The Opportunities for Plasma Processing
Pete Starkey interviewed Andre Bodegom, managing director of Netherlands-based Adeon Technologies B.V., about their long relationship with Nordson MARCH, typical applications for plasma equipment, and what the most challenging materials are from the point of view of plasma processing in the PCB industry.
Pete Starkey: Andre, thank you for joining us. Why don't you start by introducing the nature of the Nordson MARCH plasma equipment and it's applications in the PCB industry?
Andre Bodegom: We have represented Nordson MARCH as distributors since 2001. Back then, we selected it due to the high uniformity that their plasma systems were providing. As you know, in the batch process in PCB manufacturing, it is extremely important that the uniformity for the first panel is as good as for the last panel in the same batch, but also throughout different batches. It needs to be capable of working with basically all the materials that people would like to treat with plasma.
It’s been a long relationship, and we’ve been very happy to stay because of the Nordson MARCH plasma support, and also the technology developments that they provide.
Starkey: What are the typical applications this is used for in PCB fabrication, including what operations and at what stage of the manufacturing process?
Bodegom: There are really three to four different types of applications. By far the most important is still desmear and etch-back—the hole-cleaning process. Also, plasma is widely used for material activation and surface preparation. Due to a really wide variety of all sorts of materials that are used in the market today, this is the reason why we believe these systems are one of the better ones out there, because they are capable of treating all sorts of different materials.
Starkey: In your opinion, what are the most challenging materials from the point of view of plasma processing?
Bodegom: It's a combination of materials, as well as chemistry. It is really not a machine you're selling, it's a process that we're implementing for customers. We have a lot of different experiences with various types of chemistry, used after or even before plasma treatment, and reaching out with Nordson MARCH h behind us to those chemistry suppliers provides a better machine for the customers at the end of the day. There are more challenging materials like LCPs that are coming in, and a variety of flexible materials. And it's the combination of materials and chemistry that people are using. Different brands of chemistry tend to react differently with different types of materials before and after plasma treatment. Therefore, with the Nordson MARCH organization behind us, we’re capable of reaching out to chemistry suppliers and have their cooperation to work towards better results for the customers.
Starkey: On the one hand, the plasma is doing a job that you can't do with chemistry, but on the other hand, the effect of the plasma has got to be compatible with the subsequent chemistry that you're using, so you need to work in close collaboration with the chemistry suppliers and with the PCB fabricators.
Bodegom: I wouldn't go as far as saying that the processes are not possible with certain chemistry. It's just that plasma provides a number of advantages in various applications and at various stages of the process due to the fact that it has no waste. It's very compact, and there’s no real estate for a machine to set up; and of course, the exhaust of the system is clean. It provides a lot of advantages for certain types of applications, predominantly in Europe, with prototype manufacturing where plasma as a one-stop shop actually can provide a lot more advantages.
Starkey: A typical user of plasma in the European PCB fabrication industry would be someone engaged in military-type work, aerospace work, and medical work?
Bodegom: Yes, high layer count, and a high mix of different materials and in low volumes, so being able to switch from process to process very quickly by just actually selecting another set of parameters for the machine to act differently on a particular batch of boards. And that can be varied between batches.
Starkey: If we look at recent developments, enhancements, and new features of the equipment, which way are you developing and which way are you being driven by the market requirements?
Bodegom: Nordson MARCH started to introduce what they call ProVIA and MaxVIA technology roughly four years ago. It’s a little bit technical, so I might not be the best one to explain that, but in their older plasma systems, we used to have a cross pumping gas-in gas-out system. Thus, we would have the gas in at one end, and vacuum out at the other end, and then we would cross-pump that every minute; but it would really come in from the side, and go out from the side.
We also had barred electrodes. One of the advantages of those barred electrodes was that they were hollow and water cooled. What Nordson MARCH has achieved is they’ve moved from these barred electrodes to closed electrodes, and effectively therefore achieved an even higher uniformity.
One could almost say that it's easier to generate the plasma in these cells in between the closed electrodes, but also temperature-wise it's a more enclosed area per cell. The preparation process goes faster, and the process temperature is achieved faster.
Because every cell really has its own smaller area of plasma effectivity, it creates the higher uniformity. In addition to that the gas inlet system has changed and obviously with closed electrodes we’re now coming in from the top to the bottom, so every cell gets its gases very efficiently and very fast.
Starkey: Thanks for the explanation. Andre, thanks very much indeed for your time.
Bodegom: Thank you, Pete.