The thinnest GaN chiplet in the world was made by Intel: 19 micrometers on 300 mm wafers
Intel Foundry has developed a chiplet based on gallium nitride (GaN) that aims to overcome some of the structural limits of silicon in high power and frequency applications. Engineers from the Santa Clara company have packaged a chiplet with a substrate reduced to just 19 micrometers, obtained from 300 mm GaN-on-silicon wafers, and equipped with integrated digital circuits directly on the same die.
The work was presented at the IEEE International Electron Devices Meeting 2025 and represents a significant evolution in chiplet architectures, where the separation between power components and digital logic has so far imposed trade-offs in terms of efficiency and design complexity.
One of the most distinctive elements of the research is the integration of GaN transistors for power management with PMOS silicon transistors dedicated to digital logic. This approach eliminates the need for separate chiplets for control, reducing energy losses due to interconnection between distinct components.
The process leverages layer transfer techniques to place silicon directly on the GaN wafer, allowing for the realization of complete logic circuits - inverters, NAND gates, flip-flops, and ring oscillators - with switching times on the order of 33 picoseconds and uniformity across the 300 mm surface.
The reduction in thickness to 19 μm was achieved using a technique called "stealth dicing before grinding" (SDBG), which employs internal laser scribing followed by mechanical thinning. The result is an extremely thin chiplet without compromising the integrity of the active structures.
Electrical measurements indicate high performance: transistors with a 30 nm gate can handle voltages up to 78 V, maintaining low losses and supporting operating frequencies above 300 GHz, values compatible with advanced RF applications.
Gallium nitride is a wide-bandgap semiconductor, characterized by greater efficiency in handling high voltages, superior switching speeds, and lower energy losses compared to silicon. Additionally, its ability to operate at higher temperatures makes it suitable for scenarios where thermal dissipation represents a critical constraint.
The adoption of 300 mm wafers compatible with existing infrastructures represents an additional strategic element, as it allows for potential industrial scalability without requiring radical investments in new production lines.
The expected applications range from data centers to telecommunications infrastructures. In server systems, GaN chiplets of this type can improve the efficiency of voltage regulators, bringing them physically closer to processors and reducing resistive losses.
In the wireless sector, high-frequency performance - over 200 GHz - makes this technology particularly interesting for RF frontends intended for advanced 5G networks and future 6G implementations, as well as for radar, satellite communications, and photonics.
Intel has subjected the devices to standard reliability tests, including TDDB, pBTI, HTRB, and HCI, achieving results consistent with the requirements for real-world use. This aspect is crucial for the transition from laboratory demonstration to industrial product.