Electrodes for biosensors

Abstract

The present disclosure relates to an electrode for measuring an analyte. The electrode includes a first base layer, a first electrode layer upon the first base layer, and a second base layer. The first electrode layer is arranged between the first base layer and the second base layer. The first base layer includes a conductive metal, a conductive metal alloy, or carbon. The first electrode layer includes ruthenium metal, a ruthenium based metal alloy, nickel metal, or a nickel based metal alloy. The first base layer is made of different elements than the first electrode layer. The first base layer is more conductive than the first electrode layer.

1 . A method for forming a sensor for measuring an analyte, comprising:
 forming a first electrode on a substrate, wherein forming the first electrode comprises: 
 forming a first base layer on the substrate, the first base layer comprising a conductive metal, a conductive metal alloy, or carbon; and 
 forming a first electrode layer on the first base layer, the first electrode layer comprising ruthenium metal, a ruthenium based metal alloy, nickel metal, or a nickel based metal alloy, wherein the first base layer comprises different elements than the first electrode layer; and 
 forming a second base layer on the first electrode layer. 
   
     
     
         2 . The method of  claim 1 , wherein the first base layer is formed from a plurality of sublayers. 
     
     
         3 . The method of  claim 1 , wherein the first base layer comprises diamondlike carbon. 
     
     
         4 . The method of  claim 1 , further comprising:
 forming a second electrode on the substrate, wherein forming the second electrode comprises: 
 forming a second multi-layer stack on the substrate; and 
 forming a reagent layer on the second multi-layer stack, 
   wherein the first base layer, the first electrode layer, and the second base layer together form a first multi-layer stack, and wherein the second multi-layer stack of the second electrode has a same structure as the first multi-layer stack of the first electrode.   
     
     
         5 . The method of  claim 1 , further comprising:
 forming reaction chamber in the substrate that is in contact with the first electrode.   
     
     
         6 . The method of  claim 1 , further comprising:
 patterning the first base layer, the first electrode layer, and the second base layer to form a first multi-layer stack and a second multi-layer stack, wherein the first multi-layer stack forms the first electrode; and   forming a second electrode by forming a reagent layer on the second multi-layer stack.   
     
     
         7 . The method of  claim 6 , further comprising:
 connecting the first and second electrodes to a measuring device, wherein the measuring device is configured to apply a biasing potential signal through the first and second electrodes when a fluid comprising the analyte is exposed to the first and second electrodes.   
     
     
         8 . A method for forming a sensor for measuring an analyte, comprising:
 forming a first electrode on a substrate, wherein forming the first electrode comprises: 
 forming a first electrode layer on a substrate; 
 forming a first base layer on the first electrode layer, the first base layer comprising a conductive metal or a conductive metal alloy, or carbon; and 
 forming a second electrode layer on the first base layer, the second electrode layer comprising ruthenium metal, a ruthenium based metal alloy, nickel metal, or a nickel based metal alloy. 
   
     
     
         9 . The method of  claim 8 , wherein the first base layer comprises different elements than the first electrode layer. 
     
     
         10 . The method of  claim 8 , wherein the first base layer is formed from a plurality of sublayers. 
     
     
         11 . The method of  claim 8 , further comprising:
 forming a second electrode on the substrate, wherein forming the second electrode comprises: 
 forming a third electrode layer on the substrate; 
 forming a second base layer on the third electrode layer; 
 forming a fourth electrode layer on the second base layer; and 
 forming a reagent layer on the fourth electrode layer such that the second electrode operates as a working electrode, and wherein the first electrode operates as a reference electrode. 
   
     
     
         12 . The method of  claim 11 , wherein the third electrode layer comprises the same material and structure as the first electrode layer, wherein the second base layer comprises the same material and structure as the first base layer, and wherein the fourth electrode layer comprises the same material and structure as the second electrode layer. 
     
     
         13 . The method of  claim 12 , further comprising:
 forming reaction chamber in the substrate that is in fluid contact with the working electrode.   
     
     
         14 . The method of  claim 12 , further comprising:
 connecting the working and reference electrodes to a measuring device, wherein the measuring device is configured to apply a biasing potential signal through the working and reference electrodes when a fluid comprising the analyte is exposed to the first and second electrodes.   
     
     
         15 . A method for measuring an analyte in a fluid sample comprising:
 providing a sensor configured to receive and measure a concentration of the analyte based on a reduction/oxidation reaction of the analyte at a working electrode of the sensor;   applying the fluid sample to a reaction chamber of the sensor, the reaction chamber being fluidly coupled to the working electrode and a reference electrode; and   receiving a signal output from the sensor indicating the concentration of the analyte,   wherein the reference electrode is formed from a first multi-layer stack comprising a first base layer and a first electrode layer, wherein the first base layer comprises a conductive metal, a conductive metal alloy, or carbon, and   wherein the working electrode comprises a reagent layer arranged on a second multi-layer stack, the second multi-layer stack having a same structure as the first multi-layer stack.   
     
     
         16 . The method of  claim 15 , wherein the first electrode layer is made from different materials than the first base layer. 
     
     
         17 . The method of  claim 15 , wherein the first base layer has a higher electrical conductivity than the first electrode layer. 
     
     
         18 . The method of  claim 15 , wherein the first and second multi-layer stacks are arranged on a same substrate. 
     
     
         19 . The method of  claim 15 , wherein the signal output from the sensor is based on a biasing potential signal applied to the working electrode and the reference electrode as the reduction/oxidation reaction occurs at the working electrode. 
     
     
         20 . The method of  claim 15 , wherein the first multi-layer stack and the second multi-layer stack are formed by:
 forming the first base layer and the first electrode layer on a substrate; and   removing a portion of the first base layer and the first electrode layer from the substrate such that the first multi-layer stack and the second multi-layer stack are spaced apart from one another on the substrate and are formed from the same first base layer and the first electrode layer.