Color image sensor and method for fabricating the same

A method for fabricating a color image sensor for scanning and converting an optical image into electrical signals, comprising the steps of:

• (a) forming a first conductive type semiconductor layer on a substrate;
• (b) forming field oxide layers on the first conductive type semiconductor layer to define regions for red, green and blue photodiodes;
• (c) providing an ion implantation mask having different mask patterns for the red, the green and the blue photodiodes;
• (d) implanting impurity ions into the first conductive type semiconductor layer through the use of said ion implantation mask to form second conductive type diffusion regions in the first conductive type semiconductor layer;
• and
• (e) applying a thermal process to the resulting structure to form different first, second and third depletion regions corresponding to the red, the green and the blue photodiodes, respectively, wherein the second depletion region is more adjacent to the surface of the semiconductor layer than the first depletion region and the third depletion region is more adjacent to the surface of the semiconductor layer than the second depletion region.