Gas Connections on  Externally Mounted Magnetrons

As an option on all Gencoa magnetrons an integral gas distribution can be included. The gas is connected to the rear of the magnetron and then distributed uniformly in the side and anode wall before being ejected from the front of the anode. No more space is required, and it is a convenient method to ensure good uniformity for both reactive and non-reactive processes. 

Magnetrons that are externally flange mounted with a rear safety shield will have the gas input of the shield wall. If an MFC is used for fast gas feedback via Speedflo, this will be located inside the rear shield, downstream of the gas connection.

Cantilever mounted magnetrons will contain the gas connections on the rear of the bulkhead flange. The number of connections will be determine by the type of reactive gas control to be used. Common methods for double magnetrons are 1:1:1. 1:3:1 & 1:5:1. The central number in the group of 3 defines the number of fast feedback trimming zones there are along the cathode length.

Gas Connections on  Internally Mounted Magnetrons

For internal magnetrons with customer supplied support and connections, the gas points will be on the cathode rear. The position of the input to gas anode will be fixed, but the connection point to the supply can be specified by the customer. For fast feedback reactive gas control, the supply MFC should be as close as possible to the cathode - on the chamber wall ideally.

The number of gas connections can be defined in consultation with Gencoa. For non-reactive processes, multiple gas connections can be used to tune uniformity via argon gas delivery (with the addition of small amounts of reactive gas). For reactive systems with feedback control, the argon is a constant flow and the reactive gas such as O₂ is controlled by the Speedflo unit. For larger cathode (>0.75m) it is common that the reactive gas element is split into zones, to ensure both a fast feedback and also the possibility to 'tune' the uniformity of the coating by controlling each zone differently.