A team of researchers has developed a cutting-edge 3-axis Hall-effect magnetic sensor featuring an inverted pyramid structure. This novel design significantly enhances sensitivity and reduces offset, making it a promising solution for applications requiring precise and reliable magnetic field detection in automotive, industrial, and consumer electronics.
State-of-the-art and 3-axis pyramid device. a Our novel pyramid Hall device. b A standard 3-axis Hall sensor, composed of one planar Hall device and two vertical Hall devices. c The flat 8-contact Hall device, proposed by Schott9. d Sander’s hexagonal prism Hall device11. e An IMC Hall device12. f SEM image of the pyramid device, with a tilting angle of 30°. g SEM image of the pyramid device, with no tilting angle. h Optical microscope image of the sensor. The pyramid size and the contact dimensions are highlighted in the picture. Image Credit: Microsystems & Nanoengineering
Hall-effect magnetic sensors play a crucial role across various industries, including automotive, industrial automation, consumer electronics, and medical devices. While these sensors are known for their reliability and affordability, existing 3-axis models often struggle with limited sensitivity, large footprints, and high offsets. These challenges hinder their ability to meet the growing demand for miniaturization and precision in modern electronics. As devices continue to shrink while demanding greater accuracy, the need for improved magnetic sensing solutions has never been more pressing.
In a study published in Microsystems & Nanoengineering, researchers from the Department of Microelectronics at Delft University of Technology introduced a 3-axis Hall-effect magnetic sensor with an inverted pyramid structure.
By leveraging a combination of micro-electromechanical systems (MEMS) micromachining and complementary metal-oxide semiconductor (CMOS) processing, the sensor can detect both in-plane and out-of-plane magnetic fields within a compact form factor. It surpasses traditional Hall sensors by utilizing an advanced current-spinning method, which reduces offset by one to three orders of magnitude—a critical improvement for accurate magnetic field sensing.
Performance tests highlight the sensor’s impressive capabilities, including high current-related sensitivity ranging from 64.1 to 198 V A−1 T−1 and voltage-related sensitivity between 14.8 and 21.4 mV V−1 T−1. Additionally, it features a low crosstalk rate of under 4.7 %, ensuring precise readings, and a thermal noise floor of approximately 0.5 μT/√Hz, making it well-suited for high-precision applications.
The compact design integrates multiple sensing modes into a single structure, significantly reducing its footprint and enhancing isotropy compared to existing solutions. While the sensor shows considerable advancements, some residual offset remains in the millitesla range, indicating room for further refinement.
This novel sensor represents a significant step forward in magnetic sensing technology. By integrating an inverted pyramid structure with current-spinning, we have achieved remarkable improvements in sensitivity and offset reduction, paving the way for more precise and reliable magnetic field sensing.
Dr. Karen M. Dowling, Assistant Professor, Delft University of Technology
The potential applications for this advanced 3-axis Hall-effect sensor are vast, particularly in fields requiring highly precise magnetic sensing. Its compact and high-performance design makes it ideal for position feedback, power monitoring, and robotic motion tracking. As further optimizations are made, this technology could drive improvements in sensor integration across various industries, enhancing efficiency and reliability in everyday devices.
Journal Reference:
Ruggeri, J., et. al. (2025) Inverted pyramid 3-axis silicon Hall-effect magnetic sensor with offset cancellation. Microsystems & Nanoengineering. doi.org/10.1038/s41378-025-00876-9