Modern data centers, 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 indium gallium arsenide (InGaAs) on silicon (InGaAs-on-Si) material system with a gate length of 20 nm. Previous generations of the chips were still fabricated on gallium arsenide (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 .
High bandwidth with high output power and low noise
"The MMIC amplifier we developed is characterized 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 optimized for low noise, these range from 2.8 to 6.7 dB. The saturated output power ranges between 6 and 8 dBm," explains Dr. Fabian Thome, developer of the MMIC and Deputy Head of the High-Frequency Electronics Business Unit at Fraunhofer IAF.
Broadband MMICs in practice: data centers, measurement systems, radar sensors
Such high-bandwidth amplifiers are particularly relevant for the latest generation of data centers 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 centers.
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 (D10).
Researchers from Fraunhofer IAF will also present their latest findings as part of the EuMW conferences:
- October 5, 2026, 8:30 a.m.–6:30 p.m., Room 15, WM06 [Workshop]
Fabian Thome: InGaAs Metamorphic HEMT Technologies for Cutting-Edge Low-Noise, High-Frequency, and Ultra-Wideband Applications
- October 5, 2026, 9:10–9:30, Room 10, EuMIC02-3
Maxime Moulin: Scalable Small-Signal Modeling of 20-nm InGaAs HEMTs Using a DC-Biased Backside Field Plate
- October 5, 2026, 5:30–5:50 p.m., Room 11, EuMIC12-3
Eric Sigle: Extended D-Band Frequency Quadrupler Based on Harmonic Source- and Load-Pull Measurements
- October 6, 2026, 9:50–10:10, Room 17, EuMIC15-5
Rainer Weber: A 220 to 330 GHz Dual-IF Receiver Chip in 35-nm mHEMT Technology
- October 6, 2026, 11:50–12:10, Room 17, EuMIC17-3
Patrick Umbach: Zero-IF Capable Single-Balanced HEMT Mixers with 2 ± 2 dB Conversion Loss from 110 to 220 GHz
- October 6, 2026, 3:10–3:30 p.m., Room 17, EuMIC18-4
Felix Heinz: Extended W-band Low-Noise Amplifiers in 35-nm Metamorphic High-Electron-Mobility Transistor Technology
- October 6, 2026, 3:30–3:50 p.m., Room 17, EuMIC18-5
Thomas Zieciak: A Compact D-Band GaN LNA MMIC for Monolithic Transceiver Integration
- October 7, 2026, 6:10–6:30 p.m., Room 7, EuMC35-5
Daje Weber-Trebesch: A Q-Band GaN Doherty-Like OLMBA with Single RF Input
About Fraunhofer IAF
The Fraunhofer Institute for Applied Solid State Physics IAF is one of the world's leading research institutions in the fields of III-V semiconductors and synthetic diamond. Based on these materials, Fraunhofer IAF develops components for future-oriented technologies, such as electronic circuits for innovative communication and mobility solutions, laser systems for real-time spectroscopy, novel hardware components for quantum computing as well as quantum sensors for industrial applications. With its research and development, the Freiburg research institute covers the entire value chain — from materials research, design and processing to modules, systems and demonstrators. https://www.iaf.fraunhofer.de/en.html
Further information
https://www.iaf.fraunhofer.de/en/customers/electronic-circuits.html – Overview of Fraunhofer IAF research activities in the field of electronics
https://www.iaf.fraunhofer.de/en/events/eumw.html – Fraunhofer IAF at EuMW 2026
https://www.iaf.fraunhofer.de/en/networkers.html – How to collaborate with Fraunhofer IAF
