Introduction of Alumina and Silica Film Materials

Most oxide materials have many similar properties. The common oxide materials such as aluminum oxide and silicon dioxide are characterized by high temperature resistance, thermal shock resistance, high mechanical strength and rigidity.

Aluminum oxide is widely used as a high refractive index material in multilayer dielectric films. Aluminum oxide thin films have attracted great interest because of their excellent optical properties, high mechanical strength and hardness, good transparency and insulation, wear resistance, corrosion resistance and chemical inertia and have been widely used in the optical field. The optical properties of the films strongly depend on other factors such as coating conditions and impurity contamination. In the coating process, it is often used as the last protective layer because of its own stability.

Aluminum oxide film is an attractive material for optical fiber doping, because alumina has no absorption peak in visible and near infrared regions. Erbium-doped fiber amplifier (EDFA) has the characteristics of high gain, low noise, wide frequency bandwidth and high saturated output power at the lowest energy consumption wavelength of 1.55um in quartz-mode fiber. Therefore, EDFA is used as relay amplifier, power amplifier and preamplifier in optical communication and is the core component to realize all-optical transmission.

Silicon Dioxide is the only low refractive index oxide with a refractive index of 1.46.As an important nano-film material, silicon dioxide thin film has many advantages, such as wide transparent zone (0.15-8 um), high hardness, low thermal expansion coefficient, friction resistance, acid-base resistance, corrosion resistance, etc. It is widely used in optical thin film components, semiconductor integrated circuits, electronic devices, sensors, lasers, chemical catalysis, biomedicine, surface modification and pharmaceutical packaging.