Multi-layer-multi-turn high efficiency inductors with cavity structures
A multi-layer, multi-turn structure for an inductor having a plurality of conductor layers separated by layers of insulator is described. The inductor further comprises a connector electrically connected between the conductor layers. The structure of the inductor may comprise a cavity therewithin. The structure of the inductor constructed such that electrical resistance is reduced therewithin, thus increasing the efficiency of the inductor. The inductor is particularly useful at operating within the radio frequency range and greater.
1. An inductor comprising:
a) a first conductor layer;
b) a second conductor layer spaced apart from the first conductor layer, the first conductor layer and the second conductor layer being electrically conductive;
c) an insulator layer positioned in the space between the first conductor layer and the second conductor layer thereby forming a structure, wherein an inductor cavity having an inductor cavity width, an inductor cavity length, and an inductor cavity depth resides therewithin;
d) at least one connector electrically connecting the first conductor layer and the second conductor layer; and
e) wherein when an electrical current is propagated within at least the first conductor layer, a magnetic flux is generated within the inductor; and
f) wherein when a change in at least one of a frequency, a magnitude, or a waveform shape of the propagated electrical current occurs an inductance is generated.
2. The inductor of claim 1 wherein an electromotive force is generated when at least one of the frequency, the magnitude, or the waveform shape of the electrical current is changed.
3. The inductor of claim 2 wherein a magnitude of the magnetic flux is proportional to the amount of change of at least one of the frequency, the magnitude, or the waveform shape of the electrical current.
4. The inductor of claim 1 wherein, an electrical resistance of at least one of the first conductor layer is reducible when a cross-sectional area of a conducting skin depth within at least the first conductor layer is increased.
5. The inductor of claim 1 wherein a thickness of the first conductor layer is about equal to a thickness of a skin depth of the first conductor layer at a given frequency.
6. The inductor of claim 1 wherein a thickness of the first conductor layer ranges from about 1.25 times to about 4 times a thickness of a skin depth of the first conductor layer at a given frequency.
7. The inductor of claim 1 wherein a thickness of the second conductor layer ranges from about 1.25 times to about 4 times a thickness of a skin depth of the second conductor layer at a given frequency.
8. The inductor of claim 1 wherein a first conductor layer thickness is about the same as a second conductor layer thickness.
9. The inductor of claim 1 wherein a first conductor layer thickness is different from a second conductor layer thickness.
10. The inductor of claim 1 wherein a thickness of a first skin depth of the first conductor layer is about the same as a thickness of a second skin depth of the second conductor layer.
11. The inductor of claim 1 wherein a thickness of a first skin depth of the first conductor layer is different than a thickness of a second skin depth of the second conductor layer.
12. The inductor of claim 1 wherein a thickness of the insulating layer is less than about 5 cm.
13. The inductor of claim 1 wherein the inductor has an inductor quality factor greater than about 5.
14. The inductor of claim 1 wherein the insulator layer comprises a first material having a first dielectric constant and a second material having a second dielectric constant, the second material resides within the cavity, the first and second dielectric constants are not equal.
15. The inductor of claim 14 wherein the second material is selected from the group consisting of a polymeric material, a piezoelectric material, a pyroelectric material, and combinations thereof.
16. The inductor of claim 1 wherein the cavity width ranges from about 80 percent to about 99 percent of an inductor width.
17. The inductor of claim 1 wherein the cavity length ranges from about 80percent to about 99 percent of an inductor length.
18. The inductor of claim 1 wherein the cavity depth is about equal to an inductor depth, such that the cavity extends through a top inductor surface and a bottom inductor surface.
19. The inductor of claim 1 wherein the cavity depth is less than an inductor depth, such that the cavity resides between a top inductor surface and a bottom inductor surface.
20. The inductor of claim 13 wherein the inductor quality factor is defined by the equation
Q
=
2
π
fL
R
where f is the frequency of operation, L is the inductance, and R is the total ohmic and radiative resistance.
21. The inductor of claim 1 wherein the frequency is at least 3 kHz.
22. The inductor of claim 1 wherein at least one of the first and second conductor layers is formed from a thermally conductive material.
