Gas sensor and method of making

Abstract

A gas sensor is disclosed. The gas sensor includes a gas sensing layer, at least one electrode, an adhesion layer, and a response modification layer adjacent to said gas sensing layer and said layer of adhesion. A system having an exhaust system and a gas sensor is also disclosed. A method of fabricating the gas sensor is also disclosed.

What is claimed as new and desired to be protected by Letters Patent of the United States is: 
     
         1 . A gas sensor, comprising:
 a gas sensing layer;   at least one electrode;   an adhesion layer; and   a response modification layer adjacent to said gas sensing layer and said layer of adhesion.   
     
     
         2 . The gas sensor of  claim 1 , wherein
 said gas sensing layer comprises at least one chemical composition with a chemical formula L α M β O γ  and a dopant,   wherein L is at least one element selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, V, Cu, Zr, Hf, Al, Si, P, Tb, and combinations thereof:   wherein M is at least one element selected from the group consisting of Ti, Mn, Fe, Co, Ni, Zn, Y, Nb, Mo, Ru, La, Ta, W, Ga, In, Sn, Sb, Bi, Ce, Sm, Gd, and combinations thereof; and   wherein, α, β, γ, are self-consistent.   
     
     
         3 . The gas sensor of  claim 2 , wherein incorporated into the gas sensing layer is at least one dopant selected from the list consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, V, Cu, Zr, Hf, Al, Si, P, Tb, Ti, Mn, Fe, Co, Ni, Zn, Y, Nb, Mo, Ru, Rh, Pd, La, Ta, W, Ga, In, Sb, Bi, Ce, Sm, Gd, Cd, Re, Pt, Ge, Cr, Pb, Lu, Nd, Pr, Eu, and combinations thereof. 
     
     
         4 . The gas sensor of  claim 2 , wherein α>0 only when β>0, and a≦β. 
     
     
         5 . The gas sensor of  claim 1 , wherein the said at least one electrode is positioned within the adhesion layer. 
     
     
         6 . The gas sensor of  claim 1 , wherein said adhesion layer comprises at least one chemical element selected from the group Ti, Cr, and combinations thereof. 
     
     
         7 . The gas sensor of  claim 1 , wherein said response modification layer comprises at least one chemical element selected from the group Mg, V, Cu, Zr, Hf, Al, Si. Ti, Mn, Fe, Co, Ni, Zn, Nb, Mo, Ru, Rh, Pd, La, Ta, W, In, Sn, Sb, Bi, Sm, Re, Pt, Gc, Cr, and combinations thereof. 
     
     
         8 . The gas sensor of  claim 1 , wherein said gas sensing layer is capable of detecting at least one analyte selected from the group consisting of NO, NO 2 , SO x , O 2 , H 2 O, NH 3 , CO, and combinations thereof. 
     
     
         9 . The gas sensor of  claim 1 , comprising:
 a substrate layer;   a heating layer adjacent to the substrate layer;   a first glass layer adjacent to the heating layer;   a temperature sensing layer adjacent to the first glass layer; and   a second glass layer between the temperature sensing layer and the adhesion layer.   
     
     
         10 . The gas sensor of  claim 1 , wherein said gas sensing layer is configured for equisensitive response towards two analytes selected from the group consisting of NO, NO 2 , SO x , O 2 , H 2 O, NH 3 , CO, and combinations thereof. 
     
     
         11 . The sensor of  claim 1 , comprising a catalyst layer that aids in the conversion of one or more analyte species to one or more different analyte species. 
     
     
         12 . The gas sensor of  claim 1 , wherein a gas species filter material is disposed adjacent to a gas sensing surface of said gas sensing layer. 
     
     
         13 . The gas sensor of  claim 1 , wherein the at least one electrode is placed in a sandwich geometry, a side-by-side geometry, an interdigitated geometry, a parallel geometry, or combinations thereof. 
     
     
         14 . The gas sensor of  claim 1 , wherein said gas sensor is arranged in a flip-chip arrangement. 
     
     
         15 . The gas sensor of  claim 1 , wherein a response of the sensor is measured using an AC detection technique, a DC detection technique, or a combination thereof. 
     
     
         16 . The gas sensor of  claim 1 , wherein the at least one electrode comprises at least two electrodes and an electrical resistance between the at least two electrodes is less than about 50 MΩ. 
     
     
         17 . A system, comprising:
 an exhaust system to transport gases; and   a gas sensor, comprising:   a gas sensing layer;   at least one electrode;   an adhesion layer; and   a response modification layer adjacent to said gas sensing layer and said layer of adhesion.   
     
     
         18 . The system of  claim 17 , wherein
 said gas sensing layer comprises at least one chemical composition with a chemical formula L α M β O γ ,   wherein L is at least one element selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, V, Cu, Zr, Hf, Al, Si, P, Tb, and combinations thereof;   wherein M is at least one element selected from the group consisting of Ti, Mn, Fe, Co, Ni, Zn, Y, Nb, Mo, Ru, La, Ta, W, Ga, In, Sn, Sb, Bi, Ce, Sm, Gd and combinations thereof; and   wherein, α, β, γ, are self-consistent.   
     
     
         19 . The gas sensing layer of  claim 18 , wherein a>0 only when β>0, and α≦β. 
     
     
         20 . The system of  claim 17 , wherein the said system is a motorized vehicle. 
     
     
         21 - 36 . (canceled)