Han_Wui_Then
Employee
04-07-2026
Han Wui Then is a senior principal engineer at Intel Foundry Technology Research specializing in advanced semiconductor materials and advanced transistor development. Co-authors include Samuel Bader, Ahmad Zubair, Heli Vora, Prafful Golani, Pratik Koirala, Michael Beumer, Trianggono Widodo, Aris Orbase, Patrick McIllece, Andrey Vyatskikh, Thomas Hoff, Rambert Nahm, Kirby Maxey, Dimitri Frolov, Isha Khandelwal, Shreyas Jayaprakash, Kaushik Narayanan, Jag Rangaswamy, and Marko Radosavljevic from Intel Foundry Technology Research.
Highlights
- Intel Foundry has created the world's thinnest gallium nitride (GaN) chiplet — its base silicon measuring just 19 micrometers (μm) thick — harvested from a 300 millimeter (mm) GaN-on-silicon wafer.¹
- Researchers have successfully combined GaN transistors with traditional silicon-based digital circuits on a single chip, allowing complex computing functions to be built directly into power chiplets without needing separate companion chiplets.
- Rigorous testing confirms that this new GaN chiplet technology is a promising candidate that can meet the reliability standards required for real-world deployment — enabling smaller, more efficient electronics for applications ranging from data centers to next-generation 5G and 6G communications.
The demand for this innovation stems from a fundamental tension in modern electronics: the need to pack more capability into tighter spaces while simultaneously handling higher power loads and faster data speeds. Traditional silicon-based technologies are approaching their physical limits, and the industry has been looking to alternative materials like GaN to bridge the gap. Intel Foundry combines the ultra-thin GaN chiplet with on-die digital control circuits — eliminating the need for a separate companion chiplet and reducing the energy lost routing signals between components. Comprehensive reliability testing further demonstrates that this platform is a promising candidate for a real-world product.
This technology opens the door to concrete improvements across several industries. In data centers, GaN chiplets could switch faster, losing less energy than silicon alternatives. This would enable voltage regulators that are smaller, more efficient, and positioned closer to the processor — reducing the resistive energy losses that occur over long power routing paths. In wireless infrastructure, the high-frequency performance of GaN transistors makes it a natural candidate for radio frequency (RF) frontend technology such as base stations used in 5G and 6G systems being developed for the next decade. GaN's ability to operate efficiently at frequencies exceeding 200 GHz positions it well for the centimeter- and millimeter-wave bands on which next-generation networks will rely.¹ Beyond networks, the same capabilities are relevant to radar systems, satellite communications, and photonic applications where fast electrical switching is needed to modulate light signals.
Why GaN? Understanding the Material Advantage
Gallium nitride is a compound semiconductor — a material made from two elements — that has attracted enormous attention because of its exceptional physical properties. Think of a semiconductor transistor as an electrical valve or switch that controls the flow of electricity. Silicon, the material used in most transistor chips today, is a good valve but has limits: it struggles at high voltages and generates more heat and energy loss as switching speeds increase. GaN transistors can handle much higher voltages, switch far faster, and lose significantly less energy in the process. This makes it particularly attractive for power conversion — the process of stepping voltage up or down efficiently.Intel Foundry's approach — growing GaN on large silicon wafers at the industry-standard 300 mm diameter — allows GaN chiplets to be made using much of the same infrastructure already built for conventional silicon, potentially reducing cost dramatically and enabling the high-volume production the industry requires.
A Novel Approach: Building the World's Thinnest GaN Chiplet
Thinning a semiconductor wafer sounds straightforward, but doing it on a fully processed 300 mm GaN-on-silicon wafer — one that already contains all the transistors and metal wiring layers — without damaging those structures is a formidable engineering challenge. The Intel Foundry team accomplished this using a technique called stealth dicing before grinding (SDBG), which uses a precisely controlled laser to create microscopic fracture lines inside the wafer before a mechanical grinding step reduces its thickness. The result is a GaN chiplet with an underlying silicon base of just 19 μm.
Figure 1. Electron microscope images of the harvested GaN chiplet showing the ultra-thin 19 μm silicon substrate beneath the fully processed chiplet stack. Figure 1 (d) shows a prototype with a GaN chiplet flipped and attached to a base wafer, illustrating how the technology fits into real chiplet assembly.
