Researchers at the Hong Kong University of Science and Technology (HKUST) have developed a new type of acoustic chip that can handle more than 12 times as much power as current designs while staying much cooler and more stable.
The breakthrough could help support future technologies such as 6G mobile networks, direct-to-cell satellite communications, quantum computing and advanced power electronics.
The new design, called the Layered Acoustic Wave (LAW) architecture, was tested using devices that vibrate more than two billion times every second.
During testing, the chip reduced temperature increases by 70% and achieved a record power-handling capability, overcoming a major limitation that has restricted acoustic chips for decades.
Although most people have never heard of them, acoustic wave chips are found in nearly every smartphone.
They convert radio signals into tiny sound waves that vibrate at extremely high frequencies, allowing devices to filter wireless signals accurately.
Because sound travels much more slowly than light, these chips can process high-frequency signals using very small components, making them essential for compact electronic devices.
As wireless technologies continue to evolve, these chips are expected to play an even bigger role. Future applications include 6G communications, direct satellite connections to smartphones, quantum information processing, microfluidic devices and energy-efficient power conversion systems.
However, acoustic chips have long struggled with high-power operation. When they are pushed too hard, the intense vibrations generate heat and mechanical stress inside the device.
This can cause metal atoms in the chip’s electrodes to shift position, a problem known as acoustomigration, eventually leading to electrical failure. The heat can also change the operating frequency and even crack the chip’s delicate materials.
Until now, engineers have mainly tried to solve these problems by improving the bottom of the chip with expensive materials that conduct heat better. However, this approach leaves heat trapped near the top surface, where the acoustic waves are actually generated.
The HKUST team took a completely different approach. Instead of leaving the top surface exposed to air, as conventional designs do, they covered it with carefully designed layers of silicon dioxide and amorphous silicon.
At first glance, this idea seemed risky because engineers had long believed the surface needed to remain open for the acoustic waves to function properly. However, computer simulations and experiments showed that the sound waves remained confined where they were needed while the new layers provided several important benefits.
The added material spread heat away from hot spots, greatly reducing operating temperatures. It also redistributed mechanical stress throughout the chip, cutting the peak stress responsible for acoustomigration to about one-quarter of previous levels. In addition, the design helped keep the chip’s operating frequency stable even as temperatures changed.
The improvements were dramatic. Under the same operating conditions, the new LAW chip warmed by only 5.2°C, compared with 17.4°C for a leading conventional device. It also withstood more than 12 times higher power before failing. Detailed analysis showed that while conventional chips developed damaged electrodes and cracked materials, the new design showed no comparable signs of failure.
Because the new architecture relies on a simple, low-cost manufacturing process rather than expensive materials, the researchers believe it could be widely adopted.
They expect the technology to support future high-performance radio filters, direct-to-cell satellite services, 6G wireless networks, quantum acoustic systems and other advanced electronic devices that require compact components capable of handling much higher power.
The study was published in Nature Communications.
