IMPRINTED THIN-FILM ELECTRONIC SENSOR STRUCTURE
An imprinted electronic sensor structure on a substrate for sensing an environmental factor includes a cured layer having a layer surface located on the substrate. Spatially separated micro-channels extend from the layer surface into the cured layer. A multi-layer micro-wire is formed in each micro-channel. Each multi-layer micro-wire includes at least a conductive layer and a reactive layer. The reactive layer is exposed to the environmental factor. The conductive layer is a cured electrical conductor located only within the micro-channel and at least a portion of the reactive layer responds to the environmental factor.
1 . An imprinted electronic sensor structure on a substrate for sensing an environmental factor, comprising:
a cured layer having a layer surface located on the substrate;
a plurality of spatially separated micro-channels extending from the layer surface into the cured layer;
a multi-layer micro-wire formed in each micro-channel, the multi-layer micro-wire including at least a conductive layer and a reactive layer, the reactive layer exposed to the environmental factor; and
wherein the conductive layer is a cured electrical conductor located only within the micro-channel and at least a portion of the reactive layer responds to the environmental factor.
2 . The imprinted electronic sensor structure of claim 1 ,
wherein the conductive layer is closer to the layer surface than at least a portion of the reactive layer within the micro-channel.
3 . The imprinted electronic sensor structure of claim 1 , wherein the micro-channels have a micro-channel bottom and micro-channel sides and wherein the reactive layer extends over the micro-channel bottom, the micro-channel sides, and the layer surface outside the micro-channels.
4 . The imprinted electronic sensor structure of claim 1 , wherein the reactive layer is closer to the layer surface than the conductive layer.
5 . The imprinted electronic sensor structure of claim 4 , wherein the reactive layer extends over the layer surface outside the micro-channels.
6 . The imprinted electronic sensor structure of claim 1 , further including an inert layer located between the conductive layer and the reactive layer, the inert layer preventing chemical reactions between the reactive layer and the conductive layer.
7 . The imprinted electronic sensor structure of claim 6 , wherein the inert layer includes gold.
8 . The imprinted electronic sensor structure of claim 1 , wherein the cured electrical conductor includes metal particles.
9 . The imprinted electronic sensor structure of claim 1 , wherein the micro-channels have a depth less than 20 microns.
10 . The imprinted electronic sensor structure of claim 1 , wherein the micro-channels have a micro-channel bottom, a micro-channel top, and micro-channel sides and wherein the micro-channel sides are not perpendicular to the layer surface.
11 . The imprinted electronic sensor structure of claim 10 , wherein micro-channel bottom has a surface area smaller than the surface area of the micro-channel top.
12 . The imprinted electronic sensor structure of claim 1 , wherein the multi-layer micro-wires are grouped into a first group of multi-layer micro-wires and a second group of multi-layer micro-wires different from the multi-layer micro-wires of the first group.
13 . The imprinted electronic sensor structure of claim 12 , wherein the first group of multi-layer micro-wires is interdigitated with the second group of multi-layer micro-wires.
14 . The imprinted electronic sensor structure of claim 12 , wherein the first group of multi-layer micro-wires are electrically connected and the second group of multi-layer micro-wires are electrically connected.
15 . The imprinted electronic sensor structure of claim 12 , further including a controller for electrically controlling the first and second groups of multi-layer micro-wires.
16 . The imprinted electronic sensor structure of claim 1 , wherein the environmental factor is a chemical, is heat, is moisture, is radiation, is a biological material, or combinations thereof.
17 . The imprinted electronic sensor structure of claim 1 , wherein the reactive layer response is an electrical response, amperometric response, a change in resistivity, conductivity, dielectric constant, absolute permittivity, or relative permittivity.
18 . The imprinted electronic sensor structure of claim 1 , wherein the reactive layer is a functionalized layer that responds to a specific environmental factor.
19 . The imprinted electronic sensor structure of claim 1 , wherein the reactive layer is thicker than the conductive layer.
20 . The imprinted electronic sensor structure of claim 1 , wherein the conductive layer is thicker than the reactive layer.
21 . The imprinted electronic sensor structure of claim 1 , wherein the reactive layer includes one or more of a polymer, polymer composites, enzymes, carbon nanotubes, functionalized carbon nanotubes, grapheme, functionalized graphene, thiol groups, amine groups, carboxylic groups, nano-particles, conductive nano-particles, and magnetic nano-particles.
22 . The imprinted electronic sensor structure of claim 1 , further including an optical sensor for sensing the optical state of the multi-layer micro-wires.
23 . The imprinted electronic sensor structure of claim 1 , wherein the substrate is a flexible substrate.
24 . An imprinted electronic sensor structure on a substrate, comprising:
a first cured layer having a layer surface located on the substrate;
a plurality of spatially separated micro-channels extending from the layer surface into the cured layer, the micro-channels having a micro-channel bottom and micro-channel sides; and
a second cured layer that extends over the micro-channel bottom, the micro-channel sides, and the layer surface.
25 . The imprinted electronic sensor structure of claim 24 , wherein the depth of the micro-channel is greater than the thickness of the second cured layer.