The journey of a physicist from the realm of fundamental research to an R&D focused & market driven role in the Hi-Tech industry is not just about translational skills but also about assimilating and adapting to constantly changing technology & business requirements !

Sujatha Sampath, our next pathbreaker, Sr. R&D Technologist at Texas Instruments, works on Analog and Embedded next-generation microchip technologies.

Sujatha talks to Shyam Krishnamurthy from The Interview Portal about her specialization in Condensed Matter Physics and her work on multi-disciplinary problems in emerging materials with applications in technological glasses, semi‐conductors, energy‐storage and biomimetics.

For students, as long as you have a strong foundation in the fundamentals and core concepts of your choice, you shouldn’t have a problem adapting to the rapidly changing technology landscape !

Sujatha, tell us what were your early years like?

My family is from Tamil Nādu. I am the older of two girls in my home.  My father is an engineer (retired), and my mother a homemaker. My sister and I grew up in both southern and northern parts of India, due to my father’s job with the central government of India, which was transferrable. 

I studied from elementary to high school in Kendriya Vidyalaya, also known as central school, a system of public schools affiliated with the CBSE board. I was curious from a young age, I did well in all subjects, but was naturally inclined to Math and Science. In high school, I got more interested in Physics and Math. I took part in many of the extra-curricular activities in school – I was part of the school music group (I’ve been learning Indian classical music since I was about 6-7 years old), participated in intra and inter school competitions – compositional/essay writing, debates and art. I was a girls scout and captain of one of the house teams in school. I got interested in art from very early on, drawing, painting, a hobby I still seriously pursue. 

I cherish my years in Kendriya Vidyalaya. I am thankful to my teachers and the school system in general, which fostered conceptual learning and from my experience, I got a well-rounded student life. 

What did you do for graduation/post graduation?

When I was graduating from high school, it was customary and expected that if a student was among the top rankers in the science /math group, she/he would go for either engineering or medicine as a career path. I applied to engineering schools and got admission in good engineering programs, but then, studying physics resonated with me more, and I chose to pursue an undergraduate in Physics. I decided to follow my strong interest in basic sciences, and went for a Master’s degree in Physics.
After my master’s, I had to decide on whether I wanted to go for a PhD, continue in research, or pursue other professional options. It was a no-brainer for me that I wanted to continue in Physics, and pursue a research career. My parents supported my choice of going for a PhD, for which I am very grateful.

Another choice I had to make was whether to go abroad or pursue a PhD program in India. In my case, it made sense to stay in India, considering a few other family factors at that time. One of my professors asked me to consider a few new premier research institutions that were coming up in India at that time, in addition to the older established research institutions. I chose to go for my PhD in Condensed Matter Physics, at the UGC-DAE Consortium for Scientific Research (UGC-DAE CSR). I was among the first batch of students to graduate, which again, in retrospect, was a valuable experience, because I learned to build a lab from scratch, as the first student of my advisor in a relatively new research institution.

UGC-DAE CSR is a national scientific user center which provides its advanced facilities to research groups from around the country. Since the institution was relatively new at that time, and hiring for laboratory staff was still ongoing, the first batch of students put on additional hats – in addition to their own PhD work, to help with design and execution of experimental and data plans for external users for their projects. This was not a common experience for a graduate student, and though it felt challenging to navigate through all these demands, I got some experience that I was able to leverage later in my career.     

After my PhD, I wanted to continue in research and applied for post-doctoral research positions.  I got a postdoctoral fellowship at Argonne National Laboratory (ANL) in Chicago USA, one of the few places in the world at that time to have a 3rd generation synchrotron ring and a neutron source in the same campus. In ANL, was the start of my career as a professional physicist.  

What were some of the influences that led you to such an offbeat, unconventional and rare career of a Physicist?

I’ve been asked this question in recent years –  ‘when did I know I wanted to be a physicist’ ? In my case, there wasn’t one ‘aha’ moment or one particular event that steered me in this path. I was deeply interested in Physics and even when I was in high school, tried to get my hands on books outside of my school curriculum to read more on physics topics. Understanding the fundamentals was very important to me and I worked hard at it. In college, Feynman Lectures were my all-time favorite set of Physics reference books. I’d be glued within those pages. I found the concepts were well explained, very eye-opening of sorts, and I’ve a copy of Feynman lectures which I refer to sometimes even to this date. 

At every point in my education when I had to make my next choice, it was a natural progression to choose physics and that eventually led to me becoming a professional physicist. 

How did you plan the steps to get into the career you wanted? Or how did you make a transition to a new career? Tell us about your career path

As I mentioned, I chose to pursue my PhD in Condensed matter physics (CMP), a field that deals with collective interactions and states of matter that form when a large number of constituents – atoms, molecules, electrons – interact, leading to exotic material properties. Understanding structure at scales from atomic to nanoscale in a solid or liquid system, and its direct impact on material properties is the focus of condensed matter research. Phenomena of interest in CMP happens in the realm of quantum physics and quantum statistics. Concepts integral to CMP are applicable to a wide range of disciplines like material science and engineering, bio-physics, chemical physics to name a few. I studied the fundamental physics of disordered systems for my PhD, in particular, amorphous and glass structure and dynamics. 

