Structure and method of manufacture

Abstract

A structure for a chemical sensing device includes a plurality of recesses and a plurality of electrically conductive elements located in, and protruding from, the plurality of recesses.

1 - 20 . (canceled) 
     
     
         21 . A chemical sensing device, comprising:
 a pair of conductive elements supported by a support structure, each conductive element having a base embedded in the support structure and a protrusion protruding from the support structure; and   a sensing material on the support structure extending between and electrically connecting the protruding parts of the conductive elements, the sensing material having an electrical conductivity that changes upon exposure to an analyte.   
     
     
         22 . The device of  claim 21 , where the sensing material is disposed on a surface of the support structure that extends between the protruding parts of the conductive elements. 
     
     
         23 . The device of  claim 22 , where the support structure includes:
 a first part along the base of each conductive element; and   a second part on the first part at least partially surrounding the base of each conductive element and defining the surface of the support structure that extends between the protruding parts of the conductive elements.   
     
     
         24 . The device of  claim 23 , where the support structure includes an adhesive between the first part of the support structure and the base of each conductive element and between the first and second parts of the support structure. 
     
     
         25 . The device of  claim 21 , where:
 a width of the conductive element is constant from the base to the protrusion;   a length of the protrusion is 1 micro-meter to 100 micro-meters; and   a ratio of the length of the protrusion to the width of the conductive element is 0.2:1 to 20:1.   
     
     
         26 . The device of  claim 25 , where:
 a length of each conductive element is a sum of a length of the base and the length of the protrusion; and   a ratio of the length of each conductive element to the length of the base is 1.1:1 to 2:1.   
     
     
         27 . The device of  claim 21 , where the pair of conductive elements is a single pair of conductive elements. 
     
     
         28 . A chemical sensing device, comprising:
 an array of electrically conductive elements embedded in and protruding from a support structure; and   a chemically sensitive material on the support structure at least partially surrounding the protruding parts of the conductive elements.   
     
     
         29 . The device of  claim 28 , where the chemically sensitive material has an electrical conductivity that changes upon exposure to an analyte. 
     
     
         30 . The device of  claim 29 , where a porosity of the chemically sensitive material exceeds a percolation threshold of the analyte. 
     
     
         31 . The device of  claim 30 , where the chemically sensitive material is selected from the group consisting of a conductive organic polymer, inorganic nanoparticles coated with metal nanoparticles, inorganic nanoparticles coated with oxide nanoparticles, graphene, carbon nanotubes coated with metal nanoparticles, and carbon black. 
     
     
         32 . The device of  claim 28 , where the chemically sensitive material covers the conductive elements. 
     
     
         33 . A chemical sensing device, comprising:
 multiple conductive elements supported by a support structure, each conductive element having a base embedded in the support structure and a protrusion protruding from the support structure, the base being longer than the protrusion; and   a sensing material on a surface of the support structure electrically connecting the protruding parts of the conductive elements, the sensing material having a material property that changes upon exposure to an analyte.   
     
     
         34 . The device of  claim 33 , where the protrusion is 100 micro-meters or shorter. 
     
     
         35 . The device of  claim 33 , where the material property is electrical conductivity.