公开(公告)号：US20210209324A1

公开(公告)日：2021-07-08

申请号：US17058943

申请日：2019-05-27

Applicant: Fingerprint Cards AB

Inventor： Karl LUNDAHL ,  Hanna NILSSON ,  Adam BENSON ,  Martin GRIP

IPC: G06K9/00 ,  A61B5/1172 ,  G01S15/89

Abstract: An acoustic biometric imaging system comprising: a transparent device member having a first face to be touched by a finger surface of a user, and a second face opposite the first face, the transparent device member having a first acoustic impedance; a first ultrasonic transducer acoustically coupled to the second face of the transparent device member in a first transducer region for receiving acoustic signals conducted by the transparent device member from a finger touch region laterally spaced apart from the first transducer region, the first ultrasonic transducer having a second acoustic impedance; and an opaque masking layer arranged between the transparent device member and the first ultrasonic transducer in the first transducer region, the opaque masking layer having a third acoustic impedance between the first acoustic impedance and the second acoustic impedance.

公开(公告)号：US20200279089A1

公开(公告)日：2020-09-03

申请号：US16645959

申请日：2018-09-17

Applicant: FINGERPRINT CARDS AB

Inventor： Karl LUNDAHL ,  Hanna NILSSON ,  Martin GRIP

IPC: G06K9/00 ,  H01L41/047 ,  H01L41/311 ,  B06B1/06

Abstract: A method of manufacturing ultrasonic transducer devices, comprising fabricating an ultrasonic transducer panel; and dividing the ultrasonic transducer panel into ultrasonic transducer devices. Fabricating the ultrasonic transducer panel includes: providing a first carrier; arranging a plurality of piezoelectric elements spaced apart on the first carrier; applying a dielectric material on the plurality of piezoelectric elements to embed each piezoelectric element in the plurality of piezoelectric elements in the dielectric material, thereby forming a piezoelectric element device layer on the first carrier; thinning the piezoelectric element device layer, resulting in an exposed first side of each piezoelectric element in the plurality of piezoelectric elements; forming a first electrode layer on the piezoelectric element device layer, the first electrode layer including a first transducer electrode on the exposed first side of each piezoelectric element in the piezoelectric element device layer; and separating the piezoelectric element device layer from the first carrier.

公开(公告)号：US20200210667A1

公开(公告)日：2020-07-02

申请号：US16623443

申请日：2018-08-21

Applicant: Fingerprint Cards AB

Inventor： Hanna NILSSON ,  Adam BENSON ,  Karl LUNDAHL

IPC: G06K9/00 ,  H01L27/01

Abstract: A method for manufacturing a fingerprint sensor device. The method comprises providing a fingerprint sensor chip, arranging the fingerprint sensor chip on a carrier, depositing a cover layer on the fingerprint sensor chip, the cover layer comprising a polarizable material; moving a top electrode into contact with a top surface of the cover layer; and applying a voltage between the top electrode and a bottom electrode located below the cover layer and comprised in a material stack between the bottom of the carrier and the cover layer, creating an electric field in the cover layer, thereby poling the cover layer such that a dielectric constant of the cover layer in a direction perpendicular to the sensing array is higher than a dielectric constant in a direction parallel to the sensing array, thereby forming a cover layer having an anisotropic dielectric constant.

公开(公告)号：US20170316247A1

公开(公告)日：2017-11-02

申请号：US15654798

申请日：2017-07-20

Applicant: Fingerprint Cards AB

Inventor： Karl LUNDAHL ,  Hanna NILSSON

IPC: G06K9/00

CPC classification number: G06K9/0002 ,  G06K9/00 ,  G06K9/00053 ,  G06K9/00087

Abstract: The invention relates to a fingerprint sensing device comprising a sensing chip comprising an array of capacitive sensing elements. The sensing device comprises a coating material arranged in a layer on top of the array of sensing elements and comprising a plurality of cavities filled with a dielectric material. The dielectric material comprises reduced graphene oxide. Locations of the cavities correspond to locations of the sensing elements such that a cross-section area of a cavity covers at least a portion of an area of a corresponding sensing element. A dielectric constant of the dielectric material is higher than a dielectric constant of the coating material. The invention also relates to a sensing device where the dielectric coating layer containing reduced graphene oxide comprises trenches corresponding to areas between the sensing pixels filled with a fill material, where the dielectric coating layer has a higher dielectric constant than the fill material.