Wave guide filter for semiconductor imaging devices

In some embodiments, an image sensor is provided. The image sensor includes a photodetector disposed in a semiconductor substrate. A wave guide filter having a substantially planar upper surface is disposed over the photodetector. The wave guide filter includes a light filter disposed in a light filter grid structure. The light filter includes a first material that is translucent and has a first refractive index. The light filter grid structure includes a second material that is translucent and has a second refractive index less than the first refractive index.