Patent ID: 9672407
Date: 2017-06-06
CPC Classifications: G03F,G06K

Claim:
1. A fingerprint sensing device comprising: a sensing chip comprising an array of sensing elements, said sensing elements being configured to be connected to readout circuitry for detecting a capacitive coupling between each of said sensing elements and a finger placed on a sensing surface of said sensing device, wherein a surface of said sensing elements define a sensing plane; a plurality of interposer structures arranged on said sensing chip extending above said sensing plane, wherein said plurality of interposer structures have the same height above said sensing plane, wherein said plurality of interposer structures are arranged in alignment with boundaries between said sensing elements, such that a central portion of each sensing element is not covered by an interposer structure; and a protective plate attached to said sensing chip by means of an adhesive arranged on said sensing chip, wherein said protective plate rests on said interposer structures such that a distance between said protective plate and said sensing plane is defined by the height of said interposer structures, wherein said plurality of interposer structures are formed of a material having a dielectric constant lower than a dielectric constant of said adhesive.