TECH

New X-ray vision for electronics lets scientists monitor working chips remotely

A groundbreaking advancement is reshaping how scientists observe the inner workings of electronic chips—ushering in a new era where semiconductor devices can be monitored in real-time without physical interference or shutdowns. This revolutionary technique leverages terahertz (THz) waves—an emerging, safe form of electromagnetic radiation—to non-invasively detect the minute electrical changes inside fully operational, sealed semiconductor components. The implications for electronics engineering, security, and safety-critical systems are profound, potentially transforming chip diagnostics and quality control across diverse industries.

Traditional methods for inspecting semiconductor devices demand either direct physical contact using electrical probes, dismantling of chip packaging, or device deactivation. These approaches are inherently intrusive, disruptive, and often impractical in real-world, high-stakes scenarios. Now, an international coalition of researchers, spearheaded by Adelaide University’s Terahertz Engineering Laboratory under Professor Withawat Withayachumnankul, have demonstrated a pioneering method that overcomes these hurdles. By employing terahertz waves, they monitor electrical activity deep within chips in real-time, even as the devices operate under full load.

A team of international researchers have developed a breakthrough way to observe what is happening inside electronic chips while they are operating—without touching them, taking them apart, or switching them off. The new technique uses terahertz waves, a safe and non-ionizing form of electromagnetic radiation, to detect tiny movements of electrical charge inside fully packaged semiconductor devices. For the first time, this allows scientists and engineers to monitor electronic components as they function in the real world.

The study, published in the IEEE Journal of Microwaves, involves researchers from Adelaide University in Australia, US technology company Virginia Diodes Inc, the Hasso Plattner Institute and the University of Potsdam, Germany.

Adelaide University Group Leader of the Terahertz Engineering Laboratory (TEL), Professor Withawat Withayachumnankul, said that semiconductors underpin almost every modern technology, from smartphones and medical devices to vehicles, power grids and defense systems.

"Yet once a chip is sealed inside its protective packaging, it becomes extremely difficult to tell what is happening inside it," Prof Withayachumnankul said.

"Most existing inspection methods require physical electrical probes, exposed chips, or devices to be powered down—making them impractical in many scenarios.

"This research is a first step towards a long-standing problem in electronics. We can now observe electrical activity inside a working semiconductor device from the outside, without damaging it or interrupting its operation."

Image generated by AI, demonstrating how the new technique using terahertz waves works. Credit: Adelaide University

The study demonstrates that terahertz waves can non-invasively detect changes in electric current inside common electronic components such as diodes and transistors.

The method is sensitive enough to pick up changes occurring in regions far smaller than the terahertz wavelength itself, something previously thought to be impractical due to fundamental noise limits.

To achieve this, the researchers developed an ultra-sensitive detection system using a specialized homodyne quadrature receiver, which can pick up very small changes in terahertz signals.

"This approach allows the system to cancel out background noise and isolate the faint signal produced by electrical activity inside the device," Prof Withayachumnankul said.

"The result is a real-time view of electronics at work, even when the active region is buried deep inside sealed packaging."

The researchers say that the signals they observed were caused by genuine electrical motion, not heat or electronic interference. The technique was shown to work across a range of commonly used semiconductor components, demonstrating its robustness and broad relevance.

The implications for society and industry are significant, Prof Withayachumnankul said.

"Because terahertz radiation is non-ionizing and safe, the technique also offers a safer alternative to inspection methods that rely on X-rays or invasive probing.

"This makes it particularly attractive for safety-critical applications, such as high-power electronics, where devices cannot easily be taken offline."

The work could also benefit the security and defense sectors.

"Being able to remotely and non-invasively assess electronic activity could help verify the integrity of critical hardware, detect malfunctioning or compromised components, and monitor systems where physical access is limited or undesirable," according to lead investigator Dr. Chitchanok Chuengsatiansup, Professor of Cybersecurity at the Hasso Plattner Institute and the University of Potsdam.

"This research opens the door to smarter, self-diagnosing electronics, new ways of monitoring complex integrated circuits, and faster development of next-generation chips."

Provided by University of Adelaide