42 to 2.65 eV with Sn doping concentration. The photoluminescence (PL) results the of pure and doped CuI thin films presented a strong, room-temperature PL at the energy about their optical bandgaps and the peak intensity reduced with growing the doping level. The Sn doping improves the electrical conductivity with charge mobility and in addition to carrier concentration in CuI thin films as inveterate by Hall analysis. It can be proposed that the obtained results of CuI thin films with Sn doping are appropriate for hole transport layer of perovskite solar cells.