Micro coil apparatus and manufacturing methods therefor
A method for manufacturing a conductive coil, the method comprising using a semiconductor fabrication process (e.g. TSV) to manufacture a coil, typically a planar spiral conductive coil.
1. An electric coil device comprising:
a spiral comprising a plurality of electro-conductive turns and an isolation layer between the turns, the isolation layer comprising a spiral trench of varying width formed of a surrounding electrically isolating bulk, the electro-conductive turns comprising an electro-conductive material at least partly filling said spiral trench; and connection feeds in and out of the spiral,
wherein the spiral is generally planar defining a coil plane and wherein the feeds extend both upward and downward from said coil plane, and
wherein the trench which varies in height includes a peripheral portion, an intermediate portion and a central portion and wherein the cross-sectional height of the intermediate portion is greater than the cross-sectional heights, e.g. common cross-sectional height if equal, of the peripheral and central portions.
2. A device according to claim 1 in which the bulk is formed of one of the following group of materials: Silicon, Pyrex, Polymer.
3. Electronic circuitry apparatus including a coil device according to claim 1 .
4. Electronic circuitry apparatus according to claim 3 which includes a plurality of coils and is operative to induce electromagnetic flux coupling.
5. Multi-level electrical coil apparatus comprising a stack of electrically connected electric coil devices according to claim 1 .
6. Apparatus according to claim 4 which comprises an electromagnetic actuator.
7. A device according to claim 1 wherein the trench which varies in height includes a peripheral portion, an intermediate portion and a central portion and wherein the cross-sectional height of the intermediate portion is greater than the cross-sectional heights, e.g. common cross-sectional height if equal, of the peripheral and central portions.
8. Apparatus according to claim 5 wherein the spiral in each electric coil device has top and bottom main surfaces and defines a hollow portion at its center extending through the top and bottom main surfaces such that the stack has a hollow center comprising a concatenation of the hollow portions of each of the electric coil devices as stacked.
9. Apparatus according to claim 8 and also comprising a ferromagnetic structure residing in the hollow center of the stack and extending along a plurality of the electric coil devices in the spiral.
10. A device according to claim 1 wherein a plurality of connecting points are provided on at least one of the upper surface of the trench and the lower surface thereof, thereby providing diverse options for connectivity.
11. A device according to claim 1 wherein connecting points are provided at both ends of the trench on both the upper and lower surfaces of the trench, thereby providing diverse options for connectivity.
12. Apparatus according to claim 9 which includes electrical connection apparatus between the stack and an electrical circuit, thereby to generate an actuator.
13. An electric coil device comprising:
a generally planar spiral defining a coil plane and comprising a plurality of electro-conductive turns and an isolation layer between the turns, the isolation layer comprising a spiral trench of varying width formed of an electrically isolating material, the electro-conductive turns comprising an electro-conductive material at least partly filling said spiral trench; and
connection feeds in and out of the spiral which extend both upward and downward from said coil plane,
wherein the spiral in each electric coil device has top and bottom main surfaces and defines a hollow portion at its center extending through the top and bottom main surfaces such that the stack has a hollow center comprising a concatenation of the hollow portions of each of the electric coil devices as stacked.
14. Multi-level electrical coil apparatus comprising a stack of electrically connected electric coil devices according to claim 1 .
15. Apparatus according to claim 13 and also comprising a ferromagnetic structure residing in the hollow center of the stack and extending along a plurality of the electric coil devices in the spiral.
16. A device according to claim 1 wherein a plurality of connecting points are provided on at least one of the upper surface of the trench and the lower surface thereof, thereby providing diverse options for connectivity.
17. A device according to claim 1 wherein connecting points are provided at both ends of the trench on both the upper and lower surfaces of the trench, thereby providing diverse options for connectivity.
18. Apparatus according to claim 15 which includes electrical connection apparatus between the stack and an electrical circuit, thereby to generate an actuator.