 Είμαστε εδώ στο Nanotexology, για την τεσσαλανίκη. Ποιος είστε εδώ. Είμαι Κυριακος Κυμβόμπλος, προφέσω της Μεκανικής Αντζινέρης, στον κερδιστικό της Καλυφόνιας. Πάμε εδώ, εδώ και εδώ. Μπορείτε να του κομμάστε πίσω. Καλυφόνια, Μπερκλή, τι κάνετε εκεί. Είμαι πρόσφερο της Μεκανικής Ανγυνένειας, but the focus of my work also is related to the theme of this conference, which is nanotechnology and nanosciences. That is the new technologies and the new fields of science that are concerned with the behavior of material and devices at the nanoscale, at very small dimensions. So this conference is now it's in 16th year, it started several years ago here in Greece as one day workshop and started growing because also nanotechnology started growing at the same time and now has become a multi faceted conference that attracts more than 600 people from all over the world. So 16 years ago was just one day workshop. And how long time did it take before it became grew like this? It started growing slowly probably it came to its current size maybe five years after it started converting to a conference and being publicized internationally as shots. And then currently as I said this in its peak we have added also a couple of other conferences that are taking place at the same time such as a conference on organic materials, on solar panels, on photonics. That was emerged and is offered in parallel with this conference. A summer school started also and it's taking place simultaneously where students, usually graduate students of the university are attending lectures that some of the participants at the conference provide and most of them again are related to nanotechnology and nanosciences. And although 16 years you were in Berkeley or? Yes, all these 16 years I was in Berkeley. But you often come to Greece or? I come every summer almost in Greece because my relatives are back here and I always come to this city, Thessaloniki, because we were spending our vacation in Khalkidiki. And also because in 1994, 1994 I met the professor Logothetidis who is the spearheader of this conference completely by accident and because we happen to have the same instrument and a company that wanted to provide some services to his instrument. He asked me if I could talk with him and explain to him the difference between my instrument and his instrument and so that's how I became acquainted with him. And after discussing our interests we found a lot of common interests in the nanoscale where at that time we didn't have even the term nanotechnology established. And that's why it became more of a workshop where a couple of people like me arriving in the same almost time frame here will give some lectures and some of the local people will join and make that a one day workshop. But as the time went by and the focus of internationally and the term of nanotechnology since the early of 2000 became more of an established name in a new field the workshop grew and became today what is known as international conference. In my view one of the top five conferences in nanotechnology. So what's the other four? There are other nanotechnologies in the world that are offered in various places or related to USA and mostly in the USA and maybe in Japan and China one or two more also. But none of this kind of breadth that we see here because like I said is two or three conferences merged together under the auspices of nanotechnology, nanosciences and summer school and that obviously makes it a very very big event. Plus the exposition that also adds about 30 to 40 booths various expositions that you can see on nanotechnology related topics. So are you co-founder of the conference or you came in after? There is no co-founder. I mean I was one of the first to sort of... The first one? Since the first one I have not missed one. I had among others suggested that we should publicize this more and make it more of international conference and I'm very happy to see that this happening. But the main person that is running the show is Professor Loko Thetidis who has made a tremendous job in really making that bringing that to the statue that is today. So it's one of the leading ones in Europe? Definitely it's probably the number one in Europe and like I said the one of the top four or five in the world. And so what do you do over there in Berkeley? So I work in mechanical, electrical, chemical and biochemical properties of surfaces. I'm in the surface science group, thin films. And so I'm concerned about all of these materials especially at the nanoscale. What kind of mechanical, electrical, optical, chemical and bio-physical characteristics they have. Specifically we're looking at very thin films, diamond like films as protective overcoats for next generation hard disk drives. We're looking into tissue formation from scaffolds, electrospinning of polymeric scaffolds and then impregnation with stem cells that we can trigger them to differentiate to various types of cells to create different types of tissues. We work in programs that related to manufacturing of wearable devices. These are devices that contain electronics but they have to be able to sustain large deformations as they are applied to our body. Like a forehead band or wrist band that can monitor your temperature and your heartbeat. So we're working on making these materials to be able to sustain these repetitive loadings. And also the electronics where they have to be strategically placed in locations where we can control and minimize the formation so that the electronic behavior is not jeopardized. We are also working in a new field of bonding of semiconductor materials by a purely mechanical process known as ultrasonic bonding. And a lot of work also goes into modeling of various contact problems. For example, imparting in simulation codes the properties and the morphology of surfaces. This can be the interface of a human artificial joint that we want to model and determine the stress and strains into this artificial implant which will then enable us to return and optimize the design and the properties of this implant. So we do a lot of computational analysis that goes along with the experiments. So