Insights into spray-coated p-type Li-doped ZnO thin films: An examination of structural, chemical, optical, and electrical characteristics

This study focused on synthesizing ZnO thin films with lithium doping using a spray pyrolysis technique. We conducted a comprehensive analysis of their structural, optical, and electrical properties through techniques such as XRD, UV–visible spectroscopy, atom probe tomography (ATP), and Hall four-point probe. The XRD results indicated a polycrystalline structure with a wurtzite hexagonal pattern. Notably, increased Li doping concentration enhanced crystallinity while slightly reducing crystallite size, revealing nuanced effects on film microstructure. ATP demonstrated a remarkably homogeneous distribution of chemical elements within the Li-doped ZnO sample. The films, approximately 650 nm thick, exhibited high optical transmittance, surpassing 60% in the visible region at 550 nm wavelength, with optical band gap values ranging from 3.15 to 3.22 eV. Electrical property analysis revealed p-type conductivity, with the 6% Li-doped film displaying optimal characteristics: resistivity of 8.97 Ω cm, carrier concentration of 2.09 × 10 19 cm −3 , and Hall mobility of 3.32 cm 2 /V s. Graphical abstract