IEEE Spectrum – Semiconductors

Terahertz Waves Spy on a Chip’s Internal Activity

Researchers at Adelaide University demonstrated a terahertz‑based system that can remotely monitor the electrical activity of transistors inside packaged chips. The setup uses a vector network analyzer, a terahertz frequency extender, and a homodyne quadrature receiver to detect minute changes in amplitude and phase reflected from the chip. Experiments successfully tracked switching in bipolar junction transistors and field‑effect transistors within a 1 mm² spot, all without removing the package. The approach is still early‑stage but could eventually replace invasive probing and X‑ray inspection for certain applications.