Development of a Low-Cost PCB-Based High-Frequency AC Susceptometer for Magnetic Materials Characterization

Abstract

This thesis presents the development and performance evaluation of femtoMag, a novel, cost-effective high-frequency AC susceptometer designed to characterize magnetic materials up to 200 MHz. Leveraging a low-cost printed circuit board (PCB) design and commercially available high-frequency electronics, femtoMag addresses limitations in conventional susceptometry by enabling measurements of magnetic powders and thin films without requiring specific geometries or extensive sample preparation. The design employs a PCB-based low-inductance single-turn coil, which enhances the sensor's performance at higher frequencies compared to traditional multi-turn coil designs. Electromagnetic properties of the system were modeled using ANSYS HFSS simulations, while physical components were created with Autodesk Fusion 360 and DipTrace. Performance validation was conducted using reference samples with known permeability values, showing close agreement with conventional measurement methods. This work highlights femtoMag's simplicity, cost-efficiency, and reliability in providing accurate magnetic characterization data, establishing it as a powerful tool for diverse magnetic material studies, particularly in cases where sample quantities or geometries are limited