Development of ZnO-based transparent conductive coatings

We have developed a range of single and multilayer transparent conducting coatings consisting of three to five alternating layers of Al-doped ZnO (AZO) and metals using E-beam evaporation method. The prepared optimized coatings show excellent optical and electrical properties, improved thermal and long-term stability. Optimum thickness of metal and AZO layers was determined for high optical transmittance and good electrical conductivity. X-ray diffraction, spectrophotometer, atomic-force microscopy, scanning electron microscopy and four-point probe were used to explore the possible changes in electrical and optical properties. It was found that the multilayer coatings consisting of Al-doped ZnO and Ag metal show satisfactory properties of low resistance of 5 Ω/sq, high transmittance of 90% and thermal stability up to 500 °C.