Aarón Garcia-Luque, Internship Award Winner 2021
Q: Why did you decide to apply? What opportunities were you looking for?
In my opinion, “engineering” means trying to improve the efficiency and performance of current technological advances. In that way, I firmly believe that “globalization” is not only a social concept, but also a scientific one and, definitely, at a research level there are no borders or national limitations. The world is changing and, to move forward, it is essential to apply for exchanges, meet new researchers, connect with other cultures and be ready to understand and share knowledge, methodologies and skills. For these reasons, I have always wanted to learn abroad and to have the experience of being aware about how technology is enhancing our society day by day from a point of view far away from my home.
This motivation led me to apply for my Master’s Thesis in another country but COVID-19 screwed up this possibility and this EuMA Internship Award was the opportunity I was looking for a year later.
Q: How did you choose your host?
My home supervisor told me wonders about prof. Ingmar Kallfass when she met him at the EuMW Madrid 2018. In addition to this, the Institute of Robust Power Semiconductor Systems (ILH, Stuttgart) has years of well-known experience in semiconductors and nonlinear active devices modeling for microwave and millimeter wave devices, which is the main topic of my current PhD work. A couple of video calls were enough to realize that this choice was a complete success, better impossible.
Part of the Institute of Robust Power Semiconductor Systems (ILH) staff
Q: What was your experience like during your internship at the hosting
organization?
Absolutely perfect! On the one hand, the city of Stuttgart is beautiful. I really liked the whole natural landscapes, mountains, lakes and the perfect balance between classic architecture in contrast to a very high industrial development clearly appreciable, for example, in a powerful automotive sector. On the other hand, concerning the professional aspect, let me tell you that from the first week I felt myself in my own home. I have no words to express my true gratitude to all the staff, indeed, it was always easy to find someone glad to support me when I needed it and we held meetings very frequently in order to discuss our progress and in order to allow everyone’s collaboration with everyone. From the technical point of view, I was really privileged because not only working on the modeling of novel AlGaN/GaN transistors but being able to perform measurement and calibration tasks inside professional laboratories and industrial cleanrooms.
Q: What projects did you work on during your internship?
My activities in Stuttgart were very varied, mainly three milestones must be highlighted:
Firstly I was able to measure, characterize and model GaAs and novel AlGaN/GaN High Electron Mobility Transistors (HEMT) from multi-bias S-parameters and typical DC-outputs.
These tasks included calibration tasks, dealing with professional RF setups and data processing, simulation and optimization of the different extracted models in CAD tools.
All these works were possible thanks to a collaboration with the Institut für Mikroelektronik Stuttgart (IMS Chips) to whom I am very grateful not only for the manufacturing and processing of those wafers but for the training they provided me in the novel state-of-the-art GaN-based semiconductors and charge trapping issues.
As a part of the many projects in which the ILH is involved, I was able to work on Time-Domain Reflectometry (TDR) for failure analysis and, last but not least, I would also like to point out that I was allowed to support several Master’s and Bachelor's Theses which were carried out by students at the ILH. I am very grateful and happy with everything I learned there.
ILH lab entrance and IMS Chips cleanroom facilities, together with on-wafer setups
Q: What were the outcomes of your projects?
As a result of the developed work in Germany, up to three publications in international congresses have been accepted in recent months. In particular, a paper about the modeling strategy and optimization was published at the International Workshop on Integrated Nonlinear Microwave and Millimetre-Wave Circuits (INMMIC Cardiff 2022), a novel paper about the Development and RF-Performance of AlGaN/GaN and InAlN/GaN HEMTs on Large-Diameter High-Resistivity Silicon Substrates was accepted at the European Microwave Integrated Circuits Conference (EuMIC) at the EuMW Milan 2022 and, also, a work about novel processed on-going devices at GaN Marathon (Venice 2022).
Q: What was your favorite part of the internship?
I must say that’s probably the easier answer, people. What made this experience absolutely priceless was the great family I found there. Some great professionals, now friends, who made every day there unforgettable. I really enjoyed every team meeting and being able to share experiences, learn together and get all involved in everyone’s work.
Measurement’s time at IMS Chips cleanroom
Q: How did you find the supervision?
There is not enough space in this interview to thank the whole list of people to whom I am grateful for this opportunity. I was very lucky because every time I needed help, someone was there to offer it. However, there are three of them that I would like to highlight. Many thanks to prof. Ingmar Kallfass for opening his home to me, for treating me from the very first week as one more of the team and for trusting me every day. His support was incalculable at every moment and he has made me grow a lot as an engineer and as a person. Secondly, I only have good words for Dr. Mohammed Alomari due to all his teachings about novel GaN devices and, last but not least, I also would like to thank my local supervisor, prof. Teresa M. Martín-Guerrero for encouraging me to apply for this internship and, also, for taking care from me from the distance.
Q: How will the internship affect your further career?
In those four months I have been able to learn a lot. At the formative level, I have been supported by very well-known professionals and I could deal with state-of-the-art novel RF devices. As personal milestones, I have not only improved languages but also met many valuable people and I have discovered the meaning of effort. Apart from the academic records, I think I am a more mature and reasonable person and this is why this experience is priceless. Undoubtedly, I recommend the ILH to anyone who wants to learn in the microwaves and millimeter-waves.
On-wafer setup and HEMTs mask ready for processing, measurement and modeling
Q: What are your plans after the internship?
I am currently in my second year of PhD. My short-term idea is to finish it and, once completed, we will see. I am not sure where I will be, I love my city but I have discovered that there are many places to call “home”. I have learned that with effort, all barriers and challenges are surmountable. The only thing that is clear to me is that I like my job and I would love to be able to go on learning in the future.
Q: Is there any advice you would give to someone looking for an internship in microwaves?
I only have three words for those who might be interested: passion, effort and courage.
This award has changed my life and I believe that getting out of your comfort zone, seeing the world and learning from others is the best way to grow up not just as a professional but also as a person. I would like to encourage all to live this experience and I am very grateful to EuMA for making it possible in my case.
