Abstract
Miniaturization of electronic devices has making progress, resulting in smaller current flowing in extremely high-density LSI (large scale integration) or PCB (printed circuit board). However, measurements of such low local current have still been confronted with many difficulties because of the limitation on size of relatively large and cumbersome typical current sensors, lead to detecting general signals of a wide area. In this research, we propose the novel micron size and high sensitivity needle-type GMR probe in applications of non-contact measuring low currents coming from area narrower than 10-6 m2 with small signal crosstalk such as PCB current measurement and low bio magnetic signal detection. Low current of hundreds μA in high-density PCB tracks of 4×10-4 m pitch was measured with the signal crosstalk less than 10% and 5×10-6 A of nerve signal model was possible to be detected by micron size GMR probe.
