Real-Time Plasma Probe Measurement to Monitor Plasma Processes

A German University start-up has developed an innovative measuring probe for low pressure plasma processes (e.g. CVD, PVD). The problem with these surface-activating plasma processes is that they have to be carried out in difficult-to-access vacuum chambers/reactors. This makes proper monitoring of these processes challenging. Currently, most of the process parameters are monitored through sensors fitted to the wall of the reactor, which is only in the periphery of the actual plasma process and therefore less accurate.

The proposed probe design enables real-time and accurate measurement of most relevant process parameters in-situ. It can be flexibly positioned within the reactor without affecting the process. Their technology has been extensively tested and fine-tuned over the last few years and is now ready to be used in industrial processes.

The German startup is seeking industrial partners interested in technological cooperation agreements who want to improve their plasma process outcomes, quality and efficiency by developing and adapting the MRP technique to their specific needs. The company is also interested in financial agreement with investors in order to secure future developments and products.

Plasma processes, used in many industrial fields to modify, clean and coat surfaces, are very sensitive and require precise monitoring. However, plasma processes usually take place under low pressure or in a vacuum, which means that they have to be carried out in a difficult-to-access vacuum chamber. Current techniques and sensors only allow measurement at the periphery of the process, such as through sensors fitted in the vacuum chamber´s wall. These peripheral measurements only give access to indirect process values (voltages, light emission or coating weight) and not to the actual process values.

A German start-up has developed the Multipole Resonance Probe (MRP), that enables measurement in the inner plasma process itself. The probe is able to measure critical process values such as electron density, temperature and collision frequency. The probe is mounted either inside the vacuum chamber interior space or at the chamber wall and stands in the plasma bulk. In most applications, it is possible to position the probe to prevent any disturbance or shadowing of the plasma process. The use of a planar system can also be considered where it is integrated in the wall.

The innovative Multipole Resonance Probe (MRP) enables the accurate measurement of plasma processes in otherwise difficult environments. In turn, this allows for the greater efficiency, results and quality of plasma processes such as dielectric coating processes. The technology has been extensively tested and fine-tuned over the last years and is now ready to be used in industrial processes.

The Multipole Resonance Probe (MRP) technique offers the following benefits:

• Robust
• Simple to mount and install in existing setups
• Easy to position (very flexible)
• More cost-efficient compared with current solutions
• No or limited interference in the plasma process
• Increases the process quality as well as throughput
• Makes plasma processes faster and more efficient
• Easy to evaluate
• High-temperature resistant
• Especially suitable for dielectric coating processes