23 October | Rasmus Pedersen

Interview with Rasmus Pedersen, Senior Field Process Engineer

This Service Blog post follows an online interview with Rasmus Pedersen (RP), one of Oxford Instruments Plasma Technology’s senior field process engineers. Rasmus works with many of our customers in Europe. Read the post to learn more about our field process engineering expertise.

In the interview, conducted in May 2023, Rasmus outlines how his experience and knowledge helps customers meet their process needs and explains how we promptly and effectively solve challenges that arise in the field.

What’s your background and how did you enter the semiconductor industry?

(RP) I got interested in semiconductor processing early on during my university education in applied physics. I did a PhD in nanoimprint lithography and afterwards some years as a postdoctoral researcher working on a wide variety of micro and nanofabrication techniques. After deciding to leave the academic sector Oxford Instruments had a good opportunity available and I jumped at the chance.

Can you explain in simple terms the role that field process engineering plays within the semiconductor industry?

(RP) Process Engineering clearly plays a crucial role in the semiconductor industry, not least in enabling the production of progressively-smaller and increasingly-complex semiconductor devices and in improving process stability, repeatability, and yield. Process engineers must understand elements of chemistry, materials science, electronics, physics, mathematics and more, to develop and optimise processes on advanced equipment, which are critical in the intensely competitive semiconductor industry. It’s also worth mentioning that there are key differences between field process engineering and laboratory-based process engineering. One obvious difference is that in the field, there’s tremendous pressure to solve challenges very quickly, because there are often significant commercial imperatives to maintain high production up-time.

Which customers do you work with and what do they produce?

(RP) I work for many different customers throughout Europe, including those operating in high-volume production and others involved in research and development. Often, I’m not privy to the details of the devices that our customers are involved in producing because this is commercially sensitive information. Whilst I work across our etch and deposition systems, most of my work, around 90 per cent in fact, involves our etching systems.

So, what are the main aspects of your job as a field process engineer?

(RP) I’d say there are three main aspects to working as a field process engineer at Oxford Instruments Plasma Technology:

1. Firstly, there’s the Process Acceptance work. This essentially involves demonstrating or proving that our systems do what we say they do
2. I also train our customers’ system operators how to operate our system/s safely and effectively
3. And then, the final aspect is that I’m troubleshooting. This work responds to customers if they face processing challenges in the field and usually involves collaborating with customers and colleagues. Often, challenges arise when a customer introduces changes, maybe a change to their usual process, perhaps they’re using a new size of wafer, a new gas, or there’s been some kind of hardware component failure

Obviously, all aspects of your job are important but I guess Process Acceptance work has particular importance. After all, customers buy our systems to perform very specific processes, so it’s crucial that we can quickly and effectively show them that our system performs as we say it will, right?

(RP) Yes, absolutely, of course, you’re right. All aspects of my job are important but Process Acceptance is crucial because customers need to know that our systems run their processes in the ways we say they perform! It’s also important to finalise process acceptance work as quickly as possible, especially for our high-volume production customers who face potentially significant financial downsides or lost opportunities in the event of delays. Fortunately, the high-quality design and build of our systems means the vast majority of my Process Acceptance jobs are relatively straightforward, in fact, it’s common for me to be in and out of a customer site within a week or two of process testing and system training.

It's also the case that the specifics of a customer’s wafers and devices can demand modifications to a “standard process” to achieve the optimal process performance. Sometimes I need to make bespoke adjustments or adaptations so that a process works in accordance with a customer’s specific needs, all customers are different. And, of course, plasma etching can be sensitive to subtle environmental changes, so my years of experience in solving process challenges means I can work effectively and quickly to satisfy our customers’ needs. Overcoming challenges promptly is important because customers have a critical need to maintain their production lines. This is where the knowledge and experience I’ve developed over many years, backed-up by the collective experience of many great colleagues throughout the Oxford Instruments group, makes a real difference.

What happens if a customer decides to introduce changes to the processes they’re running on our systems, does this process present challenges in the field?

(RP) As I said, plasma etching is sensitive to small environmental changes. Changes to the gases being used is a good example. So, if a customer starts using a new gas that has even tiny amounts of impurities, then this change can be sufficient to disrupt an otherwise stable process. Also, customers introducing new wafers often require additional support to adapt their process for the substrate changes. Obviously, changing wafers and changing processes is not so common amongst high-volume production customers but it’s certainly a common feature within the research and development field, a sector that’s largely involved in experimenting with different processes and methods, so change is simply part of what they do. And, of course, research institutions frequently recruit new academics, who usually have their own projects to pursue, often involving new process requirements and new challenges.

And how does Oxford Instruments help customers’ that want to pursue new or changed processes?

(RP) We offer our customers several options on process solutions. With our range and depth of process experience and expertise, we’ve developed one of the strongest libraries of processes and capabilities anywhere in the world. So, our customers can get direct access to our team of applications experts, as well as our extensive recipe library, which has more than 8,000 recipes across multiple platforms. Sharing the decades of Oxford Instruments Plasma Technology’s process knowledge is a big part of how we help customers deliver the advanced and stable solutions they need to maximise device performance. We can really make a difference here.

So, what about the third aspect of your work, troubleshooting? What kind of challenges does this present and can you share an example of how we solve processing problems in the field?

(RP) Troubleshooting’s an inevitable part of being a field process engineer, problems will inevitably arise in the field, this is simply the nature of the work and the semiconductor industry more generally. Process challenges in the field are sometimes traced back to hardware issues, the failure of component parts, for example. This is not surprising, of course, because moving engineered parts are subjected to intense wear and tear, so it’s inevitable they’ll need replacing at some point in time. Another example might be a malfunctioning mass flow controller causing plasma instabilities in a very high-performance etching process that can result in unreliable etch performance. To troubleshoot this kind of issue requires experience and knowledge. The key is to quickly and correctly identify the source of the problem, so that we can ensure a successful hardware intervention, whilst minimising the impact of the intervention on other parts of the fab.