1. Technical Field
The present invention relates to semiconductor structures, and more particularly, to semiconductor optical sensor structures having capability of collecting photons at different depths.
2. Related Art
Photons of different wave lengths after entering a semiconductor substrate will go down to different depths in the semiconductor substrate. Therefore, there is a need for a semiconductor optical sensor structure (and a method for forming the same) that can collect photons at different depths in the semiconductor substrate.
USPTO Backgrounds
USPTO Backgrounds