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2015 QS World University Rankings by Subject: KAIST's Chemical Engineering ranks 17th and 19th for Materials Science in the World
Chemical Engineering (1st in Korea)
1
MIT (US)
2
UC Berkeley (US)
3
Stanford University (US)
4
University of Cambridge (UK)
5
National University of Singapore (Singapore)
17
KAIST (Korea)
Materials Science and Engineering (1st in Korea)
1
MIT (US)
2
Stanford University (US)
3
UC Berkeley (US)
4
University of Cambridge (UK)
5
North Western University (US)
19
KAIST (Korea)
Electrical and Electronic Engineering (1st in Korea)
1
MIT (US)
2
Stanford University (US)
3
UC Berkeley (US)
4
Harvard University (US)
5
ETH Zurich – Swiss Federal Institute of Technology (Switzerland)
22
KAIST (Korea)
Civil and Structural Engineering (1st in Korea)
1
MIT (US)
2
Delft University of Technology (The Netherlands)
3
National University of Singapore (Singapore)
4
Imperial College London (UK)
5
University of Cambridge (UK)
22
KAIST (Korea)
Mechanical, Aeronautical and Manufacturing Engineering (1st in Korea)
1
MIT (US)
2
Stanford University (US)
3
University of Cambridge (UK)
4
UC Berkeley (US)
5
Michigan University (US)
26
KAIST (Korea)
Chemistry (2nd in Korea)
1
MIT (US)
2
UC Berkeley (US)
3
University of Cambridge (UK)
4
Harvard University (US)
5
University of Oxford (UK)
26
KAIST (Korea)
Computer Science and Information Systems (1st in Korea)
1
MIT (US)
2
Stanford University (US)
3
University of Oxford (UK)
4
Carnegie Mellon University (US)
Harvard University (US)
39
KAIST (Korea)
The QS World University Rankings released its 2015 rankings by subject on April 29, 2015.
According to the rankings, KAIST’s Chemical and Biomolecular Engineering and Materials Science Engineering were listed in the top 20 global universities, 17th and 19th, respectively.
KAIST took first place in six subjects among Korean universities, including electrical and electronic engineering; civil and structural engineering; mechanical, aeronautical and manufacturing engineering; and computer science and information systems.
The QS World University Rankings by Subject highlights the world’s top universities in a range of popular subject areas, covering 36 subjects as of this year. Published annually since 2011, the rankings are based on academic reputation, employer reputation, citation count, and research impact.
For a full list of the rankings: http://www.topuniversities.com/subject-rankings/2015
2015.04.29 View 5927 -
KAIST Connects CNU with Pedestrian Walkway
KAIST and Chungnam National University (CNU) built a pedestrian walkway ("pedway") that physically brings them closer than ever. Opened on April 13, 2015, the KAIST-CNU Pedway now offers members of the two universities a quick and scenic road to walk or bike for their campus visit.
The 180-meter-strip, with a width of four meters, starts from KAIST’s student dormitories, Narae and Mir Halls, and arrives at the backyard of the College of Agriculture and Life Sciences building at CNU. For security and safety precaution, emergency alarms, CCTVs and security lights are installed along the path.
A commemorative event celebrating the opening of the pedway was held on April 15, 2015 at the KAIST campus. Along with senior administrators of the two universities, In-Sik Kim, Chairman of Daejeon City Assembly, Choon-Hee Baek, Deputy Mayor for Political Affairs of Daejeon, President Steve Kang of KAIST, and President Sang-Chul Jung of CNU will attend the event.
CNU is located just a twenty-minute walk from KAIST, but the two universities have had little interaction. To promote more collaboration and exchange, KAIST and CNU signed a memorandum of understanding on the cooperation of education, research, and medicine in June 2014.
With the KAIST-CNU Pedway as the stepping stone, the two universities will strengthen their cooperation in academic information exchange allowing access to their libraries and establishing the Graduate School of Integrated Medical Science in Sejong.
President Kang said, “Universities should not be isolated islands from the local community, but should act as bridges between different districts.” He continued, “I hope this pedway can be the starting point.”
President Jung said, “I hope this road can remove the wall between KAIST and Chungnam National University, in terms of knowledge, information, and people. I further hope that it will become the symbol and token of unity of the two universities.”
2015.04.13 View 7728 -
Novel Photolithographic Technology Enabling 3D Control over Functional Shapes of Microstructures
Professor Shin-Hyun Kim and his research team in the Department of Chemical and Biomolecular Engineering at KAIST have developed a novel photolithographic technology enabling control over the functional shapes of micropatterns using oxygen diffusion.
