Capacitor structure, display device having capacitor structure, and manufacturing method of capacitor structure
View Patent ↗A capacitor structure includes: a first substrate having a first electrode part provided on one surface thereof; a second substrate having a second electrode part provided on a surface thereof, which faces the first substrate; and a dielectric layer provided between the first substrate and the second substrate, wherein a Poisson's ratio of the first substrate or the second substrate is different from a Poisson's ratio of the dielectric layer. The capacitor structure has a substantially constant capacitance even when the capacitor structure is exposed to external strain.
1. A capacitor structure, comprising:
a first substrate, wherein the first substrate comprises a first electrode part disposed on one surface of the first substrate;
a second substrate, wherein the second substrate comprises a second electrode part disposed on a surface of the second substrate, the surface of the second substrate faces the first substrate; and
a dielectric layer disposed between the first substrate and the second substrate,
wherein a Poisson's ratio of the first substrate or the second substrate is at least 0.2 greater than a Poisson's ratio of the dielectric layer, and
wherein a thickness of the dielectric layer is less than a thickness of the first substrate and less than a thickness of the second substrate.
2. The capacitor structure of claim 1 , wherein the first substrate, the second substrate, and the dielectric layer are contracted or stretched in a first coordinate direction, a second coordinate direction, and a third coordinate direction.
3. The capacitor structure of claim 2 , wherein a shape change of the dielectric layer in the third coordinate direction with respect to a strain applied in the first coordinate direction or the second coordinate direction is smaller than a shape change of the dielectric layer in the first coordinate direction or a shape change of the dielectric layer in the second coordinate direction.
4. The capacitor structure of claim 2 , wherein the first coordinate direction, the second coordinate direction, and the third coordinate direction constitute a coordinate system selected from a group consisting of a Cartesian coordinate system, a cylindrical coordinate system, and a spherical coordinate system.
5. The capacitor structure of claim 1 , wherein the first electrode part is embedded in the first substrate and the second electrode part is embedded in the second substrate.
6. The capacitor structure of claim 5 , wherein the first electrode part and the second electrode part further comprise a wire-shaped conductor.
7. The capacitor structure of claim 1 , wherein surfaces of the first substrate and the second substrate are hydrophobic.
8. A display device comprising:
the capacitor structure of claim 1 ; and
a display unit configured to display an image.
9. The display device of claim 8 , further comprising a touch sensing unit configured to recognize a touch of a user, wherein the capacitor structure is disposed in the touch sensing unit.
10. The display device of claim 8 , further comprising a transistor for driving the display device, wherein the capacitor structure is disposed in the transistor.
11. A method of manufacturing a capacitor structure, the method comprising:
preparing a first substrate;
forming a mask on the first substrate;
surface-treating an area of the first substrate, which is exposed without the mask;
forming a first electrode part on the surface-treated area of the first substrate;
forming a dielectric layer on the first substrate; and
forming a second electrode part and a second substrate on the dielectric layer,
wherein a Poisson's ratio of the first substrate or the second substrate is at least 0.2 greater than a Poisson's ratio of the dielectric layer, and
wherein a thickness of the dielectric layer is less than a thickness of the first substrate and less than a thickness of the second substrate.
12. The method of claim 11 , wherein the surface-treated area of the first substrate is hydrophilic, and another area of the first substrate, which is not surface-treated, is hydrophobic.
13. The method of claim 11 , wherein the first electrode part is formed by coating a hydrophilic resin composition on the first substrate.
14. The method of claim 13 , wherein the hydrophilic resin composition comprises a wire-shaped conductor.
15. The method of claim 11 , wherein the surface-treating further comprises oxygen-plasma treating the first substrate.
16. The method of claim 11 , wherein the forming of the second electrode part and the second substrate comprises:
forming a mask on the second substrate;
surface-treating an area of the second substrate, which is exposed without the mask; and
forming the second electrode part on the surface-treated area of the second substrate.