Patent ID: 6900644

Claim:
A capacitive fingerprint sensor against ESD damage and contamination interference, comprising: a silicon substrate having integrated circuits; a plurality of plate electrodes arranged on the substrate in a form of an array; a metal mesh crisscrossing between the plate electrodes and being flush with the plate electrodes, the metal mesh surrounding each of the plate electrodes and being connected to a ground; a plurality of ESD units connected to the metal mesh, each of the ESD units being formed between a predetermined number of adjacent plate electrodes in the plate electrodes, and the number of the ESD units being less than that of the plate electrodes; a plurality of bonding pads serving as input and output portions for the capacitive fingerprint sensor; and a protection layer completely covering the plate electrodes and the metal mesh and partially covering the ESD units and the bonding pads so as to form a plurality of first openings on the ESD units and a plurality of second openings on the bonding pads, a dimension of each of the first openings being smaller than that of each of the second openings, the plate electrodes comprising a plurality of sacrificial electrodes and a plurality of standard electrodes, the sacrificial electrodes being adjacent to the ESD units, a dimension of each of the sacrificial electrodes being smaller than that of each of the standard electrodes.