this bonding with the semiconductors, how does that work? What does it do compared to what's there now? So the ultrasonic wire bonding is a process where we can connect with the conductive wire to boards, to electronic boards. The traditional way has been to do soldering. In this case you have to melt the wire and part of the substrate and introduce a soldering material. So you have three different materials that they have to weld together and also heat. All of these are creating problems to the circuitry and the cost of the bonding process. The ultrasonic wire bonding process essentially uses a tool that is vibrating to press against the wire and basically smear it over the board substrate and create therefore a mechanical bond by causing this wire to plastically deform and flow on the board surface. So it's completely solderness and temperature free process. Is it easy to do or is it very difficult to do? Every process has its own problems so we need to work to understand better how the bonding forms and how the wire as it is compressed and forced to flow on the substrate deforms plastically. So yeah, there are problems related with wire transfer material from the wire transferring of the bonding tool or wear of the bonding tool. So we're trying to solve these problems both from experiments and simulations. So if this works the PCB and the CPUs on the PCB and all that, all the electronics will change appearance? Well the bonding process will change definitely. The process is already in the market so we are funded by one of the companies that is pioneering this work. It has been around for 10 years and trying to become more competitive by solving the problems that come with that. For example extending the number of bonds that the tool can perform before it has to be cleaned or before it has to be replaced because of wear problems. And what about those hard drives? I'm always amazed by the amount of data I can put on them. So are you working on the next cutting edge, next things that are happening like the 3D layers and all this stuff and what they call the hammer or what they call it? Yes, so we're working on the hammer technology which stands for Heat Assisted Magnetic Recording. So the new generation of hard disk drives in order to be able to store more information and therefore have a higher storage capacity we are aiming to 10 terabits per square inch of area. It requires that we have very small magnetic domains in the magnetic medium that is deposited on the hard disk and on top of that a protective carbon overcoat to protect it from corrosion or wear if the head touches to that. As the science has advanced to the point that we can make these magnetic domains, the so-called bits into the magnetic layer of this hard disk smaller and smaller, we have come across to a physical limit known as the super paramagnetic limit. This teeny magnetic domains can no longer remain stable as they're magnetized with their north or south poles upwards representing zeros and ones because the information is stored in the binary form with zeros and ones. So these small magnetic domains tend to flip and that has necessitated to be to the technology to change them from a soft magnet which was easy for the magnetic head to flip and therefore polarize it differently every time that information needed to be written or erased to be made out of the so-called hard magnet. A hard magnet is a material that is stable because it requires a high intensity magnetic field in order to be changed and that magnetic field is not available by its neighboring small magnetic domains. It's not also available by the magnetic head that now cannot erase information and polarize again those magnetic bits. So here is where the term heat comes in and is related to the fact that a laser beam now is integrated with the magnetic head. Its purpose is to locally and instantaneously heat the magnetic domain, the bit, lowering its coercivity, its magnetic strength so that the magnetic head with its magnetic field can at the same time polarize it. And as the laser moves over the bit immediately cools down to room temperature and locks the new polarization and returns to its high coercivity strength, strong magnetic. So that obviously poses a lot of more stringent requirements to the protective overcoat that now has to sustain these heat pulses that is receiving from the head whenever information is needed to be locally retrieved, recorded or rewritten. So our work is to make these films not only thin and hard and smooth but also thermally stable. So we're studying with some advanced microscopy cross-section microscopy methods how this structure of these films retains its time like character when it's heated and it's not becoming graphic because that would be catastrophic for the protection of the head. And also the disc where they're both coated with this thin diamond like carbon overcoat. So when you have these things work then companies like Seagate might buy it from you, they sponsor it or something like that? We are currently funded heavily by Western Digital which is one of the pioneers and Seagate is of course one other bigger big competitor. We are working together with their team and we are providing the fundamental knowledge that will enable them to move faster to the next production and the next device that will have the hammer technology. And hammer is happening, it's already kind of shipping, right? It's already happening, it's already shipping but there are always challenges that would like to make this even more robust. Universities in the US are usually targeted by these big industries in anticipation of the forthcoming challenges as they're going to be trying to boost their products to the next generation. They need to acquire these basic knowledge ahead of time before this can happen. Is this nanotechnology? It is nanotechnology because the protective overcoat, the diamond like film that we're talking about, that we are synthesizing in my lab and then we characterize it is about one or two nanometers. So that's about one millionth of the diameter of the human hair. So you can understand the big challenges behind making