Magnetic core

About: Magnetic core is a research topic. Over the lifetime, 30011 publications have been published within this topic receiving 155247 citations.

Inductively coupled plasma processing apparatus

Abstract: An inductively coupled plasma processing apparatus (100) comprises a plasma chamber (12) with a dielectric window (400) forming a self-supporting wall element of the plasma chamber (12). The dielectric window (400) has an external and an internal side with respect to the chamber (12). An electromagnetic field source (140) is arranged in front of the external side of the dielectric window (400) for generating an electromagnetic field within the plasma chamber (12). The field source comprises at least one magnetic core (301, 302, 303). The at least one magnetic core (301, 302, 303) is attached to the external side of the dielectric window (400), such that the at least one magnetic core helps the dielectric window (400) to withstand collapsing forces caused by negative pressure inside said chamber during operation.

Introduction to modeling of transformers and coupled inductors

Abstract: A tutorial paper is presented on modeling and design of transformers and coupled inductors. Beginning with a brief review of electromagnetic laws and magnetic circuit models, the magnetic and electric models of transformers and coupled inductors are developed, including both magnetizing and leakage effects. It is shown that while the voltage waveforms on the windings are primarily related by the turns ratio for both devices, the winding currents of transformers and coupled inductors are determined by very different mechanisms. An integrated structure with both transformer and coupled inductor on the same core is also discussed, as well as the special case of the coupled inductor used on a multiple-output transformer-isolated converter. >

On modelling iron core nonlinearities

Abstract: An algorithm is presented for the computation of the saturation characteristics of transformer iron cores based on supplied conventional V/sub rms/-I/sub rms/ curves and no-load losses at rated frequency. Laboratory measurements on a steel sample were carried out. It is shown that the iron core losses are a nonlinear function of the applied voltage. Taking these losses into account improves the nonlinear flux-current characteristics. >

Integrated on-chip inductors using magnetic material (invited)

Abstract: On-chip inductors with magnetic material are integrated into both advanced 130 and 90 nm complementary metal-oxide semiconductor processes. The inductors use aluminum or copper metallization and amorphous CoZrTa magnetic material. Increases in inductance of up to 28 times corresponding to inductance densities of up to 1.3 μ H / mm 2 were obtained, significantly greater than prior values for on-chip inductors. With such improvements, the effects of eddy currents, skin effect, and proximity effect become clearly visible at higher frequencies. The CoZrTa was chosen for its good combination of high permeability, good high-temperature stability ( > 250 ° C ) , high saturation magnetization, low magnetostriction, high resistivity, minimal hysteretic loss, and compatibility with silicon technology. The CoZrTa alloy can operate at frequencies up to 9.8 GHz , but trade-offs exist between frequency, inductance, and quality factor. The effects of increasing the magnetic thickness on the permeability spectra were measured and modeled. The inductors use magnetic vias and elongated structures to take advantage of the uniaxial magnetic anisotropy. Techniques are presented to extract a sheet inductance and examine the effects of magnetic vias on the inductors. The inductors with thick copper and thicker magnetic films have resistances as low as 0.04 Ω , and quality factors up to 8 at frequencies as low as 40 MHz.

Integrated inductive components and method of fabricating such components

Abstract: An inductive component includes a substrate (12) on the surface of which is a lower insulation layer (32) having a shallow concavity (34) or trench, a first plurality of conductive elements (16) formed in the trench, a magnetic core (14) formed over the first plurality of conductive elements, and a second plurality of conductive elements (18) formed over the core. The first and second pluralities of conductive elements are connected to each other so as to form an inductive coil around the core. First and second core insulation layers (28, 30) are disposed between the core and the first and second pluralities of conductive elements, respectively. The component is fabricated by a method in which it is built up in the trench using thin film techniques. A first array of conductors (16) is patterned over the lower insulation layer (34), and a first core insulation layer (28) is applied over the first conductor array. A magnetic core (14) is formed on top of the first core insulation layer, and a second core insulation layer (30) is applied over the core. A second array of conductors (18) is patterned on top of the second core insulation layer so that the ends of the conductors in the first and second arrays contact each other to form an inductive coil around the core. The formation of either the first or second plurality of conductors may coincide with the formation of the metal conductor layer in the manufacture of a semiconductor integrated circuit, whereby the inductive component can be manufactured as part of the integrated circuit.