Transforming Leak Detection in Vacuum Coating Systems with Remote Plasma Optical Emission Spectroscopy
November 18, 2025 12:00 am
In this study, we introduce an alternative leak detection method based on remote plasma optical emission spectroscopy (RPOES). The technique exploits plasma-induced light emission to detect leaks in real time, enabling both detection and localisation using trace gases such as argon that are relatively inexpensive and readily available. Compared with mass-filter helium detectors, RPOES provides greater robustness, the ability to operate at higher pressures, and reduced maintenance demands. We outline the principles of RPOES, emphasise its advantages in detecting gases commonly linked to vacuum leaks (including water vapor and air), and assess its viability as a practical alternative to helium-based methods. Case studies are presented to demonstrate its effectiveness in identifying leaks across a range of coating applications, with ultimate aim to improved process stability, enhanced coating quality, and lower operational costs.