The research was published online in the March 13th issue of Nature Communications and was selected as a featured image for the journal.
Photolithography is a standard optical process for transferring micropatterns on to a substrate by exposing specific regions of the photoresist layer to ultraviolet (UV) light. It is used widely throughout industries that require micropatterns, especially in the semiconductor manufacturing industry.
Conventional photolithography relied on photomasks which protected certain regions of the substrate from the input UV light. Areas covered by the photomasks remain intact with the base layer while the areas exposed to the UV light are washed away, thus creating a micropattern. This technology was limited to a two-dimensional, disc-shaped design as the boundaries between the exposed and roofed regions are always in a parallel arrangement with the direction of the light.
Professor Kim’s research team discovered that: 1) the areas exposed to UV light lowered the concentration of oxygen and thus resulted in oxygen diffusion; and 2) manipulation of the diffusion speed and direction allowed control of the growth, shape and size of the polymers. Based on these findings, the team developed a new photolithographic technology that enabled the production of micropatterns with three-dimensional structures in various shapes and sizes.
Oxygen was considered an inhibitor during photopolymerization. Photoresist under UV light creates radicals which initialize a chemical reaction. These radicals are eliminated with the presence of oxygen and thus prevents the reaction. This suggests that the photoresist must be exposed to UV light for an extended time to completely remove oxygen for a chemical reaction to begin.
The research team, however, exploited the presence of oxygen. While the region affected by the UV light lowered oxygen concentration, the concentration in the untouched region remained unchanged. This difference in the concentrations caused a diffusion of oxygen to the region under UV light.
When the speed of the oxygen flow is slow, the diffusion occurs in parallel with the direction of the UV light. When fast, the diffusion process develops horizontally, outward from the area affected by the UV light. Professor Kim and his team proved this phenomenon both empirically and theoretically. Furthermore, by injecting an external oxygen source, the team was able to manipulate diffusion strength and direction, and thus control the shape and size of the polymer. The use of the polymerization inhibitors enabled and facilitated the fabrication of complex, three-dimensional micropatterns.
Professor Kim said, “While 3D printing is considered an innovative manufacturing technology, it cannot be used for mass-production of microscopic products. The new photolithographic technology will have a broad impact on both the academia and industry especially because existing, conventional photolithographic equipment can be used for the development of more complex micropatterns.” His newest technology will enhance the manufacturing process of three-dimensional polymers which were considered difficult to be commercialized.
The research was also dedicated to the late Professor Seung-Man Yang of the Department of Chemical and Biomolecular Engineering at KAIST. He was considered one of the greatest scholars in Korea in the field of hydrodynamics and colloids.
Picture 1: Featured Image of Nature Communications, March 2015
Picture 2: Polymers with various shapes and sizes produced with the new photolithographic technology developed by Professor Kim
2015.04.06 View 10785 -
ITTP Produces 119 Graduates from 52 Countries.
“Transparency of Costa Rica was highly improved after adopting an electronic purchase and supply system from Korea.”
So noted a public official from the technical office of the digital government in Costa Rica, Ileana Palaco, who entered the master’s program in KAIST’s Global Information and Telecommunication Technology Program (ITTP) last September.
She also said, “The electronic government of Korea is an exemplary model emulated in the establishment of the e-Government system in Central and South America. I am eager to introduce Korean IT technology and policies to the countries in the region.”
Consisting of master’s and doctoral programs designed for public officials and technical experts in emerging countries, ITTP fosters international cooperation, builds human networks, and supports domestic companies in technology transfers.
For the past twenty years, the IT industry has been the key to Korea’s development. Utilizing its advancement in the IT technology, Korea provides developing countries with the support necessary for their continuous growth in the 21st century. To that end, KAIST created ITTP which invites government officials from emerging countries with a growing IT industry.
Run by the Business and Technology Management Department of KAIST since 2006, ITTP has produced 119 graduates from 52 countries. For the past 10 years, 57 students from Africa, 45 from South East-Asia, 16 from Eastern Europe, and 7 from the Middle East were accepted to the program.
The program consists of theory-based classes which introduces the technology and IT policies of Korea and project-based classes for university-industry cooperation. In the latter, experts from professional organizations in IT such as the Electronics and Telecommunications Research Institute (ETRI), the National Information Society Agency (NIA), and Korea Telecom participate and provide information based on industry experience.
