RF source care – antenna

We do a lot of cleaning and repair service at Plasma Process Group and we let a good chance to see your hardware throughout its life cycle. For the same reason, we also get to see what causes that life cycle to shorten. Here are a few quick things you can do or keep in mind to get the most out of your hardware:

A fresh RF antenna is coated with silver that improves the RF conductivity, and therefore efficiency, of the RF ion source. Over time, this silver coating will tarnish (oxidize) or erode. While the antenna will continue to work, the performance will decline slightly. Additionally, the antenna can gather debris on its surface that needs to be cleaned to prevent arcing. About once every 2 – 3 months, during a vent cycle, take a Kimwipe or other gentle cleaning cloth and wipe the coils of the antenna clean. When doing this, it is important to not push the debris into contact with the insulators holding the antenna. If the antenna has lost all of its silver coating, showing the bare copper underneath, it can be replaced entirely to maintain the performance of the ion source.

The insulators which hold the RF antenna in place may need occasional cleaning. New insulators are either pure white, or have a slight yellow tint to them. As they are exposed to debris, heat, and small amounts of plasma, they will discolor, turning copper brown or black. To clean them, remove one pair at a time and media blast them, followed by an ultrasonic bath and an isopropyl alcohol wipedown. Then reinstall that pair before removing the next. This will prevent inadvertent changes to the antenna positioning.