Patent ID: 6815787
Filing Date: 2004-11-09
Classification: H01L

Abstract:
A new grid metal design for image sensors comprising:a semiconductor image sensor chip having a pixel region covering most of the chip and a logic circuit region on the chip periphery, the pixel region containing an array of image pixels where for each image pixel the majority of its area is occupied by a light sensing element and the other image pixel circuit elements are arranged in the periphery of the image pixel without overlapping the image sensing element; a number of metal levels of the first type, where at each of the levels of the first type functional patterns exist both for the chip peripheral logic circuits and for the pixel circuit elements; a number of metal levels of the second type, where in each of said levels of the second type functional patterns may exist only for the chip peripheral logic circuits and dummy metal patterns cover the pixel region except for the light sensing elements, where the total number of metal levels is at least five and there is at least one level of type one and at least one level of type two; a first dielectric layer under the first metal layer, an interlevel dielectric layer between said metal levels of either type and a passivation layer over the last metal level.