The invention discloses an
image sensor and a manufacturing method thereof, and belongs to the technical field of semiconductors. The
image sensor comprises a substrate which is divided into a plurality of active regions by a
shallow trench isolation structure; the
photodiode, the charge storage region and the
floating diffusion region are arranged in the substrate at intervals; the global transmission grid is arranged between the
photodiode and the charge storage region and comprises a first
branch arranged on the active region and a second
branch arranged on the
shallow trench isolation structure; the transfer gate is arranged between the charge storage region and the
floating diffusion region and comprises a first gate arranged on the active region and a second gate arranged on the
shallow trench isolation structure; the first
mask layer is arranged on the global
transmission gate and the transfer gate, and the second
mask layer is arranged on the first
mask layer on the first
branch and the first gate; the shading structure covers the first subsection, the charge
storage area and part of the transfer grid
electrode. According to the
image sensor and the manufacturing method thereof, the parasitic
light response is improved, and the manufacturing yield is improved.