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(12) United States Patent
Lotfi et al.
(io) Patent No.: (45) Date of Patent:
US 7,920,042 B2 Apr. 5, 2011
(54) MICROMAGNETIC DEVICE AND METHOD OF FORMING THE SAME
(75) Inventors: Ashraf W. Lotfi, Bridgewater, NJ (US);
Trifon M. Liakopoulos, Bridgewater, NJ
(US); Robert W. Filas, Basking Ridge,
NJ (US); Amrit Panda, San Jose, CA
(73) Assignee: Enpirion, Inc., Hampton, NJ (US)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 662 days.
(21) Appl.No.: 11/852,688
(22) Filed: Sep. 10, 2007
A micromagnetic device includes a first insulating layer formed above a substrate, a first seed layer formed above the first insulating layer, a first conductive winding layer selectively formed above the first seed layer, and a second insulating layer formed above the first conductive winding layer. The micromagnetic device also includes a first magnetic core layer formed above the second insulating layer, a third insulating layer formed above the first magnetic core layer, and a second magnetic core layer formed above the third insulating layer. The micromagnetic device still further includes a fourth insulating layer formed above the second magnetic core layer, a second seed layer formed above the fourth insulating layer, and a second conductive winding layer formed above the second seed layer and in vias to the first conductive winding layer. The first and second conductive winding layers form a winding for the micromagnetic device.
30 Claims, 25 Drawing Sheets
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* cited by examiner