Influence of thickness on the structure, electrical, optical and electrochromic properties of AZO thin films and their inorganic all-solid-state devices

Abstract

Aluminized zinc oxide (AZO) thin films with different thickness were deposited and their electrical and optical properties of the studied films were measured. The results of XRD patterns and SEM measurement images verified that the micromorphology of the films correlated with the thickness. Meanwhile, it was demonstrated that the AZO films with the thickness of about 657 nm showed excellent balance between the electrical properties and optical properties. The highest value of ΦTC is 12.14 × 10−3 Ω−1 for the thin films with the thickness of 657 nm, which exhibited the lowest Rs of 36.67 Ω/□ and an effective average transmittance of 92.2%. The NiOx and WO3 thin films were fabricated on as-deposited AZO films, respectively. The investigations of electrochemical properties of NiOx and WO3 thin films suggested that AZO films prepared in 3.5 h with the thickness of 657 nm demonstrated the optimal performance when they served as the transparent electrode. Furthermore, in-situ spectro-electrochemistry studies of electrochromic devices, using 657 nm AZO films as the outer electrode, presented a long-term durability, high coloration efficiency (46.64 cm2 C−1) and bleaching efficiency (58.79 cm2 C−1).