After my post-doctoral position, I continued as a scientist in fundamental research, working on problems in nanoscience and nanotechnology at synchrotron and neutron beamlines in national laboratories. 
My career path is anything but linear. After many years of working in fundamental research, I moved to a R&D position in the semiconductor chip industry, focusing on advanced and emerging microchip technologies. Moving from a domain that was largely research based, to an industry where development in addition to research, is a big part of R&D, I found that at the core, it involves problem solving in both domains. There were quite a few skills that I could translate from my role as a scientist in a national laboratory to my current role in the semiconductor industry, while assimilating new skills as relevant. 

How did you get your first break?

My first break was my post-doctoral fellowship position at Argonne National Laboratory right around my PhD dissertation. This was a phenomenal place for a young “fresh out of graduate school” researcher to be in. I got an opportunity to work with and collaborate with senior scientists, some of who are pioneers in the field, an experience I would always treasure. 

What were some of the challenges you faced? How did you address them?

Challenge 1: 

A PhD is unlike any other educational pursuit. You go into uncharted waters, to explore, define the problem you want to find solutions to, for most part persist, learn, re-learn from approaches that didn’t work before, until you unravel the solution. I joined a new Lab as the first student of my advisor, as did some of my graduate school friends, at UGC-DAE CSR. This was a new research institution and I didn’t have the luxury of learning from senior students/postdocs, or role models, potential options available in older research laboratories.  We started with an empty lab space, and built the laboratory and charted the course of the research program from ground up. 

The fact that this seemed a challenge is more in retrospect, after I graduated and moved further in my research career. At that time, I took this status-quo as a baseline from which to start, to work on my PhD, start with instrumentation for my experiments – design and build experimental probes, data acquisition systems, learn to work with cryogens and vacuum systems. To accomplish these different parts to building a experimental lab, I had to work with our procurement department to order the required electronic measurement systems, get probes fabricated, and at one point even learnt to operate a lathe in our machine shop so I could get brass flanges for a probe machined quickly rather than waiting in queue of jobs in pipeline. In addition, as I mentioned earlier, the first batch of students also supported user related work since this was a national user facility. 

Takeaway is that I was deeply interested in how nature worked at the tiniest of scales of the universe, and I persisted. The moment you realize you’ve figured out why something works the way it does, and you are probably the first or one of the few people in the world to have cracked that piece of code of how nature works, its’ purely exhilarating.  Looking back, experience of 6 years during my PhD was like working in a start-up, wearing many hats depending on what needed to be done, learning technical and soft skills to get to the goal post of finding the solution to the PhD problem and graduating successfully, while also help pave the roadmap for the laboratory and the institution’s continued success.

At times when things were weighing down morale, as is the case with many PhD journeys, camaraderie with my fellow graduate student-friends kept me going. I am grateful to my family’s confidence and support  in my pursuits, and to the few good Samaritans in the community for friendship and giving me a home away from home ambience. I also kept my drawing/painting efforts, my interest in classical music and reading alive (which was a challenge in itself after typical 14-hour days for 6 years), all of which were very helpful as I was wading through the uncharted waters, in my PhD journey. 

Challenge 2: 

After my PhD, I was offered a post-doctoral fellowship at Argonne National Laboratory  in a joint position with a university research group.  I was in a new country, a new culture, with not too much time to get acquainted and settled, and had to hit the ground running. Neutron and Synchrotron beamlines are operational 24/7 and my role was to work on my research projects while also training and assisting external researchers/users execute their projects on the X-ray and Neutron beamlines.

Working in beamlines, required quick thinking on the feet, changing experimental plans on the fly, depending on multiple factors. It requires a lot of planning ahead, because experimental beamtimes were finite, due to heavy demand by researchers from all over the world. This meant having back up plans, bracing for failures, and unforeseen technical problems that could ruin months of work in preparation to run experiments at these synchrotron and neutron facilities. And despite all the planning, there could be times when experiments couldn’t run as per schedule.  These experiences can certainly test one’s resilience, particularly as a junior researcher. I loved the research work, which kept me going as I was trying to establish my career and my life in a new country.  

Challenge 3

I made a career move to a R&D role in the high-tech semiconductor industry a few years back. I joined IMFLASH technologies, a joint venture between two iconic semiconductor companies, Intel and Micron Technology. They were pioneering a revolutionary non-volatile memory technology, the 3D Xpoint.
Due to business and market driven decisions, the Fab went through major change of hands, in a span of a few years. Uncertainty loomed high at times, and with each company change, technology focus and product portfolio were very different. These kinds of business turnovers require quick learning, for not only the technical aspects of a new product space, but also working through different operating styles and cultures to be able to contribute effectively to the company’s goals. No matter when it happens in one’s career, these kinds of uncertainties affect everybody, in this case amplified by the timing, as the world was going through the covid19 pandemic. Thankfully, through continuous learning, resilience & adaptability built through years in a research career, I was able to persist and be effective, through this roller-coaster ride.      

