CMOS IMAGE SENSOR AND METHOD FOR FABRICATION THEREOF

摘要

A CMOS image sensor and a manufacturing method thereof are provided to improve characteristics of a photodiode by restraining the increase of a dark current using a heavily doped region under a transfer gate. A photodiode region and a transfer transistor region are defined on a first conductive type semiconductor substrate(161). A second conductive type doped region is formed in the substrate of the photodiode region. A transfer gate is formed on the substrate of the transfer transistor region via a gate insulating layer. A heavily doped region(159) of the first conductive type is formed in the substrate under the transfer gate.