- CEA-Leti has created a GaN/Si process technology compatible with CMOS cleanrooms. It offers high performance of semiconductor material and is less expensive than existing GaN/SiC technologies.
- The new technology was designed for applications such as 5G/6G infrastructure, radar for UAV detection, and earth observation. Testing on the process technology has started, with a focus on boosting device performance and increasing operation frequency toward 100+ GHz.
CEA-Leti, a technology research organization, has developed a 200 mm gallium nitride/silicon (GaN/Si) process technology. Unique to this technology is its compatibility with complementary metal-oxide-semiconductor (CMOS) cleanrooms. This maintains the high performance of the semiconductor material, with less cost than the existing gallium nitride/silicon carbide (GaN/SiC) technologies.
This development was shared by the institute at the International Electron Devices Meeting (IEDM) 2023. Here it was explained how the current GaN high-electron-mobility-transistor (HEMT) technologies, used in telecom or radar applications, rely on small GaN/SiC substrates. The latter requires processing in dedicated cleanrooms. The SiC substrates used for growing GaN layers are quite expensive and only available in a relatively small size.
Addressing these constraints, CEA-Leti’s project developed GaN/Si on 200 mm, with prospects for 300 mm wafer diameters. Doing so in CMOS-compatible cleanrooms can reduce substrate cost and leverage already existing high-performance cleanroom facilities.
In effect, CEA-Leti’s GaN/Si technology performance at 28 GHz began gaining ground against GaN/SiC technology in terms of power density. According to Erwan Morvan, CEA-Leti scientist, the goal was to reach the existing state-of-the-art GaN HEMT performance at ~30 GHz with a 200 mm CMOS-compatible GaN/Si technology and to compete with GaN/SiC technology.
Morvan reinforced how the developed technology demonstrated that the 200 mm SiN/AlN/GaN MIS-HEMT on silicon technology is a promising candidate for applications like 5G/6G infrastructure, satcom, radar for UAV detection and earth observation. Devices conceived from the project can be used in applications around 30 GHz frequency while ensuring high power density, high efficiency, lightweight, and compactness.
CEA-Leti’s ongoing R&D in this domain will include increasing the raw output power and efficiency of its MIS-HEMT transistors, integrating its improved process modules to enhance device performance, increase operation frequency toward 100+ GHz, and 3D integration of GaN/Si chips on 300mm Si wafers.’,