Foreign governments and international organizations have reacted positively to this program. Having recognized its excellence, the International Telecommunication Union (ITU) has supported it by sending the application information to 193 member countries. The African Development Bank (AFDB) chose ITTP as one of the Next Generation African Leadership Programs and assigned 19 public officials from Africa.
ITTP graduates have played a large role in promoting the e-Government system overseas. In In 25 cases in 2012, graduates participated as researchers in 6 cases. Thanks to the support of elite public officials from emerging countries who graduated from ITTP, Korean technology companies can bring their technology to overseas countries more effectively.
Recently, government officials from these countries have been asking for both long and short- term programs on technology and IT policies. In response, KAIST is planning to expand the program. Professor Jaejeung Rho from the Business and Technology Management Department who supervises this program said, “Allowing public officials in the field of IT all over the world to know more about Korea is very important in raising Korea’s reputation in technology and in the globe” and added that “having these officials is a boon in keeping our country’s competitive edge in the IT industry.”
Picture: About 60 people including ITTP students, the Nigerian ambassador to Korea, and President Steve Kang of KAIST joined a ceremony to raise a scholarship fund for KAIST on April 2, 2015 at Munji campus in Daejeon.
2015.04.03 View 8189 -
Mystery in Membrane Traffic How NSF Disassembles Single SNAR Complex Solved
KAIST researchers discovered that the protein N-ethylmaleimide-sensitive factor (NSF) unravels a single SNARE complex using one round ATP turnover by tearing the complex with a single burst, contradicting a previous theory that it unwinds in a processive manner.
In 2013, James E. Rothman, Randy W. Schekman, and Thomas C. Südhof won the Nobel Prize in Physiology or Medicine for their discoveries of molecular machineries for vesicle trafficking, a major transport system in cells for maintaining cellular processes. Vesicle traffic acts as a kind of “home-delivery service” in cells. Vesicles package and deliver materials such as proteins and hormones from one cell organelle to another. Then it releases its contents by fusing with the target organelle’s membrane. One example of vesicle traffic is in neuronal communications, where neurotransmitters are released from a neuron. Some of the key proteins for vesicle traffic discovered by the Nobel Prize winners were N-ethylmaleimide-sensitive factor (NSF), alpha-soluble NSF attachment protein (α-SNAP), and soluble SNAP receptors (SNAREs).
SNARE proteins are known as the minimal machinery for membrane fusion. To induce membrane fusion, the proteins combine to form a SNARE complex in a four helical bundle, and NSF and α-SNAP disassemble the SNARE complex for reuse. In particular, NSF can bind an energy source molecule, adenosine triphosphate (ATP), and the ATP-bound NSF develops internal tension via cleavage of ATP. This process is used to exert great force on SNARE complexes, eventually pulling them apart. However, although about 30 years have passed since the Nobel Prize winners’ discovery, how NSF/α-SNAP disassembled the SNARE complex remained a mystery to scientists due to a lack in methodology.
In a recent issue of Science, published on March 27, 2015, a research team, led by Tae-Young Yoon of the Department of Physics at the Korea Advanced Institute of Science and Technology (KAIST) and Reinhard Jahn of the Department of Neurobiology of the Max-Planck-Institute for Biophysical Chemistry, reports that NSF/α-SNAP disassemble a single SNARE complex using various single-molecule biophysical methods that allow them to monitor and manipulate individual protein complexes.
“We have learned that NSF releases energy in a burst within 20 milliseconds to “tear” the SNARE complex apart in a one-step global unfolding reaction, which is immediately followed by the release of SNARE proteins,” said Yoon.
Previously, it was believed that NSF disassembled a SNARE complex by unwinding it in a processive manner. Also, largely unexplained was how many cycles of ATP hydrolysis were required and how these cycles were connected to the disassembly of the SNARE complex.
Yoon added, “From our research, we found that NSF requires hydrolysis of ATPs that were already bound before it attached to the SNAREs—which means that only one round of an ATP turnover is sufficient for SNARE complex disassembly. Moreover, this is possible because NSF pulls a SNARE complex apart by building up the energy from individual ATPs and releasing it at once, yielding a “spring-loaded” mechanism.”
NSF is a member of the ATPases associated with various cellular activities family (AAA+ ATPase), which is essential for many cellular functions such as DNA replication and protein degradation, membrane fusion, microtubule severing, peroxisome biogenesis, signal transduction, and the regulation of gene expression. This research has added valuable new insights and hints for studying AAA+ ATPase proteins, which are crucial for various living beings.
