| abstract |
A capacitive sensing array device, particularly a fingerprint sensing array device, includes an array of sense electrodes covered by a layer of dielectric material defining a sensing surface over which, for example, a person's finger is placed in use. Grounding conductors are provided adjacent the sensing surface and extending alongside one or more edges of the sense electrodes. The material of the dielectric layer in the region of the grounding conductors at least has a non-linear I-V characteristic whereby electrostatic charges occurring in the device structure are conducted through this material to the grounding conductors. The grounding conductors may be buried in the dielectric layer and second electrodes provided on the sensing surface overlying respective sense electrodes and overlapping the grounding conductors. |