BACK ILLUMINATED IMAGE SENSOR

摘要

A back illuminated image sensor is provided to reduce the reflectance of light that penetrates into a substrate and reaches an interface between the substrate and an interlayer dielectric by forming an anti-reflective layer between the substrate and the interlayer dielectric. A photodiode(52) is formed on a substrate(50'). A dielectric layer(56) is formed on a first surface of the substrate. A wire layer(58) is formed in the dielectric layer. An anti-reflective layer is disposed between the substrate and the dielectric layer. Plural color filters(60) are formed on a second surface of the substrate opposite to the first surface. A micro lens(62) is formed on the color filter. First material layers and second material layers, which have different refractive indexes, are laminated in turn to form the anti-reflective layer. The first material is a silicon oxide layer. The second material is a silicon nitride layer. A refractive index of the first material layer is less than that of the second material index.