those to be continuum so they don't form like islands that they then tend to merge as you get this coating thicker. But also they retain also their diamond like characteristics as they are heated. So the characterization is very challenging for very thin films and because of the nanometer size that they have, we have to use nanotechnology derived instruments like nano probes that we can poke these films and try to understand their mechanical properties without getting the effect of the substrate. Because you want the data to remain there and I find that totally amazing. You're talking about the space of two nanometers and that it just reliably stays there. I guess there's a lot of statistical kind of mathematics in there so there's redundancy and stuff in the way that hard drives are made. But is it completely different to how hard drives were made before? Some of the basic principles are the same but when I started working in this field the protective overcoat was half a micro that is 500 nanometers and now we're talking about one or two nanometers. So you can understand that we have two orders of magnitude decrease in the size of this overcoat. How long time to do this two orders of magnitude decrease? That happened over two decades, two and a half decades. It didn't happen immediately from 500 nanometers to two. It gradually came down and the motivation behind was to bring the magnetic transuser on the head as close as possible to the magnetic layer on the hard disk. Obviously because the magnetic domains were getting smaller since the densities that we were aiming for were increasing. And having these magnetic domains smaller required a more focused magnetic field. So you need to have the transuser on the magnetic head as close as possible if ideally theoretically I would say in contact with the magnetic layer. In order to individually polarize those magnetic domains. So this resulted in to reducing both the flying height of the head and also the thickness of the overcoat as they're both contributing to that distance. That is an obstacle to focus and enhance the magnetic field because it changes exponentially with the distance. So the intensity of this field we want to be as high as possible so that we can magnetize hard magnetic domains in the magnetic layer and also as close as possible to the magnetic head so that we can focus on a single bit. We don't want to polarize several bits at the same time. All this just sounds so awesome. I don't know how many 8 terabyte hard drives I have but if this all works out in the next couple years we might have 100 terabyte hard drives. It must be a really fascinating field to work in. Absolutely. So like I said the immediate goal is 10 terabits per square inch. That's a big hard drive. So currently you can get the whole drive to be about one terabit but I'm talking about 10 terabits per square inch. So you can get a drive today that is one and a quarter of an inch or two inches in diameter and that whole disk can be about one terabyte. Now we are talking about the square inch of that not the whole disk. The whole disk has a bunch of square inches. Yes. So you can make the math and see how many square inches is depending on the diameter. But usually in that field we go by the square inch and the cost is determined also by the square inch. So 20 years ago we had a few hundreds of megabytes per square inch. OK. And now we went to Terra which is 100 times more. We're talking about now we have demonstrated one or two terabytes per square inch. That's already in the market. We are aiming now one order higher 10 terabits per square inch. It has been always said that that the magnetic recording probably has reached saturation because you wouldn't be able to make such small domains or being able to individually polarize those domains if you were to make them. And that's where the nanotechnology comes because it provides the materials nano materials nano domains. We're talking about here and also the instrumentation to test those materials. The fabrication now of smaller heads. We have the so-called Pico heads Pico sliders Pico heads not nano heads yet and not nano. Well Pico is smaller than nano. Oh it is. Yes. So so the technology the nanotechnology provides really the tools that enable us to to reach this kind of materials. To accuracy in terms of their microstructure and thickness. But also the ability to maintain in such a close proximity a head that is flying at 10 meters per second over the disk. Someone made the following analogy which is easier to for the people that are not familiar to understand is like an F 16 flying at two max over a jungle and touching the higher tips of the higher trees. The tips of the higher trees. Without damaging the tree. Without damaging the tree and without being damaged itself if that can happen. So the sheer rates are very high of the head that is flying over the disk. And that's why and flying so close it may cause instantaneously some contact to take place between the head and the disk. That's why both the head and the disk are coated with this ultra thin diamond like carbon overcoat that I mentioned earlier. Which serves that purpose that is protecting both media to be damaged in case of an intimate contact that takes place. And of course the other protection that provides is corrosion resistance. How does it how's it possible to that it can read and write at two nanometers and so fast and all that stuff. Well now you're asking a question about the controls which is another area that has really improved dramatically. And that requires that you can control the position with a very fast feedback control that requires a suspension to first micro position the head over a given track. And then nano position the head over a given bit. So we have two stages of micro and nano positioning and control of the flying height that are based on feedback control. So all the control systems that are on the suspension of the head have also gone along the same journey with the materials and the mechanics in response to the requirements. It's a multi engineering problem that requires all many disciplines to be involved in