Sensor of volatile substances and process for manufacturing a sensor of volatile substances
A sensor of volatile substances includes: a first electrode structure and a second electrode structure capacitively coupled, comb-fingered, and arranged coplanar in a plane; and a sensitive layer, of a sensitive material that is permeable to a volatile substance and has electrical permittivity depending upon a concentration of the volatile substance absorbed by the sensitive material. The sensitive layer extends from opposite sides of the plane.
1. A device, comprising:
a substrate;
a first dielectric layer on the substrate, the first dielectric layer including a plurality of first and second supporting structures that extend away from the substrate and form a recess;
a first electrode structure on the plurality of first supporting structures and located at the recess;
a second electrode structure on the plurality of second supporting structures and located at the recess; and
a sensitive layer on the first and second electrode structure, the sensitive layer covering the first and second electrode structures and filling the recess.
2. The device of claim 1 wherein the sensitive layer is adjacent to sidewalls of the supporting structures.
3. The device of claim 2 , further comprising a second dielectric layer on the sensitive layer, the second dielectric layer including a window.
4. The device of claim 1 wherein the first and second supporting structures are positioned in an alternating arrangement.
5. The device of claim 1 wherein the sensitive layer is a hygroscopic polymeric material.
6. A device, comprising:
a substrate;
a first dielectric layer on the substrate, the first dielectric layer including a main portion, a first plurality of support structures, and a second plurality of support structures, the first and second plurality of support structures extending from the main portion;
a first electrode structure on the first dielectric layer and supported by the first plurality of support structures;
a second electrode structure on the first dielectric layer and supported by the second plurality of support structures; and
a sensitive layer on the first and second electrode structure, the sensitive layer configured to detect volatile substances.
7. The device of claim 6 , further comprising a second dielectric layer on the sensitive layer, the second dielectric layer including a window.
8. The device of claim 6 wherein the first and second electrode structures are positioned in an alternating arrangement.
9. The device of claim 6 wherein first plurality of support structures include a main portion extending in a first direction and a plurality of teeth extending in a second direction.
10. The device of claim 9 wherein the second direction is perpendicular to the first direction.
11. The device of claim 9 wherein the sensitive layer is a hygroscopic polymeric material.
12. A device comprising:
a substrate;
a first dielectric layer on the substrate;
a first electrode structure on the first dielectric layer;
a second electrode structure on the first dielectric layer;
a first plurality of support structures that extend away from the substrate, each of the first plurality of support structures including a first portion of the first dielectric layer and a portion of the first electrode structure on the first portion of the first dielectric layer; and
a second plurality of support structures that extend away from the substrate, each of the second plurality of support structures including a second portion of the first dielectric layer and a portion of the second electrode structure on the second portion of the first dielectric layer,
wherein each portion of the first electrode structure has a same width as the respective first portion of the first dielectric layer for the first plurality of support structures.
13. The device of claim 12 , wherein each portion of the second electrode structure has a same width as the respective second portion of the first dielectric layer for the second plurality of support structures.
14. The device of claim 12 , further comprising a sensitive layer on the first and second electrode structure, the sensitive layer configured to detect volatile substances.