Flip-Chip Approach for 500 GHz Broadband Interconnects

S. Sinha, R. Doerner, F.-J. Schmückle, S. Monayakul, M. Hrobak, N.G. Weimann, V. Krozer, and W. Heinrich

Published in:

IEEE Trans. Microwave Theory Tech., vol. 65, no. 4, pp. 1215-1225 (2017).

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This paper presents the design and characterization of a broadband transition in the range dc to 500 GHz using the flip-chip concept. The extremely wideband performance is attained by optimizations in both process technology and electromagnetic design. On the process technology side, a thinfilm process with scaled dimensions of 10 µm for via diameter and 2 µm bump height is employed for the chip and the carrier substrate. On the electromagnetic side, in addition to impedance matching, a detailed analysis of parasitic modes is considered for the design. The measurement results show less than 0.9-dB insertion loss per transition at 500 GHz and reflections below -18 dB over the entire dc to 500 GHz band.

Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik im Forschungsverband Berlin e.V., D-12489 Berlin, Germany

Index Terms:

Benzocyclobutene (BCB), flip chip, interconnect, terahertz.