Antireflection coatings with FeSi2 layer: Application to low-reflectivity wire grid polarizers

作者：Suzuki Motofumi^*; Takada Akio; Yamada Takatoshi; Hayasaka Takashi; Sasaki Kouji; Takahashi Eiji; Kumagai Seiji

来源：Thin Solid Films, 2011, 519(24): 8485-8489.

DOI：10.1016/j.tsf.2011.05.023

• Wire grid polarizers
• FeSi2
• Glancing angle deposition
• Antireflection

We theoretically propose two types of antireflection (AR) coatings for metals. One type consists of a single layer of a dielectric material having a high refractive index and is used for metals such as stainless steels in the infrared region. The other type consists of bilayers of absorptive and dielectric materials that are used in order to reduce the reflectance of high reflectivity metals such as Al in the visible region. In both types of AR coatings, FeSi2 plays an essential role. The bilayered AR concept has been applied to reduce the reflectance of wire grid (WG) polarizers made of Al. An FeSi2 layer, which serves as an absorptive layer, has been deposited by glancing angle deposition technique immediately on the top of Al wires covered with a thin SiO2 layer, which serves as a gap layer. For the optimum combination of the thicknesses of FeSi2 and SiO2, the reflectance reduces to lower than a few percent independent of the polarization, whereas the transmission polarization properties remain favorable. Because low reflectivity WG polarizers are completely composed of inorganic materials, they are useful for applications requiring thermal durability, such as liquid crystal projection displays.

• 出版日期2011-10-3