SOLID STATE IMAGE PICKUP DEVICE AND SOLID STATE IMAGE PICKUP DEVICE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a solid state image pickup device and a solid state image pickup device manufacturing method which can simplify a manufacturing process.SOLUTION: A solid state image pickup device according to an embodiment comprises a plurality of photoelectric conversion elements, a field effect transistor, trenches and a P-type impurity diffusion region. The plurality of photoelectric conversion elements are arranged two-dimensionally in a semiconductor layer. The field effect transistor has N-type source and drain on a surface side of the semiconductor layer. The trenches pierce the semiconductor layer from a surface to a rear face to surround respective photoelectric conversion element and each of which has a width increasing with the increasing distance from the surface of the semiconductor layer toward a position at a predetermined depth and not increasing at a position deeper than the position at the predetermined depth. The P-type impurity diffusion region is provided in a lateral face of the trench and has a P-type impurity concentration at a portion of the semiconductor layer from the surface to the position at the predetermined depth is lower than a P-type impurity concentration at a portion deeper than the position at the predetermined depth.SELECTED DRAWING: Figure 3