that. That's so awesome and we just covered two of those you mentioned. You also mentioned stuff about the nano medicine right. Yes so we are interested in developing tissue. So we are creating this ponzi type of polymeric biodegradable materials that we then impregnate them with stem cells epithelial cells smooth muscle cells. I understand trying to understand how these cells can migrate into the porosity of this biodegradable material and begin to develop tissue. This scale is probably not as small as the previous ones but it still requires some understanding about cellular behavior. So we have developed a micro fabrication process where we can isolate individual cells on a platform and then use nano technology based force microscopy like the atomic force microscope. That enables us to poke press against these individual cells and determine their mechanical characteristics. For example we can also determine how they are different between a cancerous cell or a healthy cell. So the probe that we are using is an FM probe we are applying piconewton forces. So here is even one two orders of magnitude smaller than nano and we are using confocal microscopy to observe in real time how the cell is deforming and establish relationships between force and deformation of these cells and how this can be different between T cells and stem cells or cancerous cells. That begins to also provide some insight into biologists that relates to migration of cancerous cells. We have found for example that cancerous cells are softer than healthy cells. So that may be a reason, one of the reasons that they can more easily diffuse through the pores of the tissue and therefore migrate at different places. And are you doing this kind of analysis inside real people or just a bunch of tissue in a lab on the side? We are doing that at the lab scale. We have gone also to animal models where we have implanted these scaffolds per continuously into rats and retrieved them after a week or two weeks and then do the immunochemistry analysis to see what kind of reactions they have induced and whether they have induced the cells of the animal to migrate into that or not. All of these are also done at the animal stage. We have not gone to the clinical stage yet. That requires collaborations with the medical school. We have some ideas about that and perhaps collaborating with the University of California at San Francisco across the bay with the medical school they have if we reach that stage. Is it possible that things in that field could develop very quickly because people would like to see some results? That will depend on the outcome of the animal and clinical studies that are currently ongoing and of course FDA then approvals and all of these that takes quite some time. The fortunate or the good thing or the positive thing on that is that we are using FDA approved materials and that's a big plus because that usually takes a long time if you are introducing a new material. So it remains to be seen but I'm hopeful that we can make better and faster strives in the future. I wish I could ask you a bunch more but how about can I ask you, I guess you really enjoy your job right? This is my hobby and I feel fortunate that I get paid to do my hobby. It's the best job for me in the planet and I enjoy it very much. And all the stuff you're talking about is a lot of collaborators, a lot of students, is a lot of what? Absolutely, yes. As you can understand this multi-disciplinarity is here and that's why perhaps if one person is to be judged based on the department of the school that he or she are that's probably misleading if this person is in a leading school. Top schools usually work at the frontiers of technologies, today's technologies are multi-disciplinary and therefore not only the individual has to have knowledge beyond the classical areas of his or her discipline but also collaborations and being able to collaborate with people from completely different fields. And Berkeley is one of the, I guess one of the top in the world I guess, right? I mean it sounds like it, it could be. Well, I think people say Berkeley is very good school so I'm not the one who will make that but I think we are one of the good schools. Could you in any ways think or say how things could go faster? I say the biggest element here is funding. Just funding? Funding. If you have the funding then things can happen very fast. Not far from Berkeley, there's a lot of big funds. There's a lot of 100 billionaire companies, right? And maybe they don't know where to spend their money sometimes. That's true and that may be requiring a different outreach approach from both sides. It took for quite some time for this multi-disciplinarity to happen and even now you can see many institutions having barriers because people from one discipline they don't want to make the extra effort to educate themselves and connect with their next building neighbors. So you can imagine how bigger the problem is with going outside the academia if you consider also proprietary issues that companies are very cautious about. Yeah, in the US there's a lot of lawsuits. And so there's the lawsuits, there's IP, there's a copper, what do you call it, patents and all that stuff. But if let's say there was a few billion dollars to something you're sure that things could go much faster? Absolutely. And that's why we see some of the foundations like Zuckerman's and Chan, the founder of Facebook has now made several donations in institutions including Berkeley, Stanford and where they created an incubator by putting 600 million dollars for this kind of future. Research to be accelerated. And to accelerate is just put more students on to it or how does it work? It's one brings the other of course. It requires the infrastructure, the instrumentation but then the people that do all the work of course are students and guided by faculty. And so you cannot separate one of the other. Good students and good faculty and well equipped laboratories are needed plus good interaction with other laboratories, industry or hospitals. An integration of that level is required when we're talking about this type of research.