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Collector Series-Resistor to Stabilize a Broadband 400 GHz Common-Base Amplifier



Jerome Cheron, Dylan Williams, Richard Chamberlin, Miguel Urteaga, Kassi Smith, Nick Jungwirth, Bryan Bosworth, Chris Long, Nate Orloff, Ari Feldman


The indium phosphide (InP) 130 nm double-heterojunction bipolar transistor (DHBT) offers milliwatts of output power and high signal amplification in the lower end of the terahertz frequency band when the transistor is used in a common-base configuration. Instrumentation can directly benefit from this technology by enabling the development of novel broadband sources or synthesizers that rely on our ability to amplify the signal over enormous bandwidths. However, the design of high gain and stable amplifiers presents many obstacles and limitations as we increase the bandwidth and the carrier frequency. Here we show that adding a series resistor at the collector terminal of the common-base transistor prevents instabilities in the terahertz monolithic integrated circuit (TMIC) amplifier and increases its fractional bandwidth. Adopting this technique, we report a state-of-the-art broadband common-base amplifier that exhibits a minimum small-signal gain of 18.9 dB from 325 GHz to 477 GHz. This amplifier presents the highest fractional bandwidth and gain above 300 GHz. Our work demonstrates the feasibility of high-performance amplifiers that address the need of future terahertz electronic systems.
IEEE Transactions on Terahertz Science and Technology


Submillimeter-wave, terahertz monolithic integrated circuit (TMIC), broadband amplifier, common-base amplifier, indium phosphide (InP), double heterojunction bipolar transistor (DHBT).


Cheron, J. , Williams, D. , Chamberlin, R. , Urteaga, M. , Smith, K. , Jungwirth, N. , Bosworth, B. , Long, C. , Orloff, N. and Feldman, A. (2021), Collector Series-Resistor to Stabilize a Broadband 400 GHz Common-Base Amplifier, IEEE Transactions on Terahertz Science and Technology, [online],, (Accessed June 18, 2024)


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Created October 14, 2021, Updated November 29, 2022