Methods for manufacturing sensors for sensing airborne contaminant of tobacco smoke

Abstract

A method for manufacturing a sensor for sensing an airborne contaminant of tobacco smoke includes forming interdigitated electrodes on a substrate and depositing, on the substrate above the two interdigitated electrodes a conductive polyaniline bulk film having resistance sensitive to binding of the airborne contaminant of tobacco smoke thereto, such that resistance of the conductive polyaniline bulk film is measurable using the interdigitated electrodes.

What is claimed is: 
     
         1 . A method for manufacturing a sensor for sensing an airborne contaminant of tobacco smoke, comprising:
 forming interdigitated electrodes on a substrate;   dissolving bulk polyaniline and the airborne contaminant of tobacco smoke in a protonating agent to form a partially protonated and conductive polyaniline solution;   depositing the partially protonated and conductive polyaniline solution on the substrate above the interdigitated electrodes to form a conductive polyaniline bulk film that is partially protonated; and   doping the conductive polyaniline bulk film with a secondary dopant to fully protonate the conductive polyaniline bulk film, so as to form the sensor.   
     
     
         2 . The method of  claim 1 , the step of dissolving comprising dissolving the bulk polyaniline and the airborne contaminant in a protonating agent that is at least 98% pure. 
     
     
         3 . The method of  claim 2 , the step of dissolving comprising dissolving the bulk polyaniline and the airborne contaminant in formic acid. 
     
     
         4 . The method of  claim 1 , the step of doping comprising doping the conductive polyaniline bulk film with HCl. 
     
     
         5 . The method of  claim 1 , the step of doping comprising dip-coating the conductive polyaniline bulk film in the secondary dopant. 
     
     
         6 . The method of  claim 1 , the step of depositing comprising spin-coating the partially protonated and conductive polyaniline bulk solution onto the substrate. 
     
     
         7 . The method of  claim 6 , the step of spin-coating comprising forming the conductive polyaniline bulk film with a thickness of approximately 100 nanometers. 
     
     
         8 . The method of  claim 1 , the step of forming interdigitated electrodes comprising forming two interdigitated electrodes separated apart by approximately 20 microns. 
     
     
         9 . The method of  claim 8 , the step of depositing comprising forming the conductive polyaniline bulk film with a thickness of approximately 100 nanometers. 
     
     
         10 . The method of  claim 1 , the airborne contaminant being nicotine. 
     
     
         11 . A method for manufacturing a sensor for sensing an airborne contaminant of tobacco smoke, comprising:
 forming two interdigitated electrodes on a substrate, the two interdigitated electrodes being separated apart by approximately 20 microns;   on the substrate above the two interdigitated electrodes, depositing a conductive polyaniline bulk film having resistance sensitive to binding of the airborne contaminant of tobacco smoke thereto, such that resistance of the conductive polyaniline bulk film is measurable using the two interdigitated electrodes.   
     
     
         12 . The method of  claim 11 , the step of depositing comprising producing the conductive polyaniline bulk film with thickness of approximately 100 nanometers. 
     
     
         13 . The method of  claim 12 , the step of depositing comprising spin-coating a conductive polyaniline solution onto the substrate above the two interdigitated electrodes. 
     
     
         14 . The method of  claim 11 , the step of depositing comprising forming each of the two interdigitated electrodes with finger width of approximately 40 microns. 
     
     
         15 . The method of  claim 14 , the step of depositing comprising producing the conductive polyaniline bulk film with thickness of approximately 100 nanometers. 
     
     
         16 . The method of  claim 15 , the step of forming comprising forming each of the two interdigitated electrodes with thickness of approximately 120 nanometers. 
     
     
         17 . The method of  claim 11 , the step of depositing comprising depositing a fully protonated conductive polyaniline bulk film on the substrate. 
     
     
         18 . The method of  claim 11 , in the step of depositing, the conductive polyaniline bulk film being molecularly imprinted with the airborne contaminant. 
     
     
         19 . The method of  claim 11 , the airborne contaminant being nicotine. 
     
     
         20 . The method of  claim 11 , further comprising measuring background resistance between the two interdigitated electrodes when the device is not exposed to the airborne contaminant.