Wire inductors, so called bond wire connections, are used to connect active and passive circuit components as well as micro devices to the real world.
The freespace inductance of a wire of diameter and length is given [46,47] by
where the frequency-dependent correction factor is a function of bond wire diameter and its material skin depth is expressed as
where is the conductivity of the wire material. When is small, . The wire resistance is given by
with and .
The effect of the ground plane on the inductance valueof a wire has also been considered. If the wire is at a distance above the ground plane, it sees its image at from it. The wire and its image result in a mutual inductance. Since the image wire carries a current opposite to the current flow in the bond wire, the effective inductance of the bond wire becomes
Mirror is a strange model that is frequency independent. Whereas computations are valid, hypothesis are arguable. Indeed, they did the assumption that the ground plane is perfect that is really a zero order model in the high frequency domain.