Effects of Li concentration in the precursor solution on NiO thin films deposited using electrostatic spray deposition

Undoped and Li-added NiO thin films were deposited using electrostatic spray deposition (ESD) techniques. Initially, the NiO thin films displayed minimal contamination, predominantly C and H. The NiO thin films exhibited a flat surface morphology comprising grains of uniform size, approximately 20-30 nm in diameter, and reliable crystal growth, with a full width at half maximum of approximately 0.30 in X-ray diffraction analysis. Moreover, the NiO/ZnO diode demonstrated superior properties when a 5 at% Li concentration solution was incorporated. The rectification ratio reached approximately 2.3 × 10³ at ±1.0 V, with an ideality factor of 1.9. Additionally, the NiO/ZnO diodes exhibited remarkable photovoltaic properties even without detailed optimization. These findings underscore the potential of ESD in advancing semiconductor thin-film technology, thereby paving the way for more cost-effective and scalable production methods.