To verify that thinning the wafer did not compromise performance, the team measured the electrical characteristics of transistors on the harvested chiplets. Transistors with gate lengths as short as 30 nanometers (nm) demonstrated excellent current carrying capability, low energy loss, and the ability to block voltages up to 78 volts. The RF performance was equally strong, with transistors achieving operating cut-off frequencies exceeding 300 GHz — well into the range needed for next-generation wireless communications.¹
Compared to traditional CMOS-based silicon chips, GaN chiplets offer a compelling combination of advantages that silicon simply cannot match at its physical limits. GaN delivers higher power density, enabling more capable systems in smaller footprints — a critical advantage in space-constrained applications such as point-of-load power delivery for data centers, electric vehicles (essentially a data center on wheels), and wireless base stations. Silicon becomes unreliable at junction temperatures above approximately 150°C, which limits its use in high-heat environments. GaN's wider bandgap potentially allows it to operate at higher temperatures with greater stability, reducing power losses during switching, and enabling more efficient thermal management, which in turn reduces the size and cost of cooling systems. In addition, Intel Foundry's use of standard 300 mm silicon wafers for GaN production is compatible with current silicon-based manufacturing infrastructure, promising to reduce the requirement for major new investments.
Integrating Silicon Logic Directly onto the GaN Chiplet
Perhaps the most novel aspect of this work is the demonstration of fully functional digital circuits built directly onto the GaN chiplet itself. In conventional electronics, digital control logic — the circuitry that tells a power transistor when to switch on and off — is typically handled by a separate silicon chip.In a chiplet-based system, that separate chip takes up precious space and introduces inefficiencies from the longer electrical pathways between components. The Intel Foundry team offers a potential solution to solve this by combining two types of transistors on the same chiplet: GaN N-channel metal-oxide-semiconductor high-electron-mobility transistors (N-MOSHEMT), which excel at handling power (high voltages), and silicon p-channel metal-oxide-semiconductor field-effect (Si PMOS) transistors, which are well-suited for lower-voltage digital logic. By transferring silicon onto the GaN wafer through a process called layer transfer, both transistor types can be built side-by-side and connected using the same wiring layers.
Figure 2. A cross-sectional electron microscope image showing a GaN power transistor and a silicon logic transistor built side-by-side on the same 300 mm GaN-on-silicon wafer.
Using this combined process, the team built and tested a complete library of digital circuit building blocks: inverters (which flip a signal from on to off), NAND gates (a fundamental logic operation), multiplexers (circuits that select between multiple input signals), flip-flops (circuits that store a single bit of information), and ring oscillators (chains of inverters used to measure circuit speed). Every circuit worked correctly, and the speed measurements — with each inverter switching in just 33 picoseconds (ps) or 33 trillionths of a second — were consistent across the entire 300 mm wafer, confirming that the process is uniform and potentially manufacturable at scale.¹
Proving Reliability: Built to Last
Demonstrating that a new semiconductor technology works in the lab is only half the battle. Before any chiplet technology reaches real products, it must prove it can operate reliably for years under the stresses of real-world use — heat, high voltages, and sustained electrical current. The Intel Foundry team subjected the GaN transistors to four industry-standard reliability tests, each designed to simulate a different type of stress that chiplets encounter over their lifetime. Promising results in time-dependent dielectric breakdown (TDDB), positive bias temperature instability (pBTI), high-temperature reverse bias (HTRB), and hot-carrier injection (HCI) studies indicate that the 300 mm GaN MOSHEMT technology can meet required reliability metrics.What's Next?
Integrating digital control circuits directly onto GaN power chiplets opens the potential for increasingly sophisticated on-die intelligent chiplets, high‑speed switching, and efficient power conversion in a compact form factor. As the semiconductor industry continues its transition toward chiplet-based architecture, Intel Foundry's 300 mm GaN-on-silicon platform is well-positioned to play a central role in delivering the performance, efficiency, and density that the next generation of computing and communications systems will demand. From hyperscale operators to next-generation wireless networks to defense platforms and satellite communications systems, GaN's efficiency compounds into substantial reductions in electricity costs, cooling infrastructure, and carbon emissions — directly addressing the most pressing challenges in many industries.Want to learn more about Intel Foundry’s chiplet-based solutions? Reach out to us at intel.com/foundry and foundry.contact@intel.com.