In this episode, our guest is Professor Jaeyoun Kim from the Department of Electrical and Computer Engineering (ECpE) at Iowa State University (ISU). Here, we talk about his research on nanotechnology, microscale devices, optics and photonics for applications in nanomanufacturing and soft robotics. We also discuss about relevant coursework, research opportunities, facilities, and equipment available for students to build a solid background in this new, multidisciplinary area. This episode was conceptualized, recorded, edited, and produced by Santosh Pandey from the ECpE Department of Iowa State University. The transcript was prepared and edited by Yunsoo Park, Ankita and Richa Pathak from the ISU ECpE Department. The communications and digital hosting was handled by Kristin Clague from the ISU ECpE Department. The music was provided by SergeQuadrado from Pixabay (Track Title: Asian Sunrise).
Welcome to our ECpE podcast series where we talk about exciting activities within the department. I'm your host, Santosh Pandey. Our guest today is Professor Jaeyoun Kim from Electrical and Computer Engineering at Iowa State University. Dr. Kim, thank you so much for coming to our show. Today, we want to discuss your research on Nanotechnology, and Photonics, and more importantly, the scope of our students to develop the necessary skill sets in this field. To start with, could you tell our listeners about the buzzwords we hear today in this area, such as Soft Robotics, Triboelectricity, and Nano Manufacturing. I think that most important buzzword these days and the strongest trend these days is convergence. So, I talked about Triboelectricity, Soft Robotics, Nano Manufacturing. These are seemingly not related, but actually, they are very strongly related. So, the new findings in Triboelectricity is being utilized for Soft Robotics as a source of energy and also some sources of sensing. And then Nano manufacturing helps developing the ideas and all of these are intermixed and intermingled. And then we get some new things out of them. So, convergence is the biggest buzzword, and it's not just restricted to Soft Robotics, Triboelectricity, and Nano Manufacturing combination. It actually combines a lot more things, a lot more, a wider range of things into the same pot. So, you need skill sets from different fields of Engineering and Sciences? Science, Engineering, also Mathematics, and some other areas as well like Art. Okay. Could you describe some of your exciting research projects that you have done at Iowa State? Yeah, my most recent one is Nano Manufacturing based on Nanoscale Capillary Effect. Capillary Effect has been known to humans probably since time immemorial, but its nanoscale application has not been attempted much because there is no good way of measuring the Nanoscale Capillary Effect. Now we have them. Yeah, I mean, we can induce Nanoscale Capillary Effect and then freeze it at some point of time at a very precise point of time by shining laser on them. And then we can examine the surface using Atomic-scale Force Microscopy, AFM. And then I'm making some controllable nanoscale surfaces out of them. So, from my understanding, capillary effect was a macroscale phenomena. You are moving towards the other direction, like in nanoscale. Is there evidence in nature that, at nanoscale level, capillary effect has any value? Well, actually capillary effect is ubiquotous, it's everywhere. Whether you notice it or not, nanoscale Capillary Effect has been involved inside our body and even at molecular levels. We just didn't have the technology to measure them and then understand how it worked. So now we are approaching to obtain that ability with the advent of scanning probe microscope. And then I'm utilizing one of them in the form of Atomic Force Microscope. Is this project more geared towards understanding how natural systems work or is it towards creating an artificial man-made system? Actually, this project is two pronged. On one side, I try to find the basic dynamics of this Nanoscale Capillary Effect. And then on the other side, I try to utilize them to generate new technology, new technique for Nano Manufacturing. So, what are some of the core facilities and equipment that you have in your laboratory and within the department that helps your research? Well, my biggest weapon is actually the AFM, the Atomic Force Microscope, and we have a good one in our facility. And then I and my former graduate student actually developed it into KPFM. It is called Kelvin Probe Force Microscopy, which measures static electricity at nanoscale. So, is that equipment within the department and is it available to students to use? It belongs to the department. So, it's widely available to anyone who have interest in these measurements. Okay. So, students who are interested to use this equipment, they can come and talk to you to get the necessary training from your graduate student? Yes. And also they need to pay the fee. Few years back, you had done remarkable research on fabricating micro tentacles that mimic how insects and ants actually pick up objects. Yes. Could you briefly tell the audience what it was and where it was published and what was the impact? It came out in the news everywhere. Yeah, at the time, I was making a tube out of PDMS, PDMS is some kind of rubber. Okay. And it's a very elastic material. And then I tried to make a very, very thin tube, like a hundred micron in diameter, which is actually thinner than one strand of hair. Okay. And then, yeah, I punched the hole inside so that it can be hollow. And then when I pumped the air into it, it bent. And then I realized by accident, I realized that if I add a drop of PDMS around it, then it makes the shape a little bit uglier, and then that actually helps the bending of the tube under pressurization. And I played with the microtube and then I finally obtained some kind of device that mimics the tentacles of an octopus. It's made out of a very soft material. So actually I could grab an ant without killing it with that, a really small ant out of that. How long did it take from the design of the device to the accidental