Structures for enhancement of local electric field, light absorption, light radiation, material detection and methods for making and using of the same

Abstract

Microstructures and nanostructures (100) consisting of a substrate (110), an array of pillars (120) capped by metallic disc (130), metallic dots (clusters or granules) (140) disposed on the sidewalls of the pillars, and a metallic backplane (150) that can interact to enhance a local electric field, the absorption of the light, and the radiation of the light are disclosed. Methods to fabricate the structures (100) are also disclosed. Applications of the structures to enhance the optical signals in the detection of molecules and other materials on a structure surface, such as fluorescence, photoluminescence and surface enhanced Raman Scattering (SERS) are also disclosed

1 . A method for enhancing detection of a property of a substance, utilizing a enhancement structure ( 100 ), comprising:
 placing the substance in proximity to, or in contact with said enhancement structure ( 100 );   illuminating said substance and/or said enhancement structure ( 100 ) with light;   detecting light radiated from said substance; and   wherein said enhancement structure ( 100 ) consists of
 a substrate ( 110 ); 
 at least one nanoscale pillar ( 120 ) extending from a surface of said substrate ( 110 ); 
 a nanoscale metallic disc ( 130 ) on top of each said pillar ( 120 ); 
 a metallic back plane ( 150 ) at a foot of each said pillar, said metallic back plane covering a substantial portion of said substrate surface; and 
 at least one nanoscale metallic dot structure ( 140 ) on an external vertical surface ( 120   s ) of each said pillar. 
   
     
     
         2 . The method of  claim 1  wherein said substance is disposed on said enhancement structure ( 100 ) in said placing step. 
     
     
         3 . The method of  claim 1  wherein said substance consists of a single molecule. 
     
     
         4 . The method of  claim 1  wherein said property is an optical property. 
     
     
         5 . The method of  claim 1  wherein said property includes at least one of a fluorescence optical signal, a photoluminescense optical signal, and a Surface Enhances Raman Scattering (SERS) optical signal. 
     
     
         6 . The method of  claim 1  further including the step of selecting one or more features of said enhancement structure ( 100 ) responsive to said property to be detected, said features including material selection, nanoscale pillar height, nanoscale pillar sidewall shape, nanoscale metallic disc shape, nanoscale metallic dot structure spacing ( 140   a ,  140   b ), metallic materials, and metallic backplane configuration. 
     
     
         7 . The method of  claim 6  wherein selecting said nanoscale metallic dot structure spacing includes selecting a gap distance ( 140   b ) between adjacent nanoscale metallic dot structures and/or selecting a gap spacing ( 140   a ) between said nanoscale metallic disc and adjacent nanoscale metallic dot structures. 
     
     
         8 . The method of  claim 1  wherein said step of detecting light detects optical signals associated with the detection of molecules or other materials on a surface of said substance, said optical signals selected from a set of optical signals including a fluorescence optical signal, a photoluminescense optical signal, and a Surface Enhances Raman Scattering (SERS) optical signal. 
     
     
         9 . The method of  claim 1  wherein said detected light is an optical signal comprising light generated near said surface of the substance or incoming to said surface of the substance, having a wavelength in the range from 10 nm to 30 microns. 
     
     
         10 . The method of  claim 1  wherein said detected light is an optical signal comprising light generated near or incoming to said surface of the substance or said enhancement structure ( 100 ) having a wavelength which is substantially near a resonant peak wavelength of said nanoscale pillar ( 120 ) and nanoscale metallic disc ( 130 ) structures. 
     
     
         11 . A nanoscale structure ( 100 ) that enhances, at a material, a local electric field induced by incoming light, absorption of light, or the radiation of light generated at the surface of the material, comprising:
 a substrate ( 110 );   at least one pillar ( 120 ) extending from a surface of the substrate;   a metallic disc ( 130 ) disposed on a top of each pillar;   a metallic back plane ( 150 ) at a foot of each pillar, said metallic back plane covering a substantial portion of the substrate surface; and   at least one metallic dot structure ( 140 ) disposed on an external vertical surface ( 120   s ) of each pillar.   
     
     
         12 . The nanoscale structure of  claim 11  wherein said substrate ( 110 ) is an electrical insulator. 
     
     
         13 . The nanoscale structure of  claim 11  wherein said substrate ( 110 ) is a dielectric insulator. 
     
     
         14 . The nanoscale structure of  claim 11  wherein said substrate ( 110 ) is a semiconductor. 
     
     
         15 . The nanoscale structure of  claim 11  wherein said substrate ( 110 ) is a laminate structure, and wherein a layer ( 120   a ) at said surface of the substrate ( 110 ) is either an electrical insulator or a semiconductor; and wherein a body of said substrate below said layer at said surface is any solid material. 
     
     
         16 . The nanoscale structure of  claim 11  wherein the top of said at least one pillar ( 120 ) has a shape selected from the group of shapes consisting of round, pointed, polygonal, pyramidal, elliptical, elongated bar shaped, or any combinations thereof. 
     
     
         17 . The nanoscale structure of  claim 11  wherein said at least one pillar ( 120 ) has a sidewall surface ( 120   s ) that is columnar, sloped, or curved. 
     
     
         18 . The nanoscale structure of  claim 11  wherein said at least one pillar ( 120 ) has a height in the range from 5 nm to 7000 nm and a diameter in the range from 5 nm to 8000 nm. 
     
     
         19 . The nanoscale structure of  claim 11  wherein said at least one pillar ( 120 ) is one of a plurality of pillars extending from said surface of the substrate ( 110 ). 
     
     
         20 . The nanoscale structure of  claim 19  wherein a spacing between pillars ( 120 ) in said plurality of pillars is in the range from 2 nm to 4,000 nm. 
     
     
         21 .- 43 . (canceled)