Title :
Noise and spatial resolution in SQUID microscopy
Author :
Chatraphorn, S. ; Fleet, E.F. ; Wellstood, F.C. ; Knauss, L.A.
Author_Institution :
Dept. of Phys., Maryland Univ., College Park, MD, USA
fDate :
3/1/2001 12:00:00 AM
Abstract :
We have used a scanning SQUID microscope to image magnetic field generated by currents in integrated circuits. To obtain current paths in these circuits, we apply a magnetic inversion technique to the magnetic field data. We find that the spatial resolution obtained from this technique is related to the signal-to-noise ratio, the SQUID-sample separation and the data sampling interval. We describe in detail a mathematical model of how these parameters relate to the spatial resolution. Finally, we discuss the limitations of our apparatus, and how to achieve higher spatial resolution
Keywords :
SQUID magnetometers; integrated circuit testing; scanning probe microscopy; superconducting device noise; SQUID microscopy; SQUID-sample separation; current paths; currents; data sampling interval; integrated circuits; magnetic field; magnetic inversion technique; noise; scanning SQUID microscope; signal-to-noise ratio; spatial resolution; Image generation; Integrated circuit noise; Magnetic circuits; Magnetic fields; Magnetic force microscopy; Magnetic noise; Magnetic separation; SQUIDs; Signal to noise ratio; Spatial resolution;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
