Fraunhofer IAF reveals novel bidirectional GaN switches
At the upcoming PCIM Conference (6th - 8th May, Nuremberg, Germany) Fraunhofer IAF will present a paper on a novel GaN monolithic bidirectional switch (MBDS) suitable for the 1200 V voltage class with integrated free-wheeling diode. This is one a number of innovations to be shown at PCIM by the research institute.
The 1220V device was built using Fraunhofer IAF's GaN-on-insulator technology. The MBDS blocks voltage and conducts current in two directions, which saves chip space and reduces conduction losses as there is only one split depletion region. The GaN MBDS can be used in grid-connected power converters for energy generation and storage as well as electric drive systems. In these applications, the MBDS enables the development of systems in the 1200 V class.
Fraunhofer IAF has also made progress in the field of multi-level converters with bidirectional switches for blocking voltages up to 48 V. Researchers have used a conventional single-gate HEMT based on AlGaN/GaN in a low-voltage 3-level T-type converter as a bidirectional switch. This achieves simpler control of the transistor than with a bidirectional transistor with two gates for such topologies.
Like the 1200 V MBDS, this innovative approach enables simpler control in addition to a space-efficient component design.
Daniel Grieshaber will present the results at PCIM on May 6, in his paper 'Investigation of a Single-Gate GaN HEMT as Bidirectional Switch in a Low Voltage Multilevel Topology' at a poster session from 3:30 to 5:00 pm.
GaN power electronics portfolio
In addition to innovations in the field of bidirectional switches, researchers at Fraunhofer IAF are working along the entire semiconductor value chain on materials, components, modules and subsystems for GaN-based power electronics in the voltage classes 48 V, 100 V, 200 V, 600 V and 1200 V.
The current focus is on lateral and vertical components, monolithic integration, and highly insulating substrates such as sapphire or SiC. In addition to the results presented at PCIM 2025, Fraunhofer IAF is already working on components in the 1700 V class.
Fraunhofer IAF will be presenting an overview of its research and development portfolio in power electronics on it stand at the PCIM Expo. It will show an epitaxial 8-inch GaN wafer, processed 4-inch GaN-on-SiC and GaN-on-sapphire wafers, GaN power ICs, integrated lateral and vertical GaN components and 600 V half-bridge modules based on GaN.
At the PCIM Conference, Richard Reiner will also summarise the latest power electronics developments at Fraunhofer IAF in his presentation 'Lateral, Vertical, Bidirectional! Innovations and Progress in GaN Devices and Power ICs' on May 7 from 10:50 to 11:10 a.m. on the Technology Stage.
