Biometric sensor and sensor panel, method for detecting biometric pattern using the same, and method for manufacturing the same

Abstract

A biometric sensor panel includes (a) a first flexible substrate, (b) a plurality of first electrodes formed on the first flexible substrate, the first electrodes being arranged in a first direction, (c) a semiconductor layer formed on the first electrodes, (d) a second flexible substrate, (e) a plurality of second electrodes formed on the second flexible substrate, the second electrodes being arranged in a second direction crossing the first direction, and (f) a pressure sensitive conductive layer formed on the second electrodes, wherein the first and second flexible substrates face each other such that the semiconductor layer is in contact with the pressure sensitive conductive layer.

1 . A biometric sensor panel, comprising:
 a first flexible substrate;   a plurality of first electrodes formed on the first flexible substrate, wherein the electrodes of the plurality of first electrodes have a long dimension and a short dimension with the long dimension of the electrodes of the plurality of first electrodes being generally aligned in a first direction;   a semiconductor layer over the plurality of first electrodes;   a second flexible substrate;   a plurality of second electrodes formed on the second flexible substrate, wherein the electrodes of the plurality of second electrodes have a long dimension and a short dimension with the long dimension of the electrodes of the plurality of second electrodes being generally aligned in a second direction, the second direction being at least partially orthogonal to the first direction; and   a pressure sensitive conductive layer formed on the plurality of second electrodes, wherein the first and second flexible substrates face each other such that the semiconductor layer is in contact with the pressure sensitive conductive layer.   
     
     
         2 . The biometric sensor panel of  claim 1 , further comprising a first insulation layer formed on the first flexible substrate between the electrodes of the first plurality of electrodes. 
     
     
         3 . The biometric sensor panel of  claim 1 , wherein the semiconductor layer is a patterned layer including a plurality of semiconductor strips or islands, each formed on a corresponding one of the plurality of first electrodes. 
     
     
         4 . The biometric sensor panel of  claim 1 , further comprising a second insulation layer formed between the second electrodes on the second flexible substrate. 
     
     
         5 . The biometric sensor panel of  claim 1 , wherein the second electrodes has a barrel roof shape protruding toward the pressure sensitive conductive layer. 
     
     
         6 . The biometric sensor panel of  claim 1 , further comprising bumps that protrude towards the pressure sensitive conductive layer, formed on the plurality of first electrodes, the plurality of second electrodes, or both. 
     
     
         7 . A biometric sensor panel, comprising:
 a first flexible substrate;   a plurality of first electrodes formed on the first flexible substrate, the first electrodes being arranged in a first direction;   a first insulation layer formed on the first electrodes over the first flexible substrate;   a plurality of first contact pads formed on the first insulation layer, the first contact pads aligned with the first electrodes and connected to corresponding ones of the first electrodes through vias formed in the first insulation layer;   a semiconductor layer formed on the first contact pads over the first insulation layer; a second flexible substrate;   a plurality of second electrodes formed on the second flexible substrate, the second electrodes being arranged in a second direction crossing the first direction;   a second insulation layer formed on the second electrodes over the second flexible substrate;   a plurality of second contact pads formed on the second insulation layer, the second contact pads aligned with the second electrodes and connected to corresponding ones of the second electrodes through vias formed in the second insulation layer; and   a pressure sensitive conductive layer, wherein the first and second flexible substrates face each other such that each of the first contact pads is aligned with a corresponding one of the second contact pads via the semiconductor layer and the pressure sensitive conductive layer sandwiched therebetween.   
     
     
         8 . The biometric sensor panel of  claim 7 , further comprising:
 a first anisotropic conductive film (“ACF”) formed on the pressure sensitive conductive layer connecting the semiconductor layer and the pressure sensitive conductive layer; and   a second anisotropic conductive film (“ACF”) formed on the pressure sensitive conductive layer connecting the second contact pads and the pressure sensitive conductive layer.   
     
     
         9 . The biometric sensor panel of  claim 7 , wherein each of the first and second contact pads is formed in a bump shape protruding toward the pressure sensitive conductive layer. 
     
     
         10 . The biometric sensor panel of  claim 7 , wherein a thickness of the first contact pads is greater than a thickness of the semiconductor layer such that each part of the semiconductor layer formed on the first contact pads is isolated from the remaining part of the semiconductor layer formed directly on the first insulation layer. 
     
     
         11 . (canceled) 
     
     
         12 . A biometric sensor panel, comprising:
 a first flexible substrate;   a plurality of first electrodes formed on the first flexible substrate, the first electrodes being arranged in a first direction;   a second flexible substrate;   a plurality of second electrodes formed on the second flexible substrate, the second electrodes being arranged in a second direction crossing the first direction; and   an intermediate layer provided between the first flexible substrate and the second flexible substrate, the first electrodes and the second electrodes facing each other via the intermediate layer, the intermediate layer including:   a) a diode array formed on the first electrodes, the diode array including a plurality of vertical diode elements provided at crossing portions of the first and second electrodes;   b) an anisotropic conductive film (ACF) formed on the diode array; and   c) a pressure sensitive conductive layer formed on the ACF, the pressure sensitive conductive layer allowing the second electrode to be electrically connected to a diode element of the diode array via the ACF if the second flexible substrate is depressed by a biometric pattern towards the first flexible substrate at the corresponding crossing portion.   
     
     
         13 . The biometric sensor panel of  claim 12 , wherein each of the diode elements includes one of a p-n junction, a p+-p-n-n junction and/or a Schottky diode. 
     
     
         14 . The biometric sensor panel of  claim 12 , further comprising an insulation layer provided between the ACF and the first flexible substrate so as to fill spaces between the diode elements. 
     
     
         15 . The biometric sensor panel of  claim 12 , further comprising a second ACF formed on the pressure sensitive conductive layer. 
     
     
         16 . The biometric sensor panel of  claim 12 , wherein each of the diode elements has a forward drop of less than 1.0 V at an operating current.