July 2017 newsletter

Ion Times

Powering Your Process

If you’re struggling with failing power supplies in your Ion Beam process, Plasma Process Group can help! Our I-Beam 703 can replace the whole batch of RF2001 power supplies you are likely already using for your RF sources, and our I-Beam 600-series can replace your older MPS power supply for your DC ion sources. Best, these I-Beam supplies come with proven reliability plus the excellent service and support you should expect from us.

Making Grids

In the last few months, we have been inundated with orders for new ion source grids. You may have noticed our lead times have extended. In order to help you, we are pleased to announce the acquisition of another CNC milling center to help resolve this backup. Scheduled to be up and running in the next two months, we hope we will be able to handle large orders of grids without adding a several week delay to smaller orders! This additional CNC capacity will also help us process orders for graphite or custom grids faster.

Target: Neutralized

Lurking behind every RF ion source, shrouded by … the shroud… is a little-known and poorly understood device that holds the success of your entire process in its tiny little … orifice. A well-functioning RFN goes unnoticed because everything works as it is expected to, but a struggling RFN can cause a wide range of problems such as ion beam instability ion source failure, and even complete process failure. A better understanding of your RFNcan help keep these catastrophic problems from becoming a … catastrophic problem.

RF Neutralizer
RF Neutralizer Brochure
RFN Flanges
RFN Flanges

RFNs come in one size, but many different configurations. They can be installed on any flange that allows all three leads to pass through to the Matching Network. In practice, this means any flange equal to or greater in size than a 2.75-inch Conflat. The most common flanges are the 2.75-inch and 6-inch Conflat. The emission from the RFN will couple with the ion beam as long as the electrons can easily reach the ion beam without interference fromother objects in the chamber. The RFN does not need to point directly at the beam! It is important that a ground-potential surface not be too close to the RFN, since the electrons will happily go there if the beam is much further away. However, it is also critical that there be good ground-potential surfaces in the chamber, since there will always be more electrons than ions!

Chambers with heavily coated liners often see unusual effects from the RFN and ion source, including beam current instability and RFN emission instability. A bright plasma halo around your target material that travels with the target when it changes position is a strong indication that electrons from the RFN cannot find a good ground surface.

Inside your RFN is a shaped metal Collector made of pure Nickel. Chosen for its conductivity and machining properties, the Nickel Collector serves as the electronic pathway for the ions in your RFN discharge chamber while the electrons are ejected through the orifice. However, Nickel and in particular hot Nickel react very quickly with oxygen and water vapor. This is why the RFN always operates on inert gases like Argon, even when the ion source is operating on Oxygen or other reactive gases. Further, when Nickel reacts, it does not develop a surface oxide layer like some metals. Rather, the reactant travels into the material. This allows the Collector to work longer, but also means that when it finally fails, it cannot be simply cleaned and reused. During a refurbishment the Collector should be replaced each and every time. Symptoms of a poorly-working

Collector include unstable RFN emission, inability to reach high emission levels, and over time an increase in required gas flow to the RFN due to increased erosion of the ceramic discharge chamber. All of these can cause complete process failure when the ion source in turn becomes unstable and goes out. A new Collector can provide as much as 3000 hours of performance before replacement.

At Plasma Process Group, we understand the importance of a functional RFN. We also understand how to disassemble, clean, and reassemble an RFN to reach the highest number of hours of performance between refurbishments. Send us your failing RFNs, and we’ll send them back cleaned, repaired, and ready-to-go, helping you keep system downtime as low as possible and results as consistent and reliable as your RFN!

Interested in more information on your RFN? We offer new RFNs but also take a look at our website here for more information about keeping your RFN in good condition as long as possible. Also, customers are welcome to obtain a free account to access training and instructional videos on RFN maintenance and refurbishment. As always, send us an e-mail or give us a call with any questions or to request a quote!

RFN Refurbish Service
RFN Refurbish Service

Plasma Process Group – Simple Ion Beam Solutions