Smaller computer chips are not only a transistor challenge. The components that deliver steady, controlled power to those transistors also need to fit into increasingly compact electronics. A tiny inductor made with a nickel and iron oxide nanocomposite showed more than twice the inductance of comparable devices without a magnetic core, according to a report on a published study.

Sai Pranesh Amirisetti’s Science X Dialog report describes research conducted at the University of Florida with coauthors Brenden M. Mears, Noah Morgan, Jennifer S. Andrew and David P. Arnold. The study was published in the Journal of Micromechanics and Microengineering. The work explores a way to build magnetic material into a microfabricated inductor, a component that can help regulate electrical power.

In many switching voltage regulators, an inductor temporarily stores energy in a magnetic field and helps control changes in current. Together with other components, it helps turn rapidly switched power into a steadier supply. But shrinking an inductor generally reduces the inductance available from a given design. Adding magnetic material can increase the magnetic flux linked to the conductor, though the material must also handle rapid changes without dissipating too much energy.

The team made its composite by starting with iron oxide nanoparticles and electrochemically depositing nickel into the spaces between them. They then incorporated the material into stripline microinductors: an electrically insulated copper strip sits between upper and lower magnetic layers, which provide a path for magnetic flux around the conductor.

Fabricating the layered structure posed a practical challenge. Steep sides on the insulation over the copper made it difficult to form the upper magnetic layer continuously. The researchers used heat-softened photoresist to create a more rounded profile. That allowed them to increase the copper thickness from about 2 to 6 micrometers while maintaining magnetic coverage; the thicker conductor reduced winding resistance.

The devices reached about 1.6 nanohenries of inductance, more than twice that of comparable air-core devices. The team also measured quality factor, or Q, which describes the balance between inductive behavior and electrical loss at a given frequency. The optimized device had a peak Q of 5.3 at 150 megahertz, a 58% increase over the original process, which had a peak Q of 3.35.

Those are measurements of a microinductor, not of a complete voltage regulator. Higher inductance by itself does not establish that a power converter will work better: resistance, magnetic losses, current handling and temperature also matter. In a separate test, a co-fabricated one-port inductor’s inductance stayed approximately stable through 330 milliamperes under direct-current bias, measured at 1 megahertz. That indicates no measurable magnetic saturation within that test range; it does not establish the optimized device’s current rating at 150 megahertz.

The approach points toward a possible route for placing power-conversion components closer to the circuits they supply, including within a semiconductor package. But the report identifies further work on heating, reliability and performance in complete converters. Fabrication yield also needs improvement: 64 of 97 tested devices functioned. The study therefore establishes a device-level materials and fabrication result, not a demonstrated reduction in the energy use of a finished processor.

<a href="https://phys.org/news/2026-11-magnetic-nanocomposites-components-power-chips.html">Source: Phys.org report</a>