The title of the research paper is “Spring-loaded unraveling of a single SNARE complex by NSF in one round of ATP turnover.” (DOI: 10.1126/science.aaa5267)
Youtube Link: https://www.youtube.com/watch?v=FqTSYHtyHWE&feature=youtu.be
Picture 1. Working model of how NSF/α-SNAP disassemble a single SNARE complex
Picture 2. After neurotransmitter release, NSF disassembles a single SNARE complex using a single round of ATP turnover in a single burst reaction.
2015.03.28 View 11024 -
Mutations Occurring Only in Brain Responsible for Intractable Epilepsy Identified
KAIST researchers have discovered that brain somatic mutations in MTOR gene induce intractable epilepsy and suggest a precision medicine to treat epileptic seizures.
Epilepsy is a brain disorder which afflicts more than 50 million people worldwide. Many epilepsy patients can control their symptoms through medication, but about 30% suffer from intractable epilepsy and are unable to manage the disease with drugs. Intractable epilepsy causes multiple seizures, permanent mental, physical, and developmental disabilities, and even death. Therefore, surgical removal of the affected area from the brain has been practiced as a treatment for patients with medically refractory seizures, but this too fails to provide a complete solution because only 60% of the patients who undergo surgery are rendered free of seizures.
A Korean research team led by Professor Jeong Ho Lee of the Graduate School of Medical Science and Engineering at the Korea Advanced Institute of Science and Technology (KAIST) and Professor Dong-Seok Kim of Epilepsy Research Center at Yonsei University College of Medicine has recently identified brain somatic mutations in the gene of mechanistic target of rapamycin (MTOR) as the cause of focal cortical dysplasia type II (FCDII), one of the most important and common inducers to intractable epilepsy, particularly in children. They propose a targeted therapy to lessen epileptic seizures by suppressing the activation of mTOR kinase, a signaling protein in the brain. Their research results were published online in Nature Medicine on March 23, 2015.
FCDII contributes to the abnormal developments of the cerebral cortex, ranging from cortical disruption to severe forms of cortical dyslamination, balloon cells, and dysplastic neurons. The research team studied 77 FCDII patients with intractable epilepsy who had received a surgery to remove the affected regions from the brain. The researchers used various deep sequencing technologies to conduct comparative DNA analysis of the samples obtained from the patients’ brain and blood, or saliva. They reported that about 16% of the studied patients had somatic mutations in their brain. Such mutations, however, did not take place in their blood or saliva DNA.
Professor Jeong Ho Lee of KAIST said, “This is an important finding. Unlike our previous belief that genetic mutations causing intractable epilepsy exist anywhere in the human body including blood, specific gene mutations incurred only in the brain can lead to intractable epilepsy. From our animal models, we could see how a small fraction of mutations carrying neurons in the brain could affect its entire function.”
The research team recapitulated the pathogenesis of intractable epilepsy by inducing the focal cortical expression of mutated mTOR in the mouse brain via electroporation method and observed as the mouse develop epileptic symptoms. They then treated these mice with the drug called “rapamycin” to inhibit the activity of mTOR protein and observed that it suppressed the development of epileptic seizures with cytomegalic neurons.
“Our study offers the first evidence that brain-somatic activating mutations in MTOR cause FCDII and identifies mTOR as a treatment target for intractable epilepsy,” said co-author Dr. Dong-Seok Kim, a neurosurgeon at Yonsei Medical Center with the country’s largest surgical experiences in treating patients with this condition.
The research paper is titled “Brain somatic mutations in MTOR cause focal cortical dysplasia type II leading to intractable epilepsy.” (Digital Object Identifier #: 10.1038/nm.3824)
Picture 1: A schematic image to show how to detect brain specific mutation using next-generation sequencing technology with blood-brain paired sample. Simple comparison of non-overlapping mutations between affected and unaffected tissues is able to detect brain specific mutations.
Picture 2: A schematic image to show how to generate focal cortical dysplasia mouse model. This mouse model open the new window of drug screening for seizure patients.
Picture 3: Targeted medicine can rescue the focal cortical dysplasia symptoms including cytomegalic neuron & intractable epilepsy.
2015.03.25 View 14408 -
KAIST Alumni Awards Academic Scholarships
The KAIST Alumni Academic Scholarship Foundation awarded scholarships to 25 KAIST students. The award ceremony took place on March 15, 2015, in Seoul.
