Method of fabricating image sensor and reworking method thereof

A method of fabricating an image sensor device is provided. First, a substrate comprising a pixel array region and a pad region is provided. A patterned metal layer and a first planarization layer having an opening exposing the patterned metal layer in the pad region are sequentially formed on the substrate. A color filter array is formed on the first planarization layer in the pixel array region. A second planarization layer is formed to cover the color filter array and filled into the opening. A plurality of microlens is formed above the color filter array on the second planarization layer. A capping layer is conformally formed on the microlens and the second planarization layer. An etching step is performed to remove the capping layer and the second planarization layer in the opening so as to expose the patterned metal layer in the pad region.