Fraunhofer team develops InGaAs-on-Si broadband amplifier
Researchers at Fraunhofer IAF have developed a broadband distributed amplifier chip based on the institute’s proprietary InGaAs-on-Si HEMT technology. It achieves a gain of 11 ± 2 dB between 4 and 420 GHz and is suited for use in data centres, measurement systems and sensors. Along with other new developments in the field of high-frequency electronics, Fraunhofer IAF will present the chip from October 4 to 9, 2026, at European Microwave Week in London.
Modern data centres, high-precision measurement systems and high-resolution radar sensors rely on extremely broadband amplifier chips that feature both low noise and high output power. Researchers at the Fraunhofer Institute for Applied Solid State Physics IAF have developed a monolithic microwave integrated circuit (MMIC) with outstanding performance in these areas.
The distributed amplifier (DA) achieves a gain of 11 ± 2 dB in the frequency range between 4 and 420 GHz. It is based on high-electron-mobility transistors (HEMTs) fabricated in the InGaAs-on-Si material system with a gate length of 20 nm. Previous generations of the chips were still fabricated on GaAs substrates with a gate length of 35 nm.
The MMIC was first presented in the article: F. Thome and A. Leuther, 'A 4–420-GHz Distributed Amplifier MMIC in a 20-nm InGaAs-on-Si HEMT Technology With 11 ± 2 dB Gain,' in IEEE Microwave and Wireless Technology Letters, vol. 35, no. 6, pp. 844–847, June 2025, doi: 10.1109/LMWT.2025.3551639.
“The MMIC amplifier we developed is characterised by a unique combination of the relevant parameters: bandwidth, noise and output power. Up to a frequency of 202 GHz, it achieves noise figures between 3.2 and 7.7 dB; in a setting optimised for low noise, these range from 2.8 to 6.7 dB. The saturated output power ranges between 6 and 8 dBm,” explains Fabian Thome, developer of the MMIC and deputy head of the High-Frequency Electronics Business Unit at Fraunhofer IAF.
Such high-bandwidth amplifiers are particularly relevant for the latest generation of data centres that use optical data transmission. They are used in interfaces where optical signals are converted to electrical signals or electrical signals are converted to optical signals. Optical data transmission enables higher speeds and more compact designs. The increasing prevalence of artificial intelligence applications is driving a massive rise in demand for modern data centres.
In addition, high-bandwidth chips with low noise and high output power enable significantly more precise measurement systems and higher-resolution radar sensors. Higher-performance chips significantly increase the resolution, range and sensitivity of these systems.
Fraunhofer IAF at EuMW 2026
At European Microwave Week (EuMW), taking place in in London from October 4 to 9, 2026, Fraunhofer IAF researchers will present exhibition samples of the amplifier chip as well as other innovations in high-frequency electronics at Booth B35. FormFactor, Inc., a collaborating measurement technology manufacturer, will demonstrate a live measurement of the chip at its booth .
