Variable capacitors, composite materials
View Patent ↗Tunable capacitors ( 10, 20, 30, 40 ) have a dielectric material ( 16, 26, 36, 42 ) between electrodes, which dielectric material comprises an insulating material ( 17, 27, 37, 42 ) and electrically conductive material, ( 18, 28, 38, 48 ) e.g., conductive nanoparticulates, dispersed therein. In certain cases, enhanced tune-ability is achieved when the dielectric material comprises elongated nanoparticulates ( 38 ). Further enhanced tune-ability may be achieved by aligning elongated particulates in an electrode-to-electrode direction. Nanoparticulates may be produced by heating passivated nanoparticulates. Passivated nanoparticulates may be covalently bound within a polymeric matrix. High bias potential device structures can be formed with preferential mobilities.
1. A capacitor comprising:
a dielectric material;
a first electrode on or in said dielectric material;
a second electrode on or in said dielectric material and spaced from said first electrode; and
at least one strip of thinner conductive material on or in said dielectric material and between said electrodes, said at least one strip being made of a material that interacts with an RF field from either of said electrodes, to cause an increase in the capacitance of the capacitor.
2. The capacitor of claim 1 wherein said dielectric material comprises a polymeric material matrix and metal nanoparticulates covalently bound within said polymeric matrix.
3. A capacitor comprising a pair of electrodes and, between said electrodes, a dielectric material in accordance with claim 2 .
4. The capacitor of claim 1 wherein:
said at least one strip of conductive material comprises one strip of conductive material.
5. The capacitor of claim 1 wherein:
said at least one strip of conductive material comprises a plurality of strips of conductive material.
6. The capacitor of claim 1 wherein:
said plurality of strips of conductive material are alternately attached to positive and negative voltages of a biasing circuit.
7. The capacitor of claim 1 wherein:
said at least one strip of conductive material has a charge carrier mobility that is about 10 4 cm 2 /V·s or more.
8. The capacitor of claim 1 wherein:
said at least one strip of conductive material has a charge carrier mobility that is about 10 6 cm 2 /V·s or more.
9. The capacitor of claim 1 wherein:
said at least one strip of conductive material is a metal.
10. The capacitor of claim 1 wherein:
said dielectric material is tunable.
11. The capacitor of claim 1 wherein:
said at least one strip of conductive material comprises several layers.
12. The capacitor of claim 1 wherein said electrodes form a parallel plate capacitor.
13. The capacitor of claim 1 wherein said electrodes form a gap capacitor.
14. The capacitor of claim 1 which functions at a biasing voltage of 10 volts or less.
15. The capacitor of claim 1 which functions at a biasing voltage of 3 volts or less.
16. The capacitor of claim 1 wherein said electrodes are made of materials that have electron/hole mobilities of 10 3 cm 2 /V·s or less.
17. The capacitor of claim 1 wherein said electrodes are made of materials that have electron/hole mobilities of 10 −1 cm 2 /V·s or less.
18. The capacitor of claim 1 wherein said at least one strip of thinner conductive material is aligned generally with the electric field.
19. The capacitor of claim 1 wherein said at least one strip of thinner conductive material is aligned generally parallel to the electric field.