invention or discovery to the final publication? How long was that process? Well, I mean, from discovery to reporting takes only like a couple of months, I think. Okay. Yeah. So it's not a very long project? No. As I told you, when serendipity works, it takes a really short amount of time. It just takes time to arrive at the serendipity. Right. Who are the people involved in this project on micro tentacles? Actually, it was all done by only three people - myself and then my student Dr. Paek, now he's in University of Pennsylvania as a Postdoc and also Professor Cho in our Construction and Civil Engineering department. Myself and Dr. Paek did the experiment, and then the analysis was done by Professor Cho. So this project was funded by National Science Foundation. I assume. Actually it was our independent work. And then later, our research based on that tentacle was funded by National Science Foundation. Our work actually appeared in the main banner, main website of National Science Foundation. That was a very good, big prestige. Yes. And it also showed up on the department website and everyone, every student was aware of that. Yeah. That was a great achievement. So what do you think is the future of Soft Robotics and what are the applications that are currently being targeted in Soft Robotics? First of all, the future of Soft Robotics is very bright and it's being developed into something that is really applicable to our common everyday life. I can bring up two examples. First of all, yeah, we live in Iowa. So agriculture is almost everything. Right. And, yeah, I mean, these Soft Robots are great for harvesting fruits and other produces. Yeah. I mean, they are very fragile and then they are very soft. If you try to harvest them with a rigid robot. Yeah, It'll probably be nothing. But using soft robots, you can harvest them more safely, that's one thing. And second, of course, they'll be utilized more biomedical application. It can be utilized for sensing human body and also stimulating human body. Yeah. I mean, you don't want something rigid than human body to do the job. So those are the two main applications of Soft Robots in future. So, moving on to the next question, do you design, fabricate and test all your devices in your research lab within the department here itself? Yes. I can say that. My lab and also the Microelectronics Research Center, which belongs to Iowa State University - these are remarkably well equipped. Okay. So, how do you quantify the impact of your research or the novelty of new devices that you make in your lab? Is that based upon how high is the journal where you publish or how many people read your work? How do you quantify the innovation factor? Well, I think that citation record is the most important thing. It's our currency, common currency in science and technology these days. Actually, it's a common currency in academia as a whole. Okay. How do your students come up with new designs to fabricate these new structures and devices? Is that through reading the latest papers, discussing within your group, or trying several tricks in the lab? I would say that there are two major ways to arrive at new things. First of all, yes. I mean, as you just have mentioned, we could do the literature search and then do mix and match of existing ideas. I mean, we can get something new out of them. And second, yeah. Actually this one is more important, serendipity. So a lot of new things and especially new and useful things can be found by accident. Right. Of course, serendipity requires a lot of trials and errors. Right. So, how do you recruit new graduate and undergraduate what skill sets are you looking for in new students? Well, I follow the standard procedure. So I search the database of these graduate applicants and then I manually pick up some shortlisted applicants and then I interview them. Sometimes I get them, sometimes I couldn't, then I move on to the next one. That's a pretty standard. So, the best way to reach me is - sending email is okay. I read them every day. Do you have a website that is live and students can go there and read about your research? Yes. I think my website is not fancy or great by any standard, but I'm very keen on updating the publication list. I speak for myself through publications. Are there scholarships and funding available to new your research? Yeah. Currently I have a one student position opening. And how do undergraduate students approach you to join your research? Is it through the classes that you teach that you get interested students or they directly approach you by writing an email to you? Well, I don't think I have a preference on that. I mean, they can approach me, or they can just attend my course. But they don't have to actually, and my door is open all the time so they can just knock on the door or they can, or just walk in. Moving on to your teaching responsibilities. And you have taught a number of courses in Basic Electronics, Electromagnetics, Optics, and Bioengineering. Could you describe briefly some of these courses that you have taught and what is the value of these courses for students? First of all, I teach EE 311, which is a Electromagnetic Fields and Waves. This is a kind of rock bottom fundamental for all electrical engineers. So, I teach electricity and then magnetism and then electromagnetic waves, light, and then transmission lines. All these will be kind of bread and butter for future electrical engineers. I've been teaching this for like 15 consecutive years. Right. And I'm pretty good at it, that's for fall semester. In spring semesters, I move on to 438/538, which is OptoElectronics. It's about basic optic, which is my original specialty, main specialty. And I had the chance to teach this Introduction to BioMEMS and Nanotechnology course. And yeah, I mean, in that course, I survey recent progresses in BioMEMS and then Nanotechnology. So, coming back again to the question, what is the value of these courses in electromagnetics and optics for students or what students can benefit from taking these courses? First of all, they can learn the very basic theoretical background, especially