IMAGE SENSOR AND METHOD OF MANUFACTURING THE SAME

摘要

An image sensor and its manufacturing method are provided to reduce random noise by using a gate conductive layer comprised of an oxide without containing nitrogen. A photo diode(22) is formed under a surface of a substrate(20). A gate structure(29) is formed on a side of a substrate where the photo diode is formed. The gate structure has a gate dielectric(24) comprised of oxide without containing nitrogen and a gate conductive layer(26) formed on the gate dielectric. The photo diode includes a first photo diode(22a) where a first impurity is doped and a second photo diode(22b) where a second impurity is doped on a lower part from the substrate. The first photo diode is formed on a lower part from the substrate and the second photo diode is formed on a lower part from the first photo diode.