Month: August 2016

From Intern to Analyst – Studying the Impact of ‘Non-Ideal’ Samples on Quant Results

Kylie Simpson and Robert Rosenthal, 2016 Summer Interns at EDAX

Being surrounded by equipment worth more than your average college student can even fathom is incredibly daunting. Your heart still skips a beat at every hiss or beep that the microscope produces. Not to mention the fear of ramming into the pole piece while inserting the EDS detector (we later learned there was a hard stop to prevent this but it never quite seemed to alleviate the fear). It’s hard to summarize all of the experiences from our internship at EDAX this summer. While it was only about two and a half months, the sheer amount knowledge we gained through hands on experience is unquantifiable. The five day EDS training course in itself contained enough information to be taught over an entire college semester.

Working with the Applications team gave us a real feel for what EDAX is all about. Not only did we get to work on a summer-long project, we also got to work with the marketing, engineering, and software teams on a regular basis. We also helped with support for the new APEX software. This work setting provided us with a plethora of new knowledge, not only of the physics and programming behind EDAX software but also of the inner workings of the company and the crucial role that teamwork plays in accomplishing tasks. Having access to an electron microscope as well as the specialized knowledge of the members of the Applications team enabled us to get the most out of our summer here at EDAX. After sitting in on a meeting with other members of the Applications team, we were exposed to some of the real-world problems faced by customers on a regular basis and decided to investigate this further with our summer project.

When collecting quantification results for EDS, the ZAF matrix corrections are based on the assumption that the sample is flat, homogeneous, and infinitely thick to the electron beam. Although these are the ideal collection requirements, many customers run into problems when their samples do not meet these assumptions. We spent our time here testing the impact of ‘non-ideal’ samples on quant results while also determining ways for customers to improve the accuracy of quant results with these samples. We tested samples with rough topography by scratching up and polishing a stainless steel and a pyrite sample (Figure 1). By collecting a counts per second map for the steel (Figure 2), we were able to visualize the impact of rough samples and confirm the need for sample prep.

Figure 1. Pyrite particles and polished pyrite Figure 2. CPS maps of stainless steel surfaces

We also tested inhomogeneous samples, including a Lead-Tin solder sample and a stainless steel sample (pictured below). By collecting spectra of these samples at different magnifications, we observed the correlation between lower magnification and a higher accuracy of quant results.

Figure 3: Lead-Tin solder and stainless steel samples

Figure 3: Lead-Tin solder and stainless steel samples

Finally, we tested the impact of thin samples on quant results using an aluminum coated piece of silicon. This sample was very hard to obtain, being that we had to coat the silicon five separate times, but it yielded very interesting results (see graph (left) in Figure 4 below). Our results illustrated the influence and importance of collecting spectra while also allowing us to back-calculate the thickness of each aluminum layer (pictured in Figure 4 (right) below).

Figure 4.

Figure 4.

Overall, we thoroughly enjoyed our summer at EDAX and will take away not only knowledge of EDS, EBSD, SEMs, computer programming, and teamwork, but also valuable problem solving skills applicable to classes, professions, and other real-world scenarios that we will encounter in the future.

Meet the Interns

Kylie Simpson: Kylie is currently a student at the Thayer School of Engineering at Dartmouth. She is participating in a duel-degree program with Colby College and Dartmouth College and is studying mechanical engineering and physics.

Robert Rosenthal: Robbie is currently a student at the University of Colorado at Boulder. He in going into his junior year studying Mechanical Engineering.

Training classes and You

Shawn Wallace, Applications Engineer, EDAX

Over the last month or so, I have spent quite a bit of time training people on our systems. Between a workshop, the Lehigh Microscopy school, two webinars, and two in-house training courses, I have interacted with all levels of users. This had me thinking back to my experiences, years ago on the other side of the desk in the EDAX classroom and what I learned from the courses. With that in mind, I began thinking about what our customers/students can do to get the best out of our training sessions.
Lunch and Learn M&M 2016
The biggest thing they can do is to spend time familiarizing themselves with the general operation of their complete system: their SEM, our systems, and most importantly, with their samples.  Sit down, fiddle with things and just learn how different settings interact; Amp time and Deadtime for EDS, Camera settings for EBSD (see my ‘Camera Optimization’ webinar). The main thing this does is makes you start thinking about what these settings are doing and how they work with your samples. While you do this, you will start to formulate questions in your mind. For some of these questions you will be able to come to an answer. Some will be directly answered during the course. Others will click while you listen and make connections to your work and I will see that ‘Aha!’ moment on your face as you figure out, why that little trick worked or possibly failed miserably.  By spending the time to figure out things on your own, you are getting in the right mindset to come to our courses and ask questions.

This leads to the second biggest thing you can do: Ask me questions! That is why engaging with your system is so important. You are setting yourself up to ask pertinent questions about your samples and your systems. You are finding your natural work flow, but our job is to help you to optimize it, to help you to understand what you are doing, and most importantly help you to understand why you should do it that way. This is why running your system with your samples is a very important thing to do before you come to our courses.

Another reason for asking questions is that you need to be an active learner and engage with your instructor (aka me). Ever sat in a college class and had the teacher just talk and talk and talk for hours on a subject as you sip your coffee to try to keep yourself from dozing off? Ever taught a class and looked at the faces of people sipping their coffee as their heads do that little nod as they fail to stay awake? It’s not fun for either person. I always start my training courses by saying that I want questions. I want you to be engaged and thinking during the entirety of my courses. I want it to not be a lecture, but a conversation. I want that instant feedback to help me understand what concepts you are struggling with and what topics are clicking, so that I can dive deeper into subjects that I need to.
Classroom-small
That’s it. That is all you need to do to come to our courses and get the most out of them. Be prepared and be engaged. You will absorb the information we are giving you and you will be able to take it home and put it to use to get better and faster results, while understanding what the system is doing at a much deeper level.

With all that said, there is one more important step. You should never stop learning. Luckily for you, the applications team here at EDAX is always creating new resources for our customers to use to learn with. Sometimes it is quick blog post about some neat new feature we have implemented, at other times it’s a webinar covering the most difficult aspects of microanalysis.

I hope to see you soon on the other side of a desk. Happy Learning in the meantime!

Click here for more information about upcoming EDAX training sessions.