Magnetron sputtering method for the preparation of Cu-ZrB₂ composite film and their optical properties

The exceptional thermal and chemical stability of zirconium diboride (ZrB₂) is attributed to its unique combination of ceramic and metallic properties. In this work, copper composited zirconium diboride (Cu-ZrB₂) composite film was prepared on Si (100) substrates with dual-target magnetron co-sputtering method. The introduction of metal (Cu) has been observed to adjust the free electron concentration in thin films, thereby optimizing their properties. When copper was sputtered at 3 W, the composite film exhibited superior performance, demonstrating the average reflectance of 90% within the wavelength range of 3–14 μm. Additionally, it showcased remarkably low infrared emissivity values at 3–5 and 8–14 μm, measuring 0.309 and 0.294 respectively. This experiment has demonstrated that ZrB₂-based composite films have great potentials in low infrared emissivity applications.