A miniature thin-film shielded-loop probe with a flip-chip bonding for magnetic near field measurements

In order to obtain EMC design information, it is important to accurately evaluate the near field of LSI chips and printed circuit boards as well as the interconnect currents. In particular, the need for measurement of LSI, considered as a source of noise, has increased. The authors have developed miniature shielded loop probes by using a thin film process. There is a problem that electromagnetic shielding at the wire bonding junctions for the loop output has not been sufficient. In the present paper, a new miniature shielded loop probe configuration is proposed in which the loop output is extracted by means of flip-chip bonding, which is expected to improve the shielding capability and reduce insertion loss. The effectiveness of the flip-chip bonding is demonstrated by an evaluation of magnetic field detection by the fabricated probe near interconnections.