Bondwire impedance compensation using a series transmission line section

Bondwires at millimeter-wave frequencies show a high impedance mismatch that limits their applications in signal transmission from chip-to-chip, chip-to-package or vice-versa. Using a series transmission-line section and embedding the bondwire and the compensating circuit in an epoxy, we improved the matching and reduced the insertion loss. Furthermore, by changing the length of the compensating transmission line and the wire length, the technique can be used over a bandwidth of more than 10 GHz at mm-waves. The measured results for a wire length of 0.7 mm with the matching section a 0.425 mm show an impedance matching with S11 below -6 dB and a simulated insertion loss of 0.35 dB over a 10 GHz bandwidth.