in EE 311 which is mathematics intensive. You can learn a lot of mathematical tricks or skills with which you can analyze waves. And interesting thing is that the mathematics and then tricks that you learn from the 311 that electromagnetic field and waves can be applied to other wave phenomena, such as sound waves and then tidal waves. And also to signal processing and control systems. So, that is a very good plus to any electrical engineering student. Right. So it is a foundational course for someone who wants to build their career in this area. What are the other courses that you recommend? Yeah, of course I recommend your course on Semiconductor Devices and Physics to students. So, in the current industry, how do you think electromagnetics and semiconductors are intertwined or how is optics and semiconductors intertwined? Are there some latest developments going on in the field? Yeah, to me, they were never separated. They were never, they have never been separated. So, they have always been in just one, one big pot. You can't separate them and then you can't get one without the other. So, yeah silicon photonics or plasmonics and then biosensors and then soft microscale devices - all of this, they are all generating new waves in applications. And one, the biggest development recently is this foldable electronics. And I mean, you can purchase a foldable phone, smartphone from I mean, that's the result of the convergence that I mentioned earlier. Along with the coursework, it is also important to develop hands-on laboratory skills. What you recommend to student in this case, who want to go beyond the classroom learning, to get involved in learning some skills within research labs. To me, hand-on skills are everything. So, I really value the theoretical background and then mathematics. But in the end, what makes the difference is whether you can make it or not. So hand-on skills are really important and then it requires time to acquire. So, if you wanna acquire hands-on skills, then there's no other way, there's no royal road. You just need to knock on the door of faculty members and then get involved. And you need to act proactively. That's all I can say. Well, that is good advice for our students. What kind of career paths are pursued by students who graduate from your group? Where do they go for - do they go for further studies or they join industry? The majority of my graduates, they went to industry. So, I have one in Micron Technology, one in Rockwell Collins, another in ASML, so, and some more. And. Right. There is also one in academia. So he's a currently a postdoctoral researcher in University of Pennsylvania. And then he works on artificial lung and artificial everything, actually. All of these artificial organs are really important part of research these days and he's working on it. So. Right. Yeah. I, I mean, it's your choice. I just provide the very basic training and above all, I try to give them the way of thinking independently. Right. And using that, you can do whatever you want. So, one of your major job market for your graduating students is semiconductor industries, whether it is photolithography or new methods of lithotography that ASML, for example, does or semiconductor processing in leading companies like Micron and Samsung. Am I correct? Yes. That's true. And interesting thing is that their original research topics, especially for their dissertation, had nothing to do with their current jobs. What kind of skill sets are needed for students who want to interview to these top companies? Are these top companies looking for just the courses that students have taken or the list of publications? What else are these companies looking for? I would say the coursework's important. So they really have a look at the course list and then what they want, especially if these are big manufacturing companies, they treasure the ability to analyze stuffs. So mathematics skills, especially this experimental design and then statistical analysis, all of these skills are important. And then second of all, you need to have a firm background in your own field like semiconductor or optics. And as I told you, the mathematic or theoretical background that you obtain from one topic can be easily be transferred to another topic. But overall GPA of course important. And finally, if you have real hands-on skills, then it'll become a really big plus. So any final word of advice for students who want to emulate your academic success? Well, that's a very interesting question. I wanna say something like, stay hungry, stay foolish. In my case, I want the student, especially young students, to make a lot of trial and error. So you learn from mistakes. Yes. And you have to be smart and hardworking. Yeah. The better thing is actually to learn from someone else's mistake, but that opportunity is not always available in that case, you have to make your own. And at younger ages, it won't hurt much. So try a lot. That's what I tell the students. So, in the semiconductor industry, right now, there is cut-throat competition - whether it is TSMC, whether it's Micron or Intel. There is aggressive push for new technology to make devices smaller, to bring in new optics for lithography, for example. So there is a lot of value for patents, a lot of value for publications, but patents really are very important. So what is your thought on the competition that is there in the semiconductor market? It is good for our students because it is lucrative, but where do you see the semiconductor industry moving forward? I think they hit the wall these days. All the companies, they hit the wall. And then I heard that they are trying to reach three nanometer node. Yes. And what I heard continuously is that yeah. I mean, they can make it, but the yield is very low. So I think we will have to find a new way, a totally new architecture in transistor itself or a new architecture which will cover the deficiencies in the device level. Okay. I think that's all the questions that I had for today, and I hope our students actually listen to our discussion and learn a lot of things. Thank you again. Thank you.