Design, Modelling and Characterization of a 3-Vppd 90-GBaud Over-110-GHz-Bandwidth Linear Driver in 0.5-μm InP DHBTs for Optical Communications

• Published in: 2021 IEEE BiCMOS and Compound Semiconductor Integrated Circuits and Technology Symposium (BCICTS) pp. 1 - 4
• Main Authors: Hersent, R., Johansen, Tom K., Nodjiadjim, V., Jorge, F., Duval, B., Blache, F., Riet, M., Mismer, C., Konczykowska, A.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 05-12-2021
• Subjects: 4-level pulse amplitude modulation (PAM-4); DH-HEMTs; high-speed integrated circuits; Indium Phosphide (InP) double heterojunction bipolar transistor (DHBT); Integrated circuit modeling; Large-swing linear modulator driver; Optical design; Optical fiber communication; Optical modulation; Power demand; Predictive models; Tb/s optical communications
• DOI: 10.1109/BCICTS50416.2021.9682463

In this article, we present the modelling, design and characterization of a 3-Vppd linear-output-swing 90-GBd PAM-4 modulator driver, realised in III-V Lab's in-house 0.5-μm InP DHBT technology (380/520-GHz {f_{T}/f_{{\max}}} , 4.2-V {BV_{\text{CE0}}} ). The driver exhibits 13-dB equalisation capabilities at 95 GHz with a bandwidth well beyond 110 GHz. It features a 0.67-W power consumption, resulting in a 1.5-GBd FoM with good output signal quality. To the best of our knowledge this linear driver shows the highest >64 GBd PAM-4 performance in current state-of-the-art, without DSP nor pre-emphasis. We also report on a newly developed 0.5-μm InP DHBT technology and its modelling using small-value external parasitic EM-simulation extraction, showing improved high-frequency prediction accuracy at circuit level.