Method of fabricating image sensor and reworking method thereof

A method of fabricating an image sensor, comprising:

• proving a substrate having a pixel array region and a pad region, and a photo sensing unit array formed in the substrate;
• forming a dielectric layer, a patterned metal layer and a first planarized layer from bottom to top in sequence on the substrate, the first planarized layer having an opening to expose the patterned metal layer above the pad region;
• forming a color filter array on the first planarized layer above the pixel array region;
• forming a second planarized layer to covering the color filter array and the first planarized layer, and be filled into the opening;
• forming a plurality of microlenses corresponding to the color filter array on the second planarized layer;
• forming a capping layer on the microlenses and the second planarized layer conformally;
• and
• performing an etching step to remove the capping layer and the second planarized layer in the opening and expose the patterned metal layer above the pad region, wherein the capping layer and the second planarized layer have aligned etched ends.