Magnetic Field Imaging for 3D applications

摘要

Magnetic Field Imaging (MFI), using a Superconducting Quantum Interference Device (SQUID) as the sensing element, was first introduced in 1998 as a way to localize short failures in Integrated Circuits (ICs) by sensing the magnetic field generated by currents in the metal traces. Ten years ago, giant-magnetoresistive (GMR) sensor was added as a second sensor to allow for higher resolution MFI and accurate Fault Isolation (FI) at die level when the sensor can be brought in close proximity to the circuitry. This magnetic field data is typically analyzed using a standard inversion technique to obtain a current density map of the current paths for comparison with layout or other visualization methods.