23. The inductor of claim 1 wherein the connector is selected from the group of a via, a solder, a tab, a wire, a pin, a rivet, a filled mesh structure, a conductive polymer, a conductive composite, a conductive adhesive, a liquid metal, a foamed metal, and combinations thereof.
24. The inductor of claim 1 wherein at least one connector electrically connects the first conductor layer and the second conductor layer in parallel.
25. The inductor of claim 1 wherein the first conductor layer and the second conductor layer form a structure in which the first and second conductor layers are positioned in about a parallel orientation, about perpendicular, or at an angular relationship with respect to each other.
26. The inductor of claim 1 comprising a third conductor layer and a fourth conductor layer electrically connected in parallel or series and are further connected electrically in series or parallel with the third and fourth conductor layers.
27. The inductor of claim 1 wherein the inductor is electrically connectable with an electrical circuit operating at about 100 kHz or greater.
28. The inductor of claim 27 wherein the electrical circuit is selected from the group consisting of a mixer circuit, an impedance matching circuit, an upconverting mixer circuit, a downconverting mixer circuit, a modulator, a demodulator, a synthesizing circuit, a PLL synthesizing circuit, an amplifying circuit, an electrical driver circuit, an electrical detecting circuit, an RF log detector, an RF RMS detector, an electrical transceiver, a power controller, and combinations thereof.
29. The inductor of claim 1 wherein the inductor is electrically connectable within an induction heating circuit.
30. The inductor of claim 1 wherein a control circuit is electrically connectable to the inductor.
31. The inductor of claim 1 wherein at least the first and second conductor layers has at least a partial revolution.
32. The inductor of claim 1 wherein the first conductor layer or the second conductor layer comprises a material selected from the group consisting of copper, titanium, platinum, platinum and iridium alloys, tantalum, niobium, zirconium, hafnium, nitinol, cobalt-chromium-nickel alloys, stainless steel, gold, a gold alloy, palladium, carbon, silver, a noble metal, a conductive polymer, a conductive adhesive, a conductive composite, a liquid metal, a foamed metal, a conductive tape, a conductive ribbon, a conductive foil, a conductive leaf, a wire, a deposited metal, a biocompatible material, and combinations thereof.
33. The inductor of claim 1 wherein at least one insulator layer is formed from an electrically insulative material.
34. The inductor of claim 1 wherein the insulator layer comprises an electrically insulative material selected from the group consisting of air, polystyrene, silicon dioxide, a biocompatible ceramic, a conductive dielectric material, a non-conductive dielectric material, a piezoelectric material, a pyroelectric material, a ferrite material, and combinations thereof.
35. An inductor comprising:
a) a first inductor subassembly comprising:
i) a first conductive conductor layer;
ii) a second conductive conductor layer spaced apart from the first conductor layer, the first conductor layer and the second conductor layer being electrically conductive;
iii) a first insulator layer positioned in the space between the first conductor layer and the second conductor layers;
iv) a first cavity having a first cavity width, a first cavity length, and a first cavity depth residing within the first inductor subassembly; and
v) a first connector electrically connecting the first conductor layer and the second conductor layer in parallel;
b) a second inductor subassembly comprising:
i) a third conductor layer and a fourth conductor layer spaced apart from the third conductor layer, the third conductor layer and the fourth conductor layer being electrically conductive;
ii) a second insulator layer positioned in the space between the third conductor layer and the fourth conductor layers;
iii) a second cavity having a second cavity width, a second cavity length, and a second cavity depth residing within the second inductor subassembly; and
iv) a second connector electrically connecting the third conductor layer and the fourth conductor layer in parallel, wherein the first inductor subassembly is electrically connected in series to the second inductor subassembly; and
c) wherein when an electrical current is propagated within at least the first conductor layer, a magnetic flux is generated within the inductor; and
d) wherein when a change in at least one of a frequency, a magnitude, or a waveform shape of the propagated electrical current occurs, an inductance is generated.
36. The inductor of claim 35 wherein the first inductor subassembly and the second inductor subassembly are oriented such that the first and second inductor subassemblies are positioned about parallel, about perpendicular, or at an angular relationship with respect to each other.