The Enhanced Field System (EFS)
for plasma control in PVD processes

Gencoa has developed and patented worldwide a technique for controlling the amount of ion bombardment in small or large scale magnetron sputtering systems. The Enhanced Field System or EFS is a very simple method of controlling and varying the amount of ionisation in a vacuum chamber. The method relies upon magnetic attraction or repulsion of the plasma electrons that emanate from magnetron sources.

Low Density Plasma Effects	High Density Plasma Effects
Enlarge	Enlarge

The EFS system is a central electrode that contains permanent magnets that can rotate to change the magnets polarity with respect to the facing magnetron(s). The polarity of the central magnet changes the overall magnetic field map of the process chamber and will either prevent or allow the electrons in the chamber reaching earth potential.
If the electrons are allowed to reach earth, then they are very quickly lost to the plasma and the number ions they create will be very low. If however the EFS system is used to preserve the electrons, they will create many ions that can then be used for ion assistance of the deposition process.

Hence the EFS system can very easily vary the ion bombardment from low to very high levels and can also achieve any intermediate setting. This can be done at different points during the process to optimise all the processes stages from pre-cleaning to bulk film deposition. Alternatively, the magnets can be continuously rotated to modulate the properties of the film structure.

Additionally the EFS unit can be earthed, electrically floating, or biased positive or negative (with or without pulsing) to give further control or enhancement of the electron motion.

All the magnetrons in a process chamber can interact in different ways with the EFS unit if required, so one material can be deposited with low bombardment whilst the other material is simultaneously deposited with high bombardment.
Since all the magnetrons are the same polarity, there is no 'cross-talk' between magnetrons that has previously prevented large chamber magnetron processes from creating enough ionisation for high bombardment processes. So the EFS unit can be used to create very large scale magnetron based optical, hard or decorative coating machines.

A good example of the flexibility of the EFS unit is for low friction coatings which are not deposited under high bombardment conditions since this increases stress in the coatings. However, the parts loaded into the chamber still require an aggressive plasma pre-clean and high bombardment at the start of the coating process for good adhesion. Later in the process the ion bombardment is reduced to a pre-defined level to optimise the bulk film structure. Hence the EFS can create both sets of conditions very easily to optimise the adhesion and bulk layer properties.

View coatings examples with EFS

Gencoa is a highly successful manufacturer of magnetron sputter sources and is also very active in process development. Gencoa does not aim to manufacture complete deposition equipment or provide a coating service, hence the need to make partnerships with such companies to effectively exploit the EFS technology.

Gencoa is hence seeking partners that would like to use the EFS technology and the patent rights. The agreement can be made on a global scale or can be done on a country or regional basis. The terms are flexible and can be exclusive or non-exclusive depending upon the needs of the potential user.
If you have an interest in exploiting this technology then please contact Dr Dermot Monaghan using the Contact form.

In addition to the EFS technology Gencoa can provide all the necessary support for the implementation of a wide range of processes to either a production coating company or a commercial equipment manufacturer.