Miniaturized double-wing ∆E-effect magnetic field sensors.

Area of Science:

• Materials Science
• Micro-electromechanical Systems (MEMS)
• Magnetism

Background:

• Magnetoelastic MEMS rely on magnetostriction, but are sensitive to stress-induced magnetic anisotropy.
• Fabrication-induced residual stress impairs device reproducibility, performance, and yield in magnetoelastic layers.
• Minimizing stress is crucial for reliable and high-performance magnetoelastic devices.

Purpose of the Study:

• To develop a fabrication technique that prevents residual stress transfer to the magnetoelastic layer.
• To investigate the performance of magnetoelectric microresonators under minimized stress conditions.
• To enhance the reproducibility and sensitivity of magnetoelastic MEMS devices.

Main Methods:

• Utilized shadow mask deposition technology to prevent stress transfer to the magnetic layer.
• Employed a free-free magnetoelectric microresonator design to mitigate magnetic inhomogeneity.
• Conducted experimental and theoretical analysis of magnetoelectric resonators, focusing on stress anisotropy, magnetic anisotropy, and ΔE-effect sensitivity.

Main Results:

• Achieved exceptionally small device-to-device resonance frequency variation (<0.2%).
• Demonstrated high ΔE-effect sensitivity comparable to macroscopic magnetic field sensors.
• Validated the effectiveness of the shadow mask deposition and free-free resonator design.

Conclusions:

• The developed method significantly improves the reproducibility of magnetoelastic devices.
• This approach paves the way for large-scale, integrated arrays of high-performance magnetoelastic MEMS.
• The findings represent a promising advancement for the practical application of magnetoelastic sensors and actuators.