Gencoa currently use both 2D and 3D finite element modelling packages to create magnetic field designs specific to customer requirements. Factors that are taken into consideration include magnetron size and type, target material, target thickness, process requirements and any ferromagnetic components that may be present in the vacuum chamber. Once the magnetic array has been designed, a magnetic field picture is generated from which valuable information can be gained such as magnetic field strength and shape, level of balance and erosion points. This information is then used to optimize, for example, target erosion, coating uniformity, anode position, substrate position and substrate bombardment.

The use of 3D magnetic simulation is essential due to the complex nature of some of the Gencoa magnetic designs. The standard magnetics are a simple 2 pole design, seen above. The High Yield (HY) type magnetcs are a more complicated multi-pole system which controls the plasma better to improve target use. The rectangular and circular FFE type magnetron has a high speed scanning magnetic field which requires 3D time-resolved analysis to provide the 'picture' of the field and enable the design to be optimised.

Gencoa also simulate and design magnetic systems for other manufacturers cathodes. These can be magnetic packs to be retro-fitted into the existing magnetron to improve the performance of the product in terms of either target use or coating uniformity. Improvement in the design of magnetic packs for rotatable magnetrons to reduce the enhanced target erosion at the turn-around have been generated and can be supplied as a retro-fittable magnetic bar for any manufacturuers rotatable magnetron. The generation of the magnetic model is the first stage in the optimisation process. The data is then used to predict the plasma distribution and target erosion in 3D which enures the best possible target use.

Flow diagram showing the typical modelling procedure

In summary, FE modelling optimises magnetic field shape, magnetic field strength, level of balance/unbalance, system interaction and anode interaction.