Fingerprint Sensor and Interconnect

Abstract

Particular embodiments of the present invention are directed to a flexible fingerprint sensor interconnect apparatus that includes a fingerprint sensor chip having at least one die contact and a multilayer flexible substrate. Furthermore, the apparatus includes at least one conductive trace in the multilayer flexible substrate, and the at least one conductive trace has an exposed contact region that is directly electrically coupled to the at least one contact pad.

1 . A flexible fingerprint sensor interconnect apparatus, comprising: 
 a fingerprint sensor chip having at least one die contact;    a multilayer flexible substrate; and    at least one conductive trace in the multilayer flexible substrate, wherein the at least one conductive trace has an exposed contact region that is directly electrically coupled to the at least one contact pad.    
     
     
         2 . The apparatus of  claim 1 , wherein the exposed contact region is wire bonded to the at least one die contact.  
     
     
         3 . The apparatus of  claim 1 , wherein the exposed contact region is coupled to the at least one die contact using a ball/bump method.  
     
     
         4 . The apparatus of  claim 1 , wherein the exposed contact region is coupled to the at least one die contact using a tape automated bonding method.  
     
     
         5 . The apparatus of  claim 1 , further comprising an encapsulation material covering the exposed contact region and the die contact.  
     
     
         6 . The apparatus of  claim 5 , wherein the encapsulation material is a pre-molded package.  
     
     
         7 . The apparatus of  claim 5 , wherein the encapsulation material is transfer molded.  
     
     
         8 . The apparatus of  claim 1 , wherein the multilayer flexible substrate includes a second contact region that is configured to mate with a mating conductor.  
     
     
         9 . The apparatus of  claim 1 , wherein the multilayer flexible substrate includes a second contact region and a third contact region, wherein the second and third contact regions are configured to mate with corresponding mating connectors.  
     
     
         10 . A flexible fingerprint sensor interconnect apparatus, comprising: 
 a multilayer flexible substrate having conductive traces that lead to a connector at one end of the substrate for connecting the flexible fingerprint sensor interconnect apparatus to an external circuit;    a fingerprint sensor chip mounted on an end portion of the multilayer flexible substrate distal from the connector end, the fingerprint sensor chip having a sensor surface and sensor contacts, the sensor contacts electrically coupled to the conductive traces; and    a rigid molded package coupled to a portion of the bottom of the multilayer flexible substrate below the fingerprint sensor chip such that at least a portion of the multilayer flexible substrate is positioned between the fingerprint sensor and the molded package, such that an open top cavity exposing the sensor surface of the fingerprint sensor for access by a user is formed, and such that the portion of the fingerprint sensor interconnect apparatus proximate the molded package is rigid, and the portion of the fingerprint sensor interconnect apparatus distal from the molded package is flexible.    
     
     
         11 . The apparatus of  claim 10 , further comprising a stiffener coupled to the flexible substrate at the connector end thereof.  
     
     
         12 . The apparatus of  claim 10 , wherein: 
 the conductive traces are positioned internally within the multilayer flexible substrate;    a portion of the multilayer flexible substrate has an opening adjacent to the fingerprint sensor such that a portion of at least some of the conductive traces are exposed in the opening; and    the sensor contacts are electrically coupled to the conductive traces via connecting wires between the sensor contacts and the exposed portions of the conductive traces.    
     
     
         13 . The apparatus of  claim 12 , further comprising an encapsulation material disposed in the cavity covering the wires.  
     
     
         14 . A fingerprint sensing apparatus, comprising: 
 an elongate multilayer flexible substrate having a conductive layer having a plurality of conductive traces;    a fingerprint sensor mounted on top of the elongate multilayer flexible substrate proximate a first end thereof; the fingerprint sensor having a sensor surface and a plurality of electrical contacts, wherein the sensor electrical contacts are electrically coupled to one or more of the conductive traces in the conductive layer at a location removed from the first end;    a frame mounted below a portion of the elongate multilayer flexible substrate adjacent the first end, such that at least a portion of the elongate multilayer flexible substrate is between the frame and the sensor, and such that the sensor surface is exposed and the portion of the elongate multilayer flexible substrate proximate the frame is rigid; and    a connector disposed at a second end of the elongate multilayer flexible substrate distal from the first end, the connector having a plurality of electrical contacts coupled to the conductive traces.    
     
     
         15 . The apparatus of  claim 14 , further comprising a stiffener coupled proximate to the connector for providing rigidity to the connector.