Flip-Chip Interconnects for 250 GHz Modules

S. Monayakul1, S. Sinha1, C.-T. Wang2, N. Weimann1, F.J. Schmückle1, M. Hrobak1, V. Krozer1, W. John1, L. Weixelbaum1, P. Wolter1, O. Krüger1, and W. Heinrich1

Published in:

IEEE Microwave Wireless Compon. Lett., vol. 25, no. 6, pp. 358-360 (2015).

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With the increasing availability of MMICs at frequencies beyond 100 GHz low-loss interconnects for module fabrication in this frequency range become essential. This letter presents results on a flip-chip mounting approach exhibiting a bandwidth of more than 250 GHz, supporting both coplanar and stripline transitions. The interconnects are realized with 10µ-diameter AuSn microbumps. S-parameter measurements show an insertion loss of less than 1.0 dB per interconnect and a return loss better than 10 dB up to 250 GHz. The experimental results are in good agreement with 3-D EM simulations.

1 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany
2 Department of Materials Science and Engineering at National Chiao Tung University, Hsinchu 300, Taiwan

Index Terms:

Broadband transitions, coplanar waveguide, flipchip, interconnect, mm-wave, stripline.