Where do you work now? 

I work at Texas Instruments, as a senior R&D technologist. 

What problems do you solve?

I design, develop and optimize semiconductor process modalities for advanced CMOS in embedded and analog microchip technologies.

What skills are needed in your role? How did you acquire the skills?

My role involves both research and development. For both these facets, a depth of knowledge in fundamental semiconductor and device physics, as well as understanding different process modalities used to develop a micro-chip are paramount. In addition, there are many experimental, analytical and data skills required. 

Innovation to find new solutions, that not only require higher technical performance, but also to scale-up technologies to high yield and volume, while being cost-effective, is a space I am constantly in. 

I was able to translate core research skills from my experience as a scientist in a national laboratory to meet requirements in my current role. I learnt a few new skills, particularly in product development, fab operations, business and market specific knowledge by just diving in, learning along, gauging priorities and being open to learn whatever it takes to solve the problem at hand. 

What’s a typical day like?

For starters, no two days are alike. A typical day can be a combination of a few items from a list of – technical and business meetings, working on experiments, data analysis, path-finding projects in emerging areas, solving process/equipment problems with alternate pathways. 

What is it you love about this job? 

I like the fact that I am able to use my experience, expertise and domain knowledge as a physicist to develop semiconductor microchips, a technology so ubiquitous that it has an impact in almost every aspect of our lives, from our computers, smartphones, personal electronics, to healthcare, transportation, communication, banking, data centers and applications in AI.  

How does your work benefit society?

As a research physicist, I have worked on multi-disciplinary problems in emerging materials with applications in technological glasses, semi‐conductors, energy‐storage and biomimetics. In my current role in the semiconductor chip industry, I work on developing next generation microchips that will enable higher performance and cost-effective solutions to a wide range of applications as I mentioned above.

I frequently get invited to talk to students and educators about my work, and my career journey in STEM. Sharing what makes me persist in the scientific field, and the ability to impact society not only through my research, but also by influencing younger students to pursue STEM as a viable career, I hope, is beneficial. I write articles in my blog to share my views on STEM and Arts, two domains – I am passionate about.  

Tell us an example of a specific memorable work you did that is very close to you!

While every research problem I worked on is special to me, a couple of examples stand out. 

While at ANL, I was the lead physicist in a multi-disciplinary project in biomimetics to study natural spider-silks, a bio-material with amazing material properties. Biomimetics is an interdisciplinary field in which principles from engineering, chemistry and biology are applied to the synthesis of materials, synthetic systems or machines that have functions that mimic biological processes.

The objective was to investigate the hierarchical structure and properties of the natural spider-silks, and apply the knowledge to engineer synthetic spider-silks and ‘designer’ bio-polymers for various applications, by mimicking and learning from nature. This project involved collaborative effort and expertise from multiple scientific domains to understand and decipher how nature made these bio-materials. When I first started on this project, I didn’t know much about the biology of spiders nor protein-chemistry. Even though I was directly focused on the nanoscale structure and properties of the silk that spiders spin, I got to learn quite a bit in the field of biomimetics. I was invited to give a TEDx talk on this research, and just a day before my talk, one of my friend’s 10-year-old son asked her, “why is a physicist talking about spider-silks”? And that precisely was the point this project is extra special to me – as a condensed matter physicist, I was helping solve a problem in biomimetics with far-reaching impact, with physics-based methods.      

Another example is in my current R&D role in the semiconductor chip industry over the last few years, working on current and next generation chip technologies. Semiconductor chips are ubiquitous in our daily lives. They are almost in everything we use, personal electronics, data centers, transportation, healthcare among other uses. Developing a scalable, high performance semiconductor chip that is cost effective is a challenge, more so as the node sizes are shrinking. It takes a combination of fundamental research and pushing boundaries of performance via advancements in process technologies, to build a product with high quality and reliability.  It requires a confluence of expertise in science and engineering disciplines that have to work in synchrony, to build a semiconductor chip, designing and building it atom by atom.  

When I moved to the semiconductor industry, I started working on the 3D Xpoint technology, a revolutionary non-volatile memory technology using phase change memory (PCM).  I worked on the physics of PCM materials in my PhD.  To develop a product using the same class of materials I had worked on in my PhD, was very meaningful to me. To work on both facets of a class of materials from basic physics to technology development is a unique opportunity for a scientist.  

Your advice to students based on your experience?

My advice to students is to get a strong foundation in the fundamentals and core concepts in your choice of field. Persistence, continuous learning and adaptability are key to navigating the rapidly changing requirements of skills needed in the current professional world.  Above all, when possible, opt to apply your skills to solve problems that have a global impact.                       

Future Plans?

I would like to continue doing what I’ve enjoyed the most, and the reason that got me to where I am today – crack the code of how nature works and leverage that knowledge to build technology and applications that benefit society at large.