Patent ID: 8604405

Claim:
An image sensor device, comprising: a device substrate having a front side surface and a back side surface, the device substrate having a radiation-sensing region operable to sense radiation that has a corresponding wavelength, wherein the radiation first enters the device substrate from the backside surface of the device substrate; a dielectric structure disposed over the device substrate, the dielectric structure comprising a plurality of layers that include: a first layer formed over the front side surface of the device substrate, the first layer having a first refractive index and a first thickness that is a function of the first refractive index, wherein the first layer contains a first type of dielectric material; a second layer formed over the first layer, the second layer having a second refractive index and a second thickness that is a function of the second refractive index, wherein the second layer contains a second type of dielectric material different from the first type of dielectric material, wherein at least one of the first layer or the second layer has a uniform thickness; an interconnect structure disposed over the dielectric structure in a manner such that the dielectric structure is disposed between the device substrate and the interconnect structure, wherein the interconnect structure includes a plurality of interconnect layers, each interconnect layer containing one or more conductive elements; and a lens disposed over the back side surface of the device substrate, wherein the device substrate is disposed between the lens and the first layer.