The Foundation selected 21 Korean students and four foreign students based on their leadership skills and academic achievements. Each Korean student received USD 3,600, and each international student USD 900. The scholarships will be provided to the students for up to three years.
The Foundation allows alumni whose donations surpass a certain threshold amount to name their scholarships. This year, a total of eleven donors used this service.
The Foundation provided scholarships to 25 students in 2004 as well.
2015.03.20 View 6973 -
KAIST Exhibits Socially Benign Technologies
Exhibited 29 products that address the need to solve social issues such as a Braille printer
Students from the KAIST Idea Factory, a startup program for undergraduates operated by the Research Institute for Social Technology and Innovation (RISTI), hosted an exhibition presenting their research prototypes. The Idea Factory provides students with opportunities to try out new ideas and develop innovative technologies.
The exhibition was held at the Creative Learning building on campus on March 20, 2015. Students displayed 29 inventions, showcasing technologies to address important social issues. The exhibit included products and technologies developed by the students or already commercialized by small businesses such as a Braille printer, a hydrogen peroxide-oxygen respirator for vessel accidents, and an educational 3D printer. The small business exhibits included a removable additional power unit for wheelchairs, agricultural product anti-theft system, and security lighting.
KAIST also hosted a social technology innovation symposium in KAIST Institute Building on the same day. The theme of the symposium was the “Integration of Technological Innovation and Social Innovation – Social Technology Innovation.”
The key note speaker, Director Heung-Kyu Lee of RISTI, KAIST, presented a lecture on the topic, “The Meaning of Social Technology Innovation: System Change.” His talk was followed by Hyuk-Jin Choi of the Korea Social Enterprise Promotion Agency on “Social Economic Organizations of Korea and Social Technology,” and Jae-Sun Kim of The Grassroots on “Search for Social Innovation and Social Economy.”
The supervisor of the event, Director Lee said, “This exhibit focuses on technologies that could help the underprivileged. We will continue to support students’ ideas and small businesses’ endeavors to develop these technologies.”
KAIST established the Idea Factory in 2014 to assist KAIST students to commercialize creative and innovative ideas. The Idea Factory made a key contribution in commercializing the educational 3D printers last year.
Picture: A Braille Printer
2015.03.20 View 7525 -
Qualcomm Innovation Award Recognizes 20 KAIST Students
The
award provides research fellowships, worth of USD 100,000, to 20 KAIST graduate
students
With an audience of 100 people present,
KAIST held a ceremony for the Qualcomm Innovation Award 2015 at the Information
Technology Convergence building on campus on March 12, 2015.
The Qualcomm Innovation Award, established
in 2010, is a fellowship that supports innovative science and engineering master’s
and doctoral students at KAIST. Qualcomm donated USD 100,000 to KAIST, stipulating that it be used to foster a creative research environment for graduate
students.
To select the recipients, KAIST formed an award committee chaired
by Professor Soo-Young Lee of the Department of Electrical Engineering and accepted research proposals until late January.
The award committee first selected 37
proposals from 75 papers submitted and then chose the final 20 research
proposals on March 12, 2015 after presentation evaluations. The presentations had to show promise of innovation and creativity; prospective influence on wireless communications
and mobile industry; and the prospect of being implemented.
Each recipient received a USD 4,500 research
fellowship along with an opportunity to present their research findings at a
workshop where Qualcomm engineers and other distinguished individuals of the industry
will attend.
Previously, Qualcomm has donated
research fellowships to KAIST graduate students in 2011 and 2013.
2015.03.19 View 10317 -
Professor Sangyong Jon Appointed Fellow of AIMBE
Professor Sangyong Jon of the Department of Biological Sciences at KAIST has been appointed a member of the American Institute for Medical and Biological Engineering (AIMBE) fellowship.
Established in 1991, AIMBE is a non-profit organization based in Washington, D.C., representing 50,000 individuals and the top 2% of medical and biological engineers. AIMBE provides policy advice and advocacy for medical and biological engineering for the benefit of humanity. It has had about 1,500 fellows over the past 25 years. Among the members, only 110 are non-American nationalities.
Following the appointment of Dr. Hae-Bang Lee, the former senior researcher at the Korean Research Institute of Chemical Technology, and Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering at KAIST, Professor Jon is the third Korean to become an AIMBE fellow. He had an induction ceremony for the appointment of his fellowship at the AIMBE’s Annual Event held on March 15-17, 2015 in Washington, D.C.
An authority on nanomedicine, Professor Jon has developed many original technologies including multi-functional Theranostics nano particles for the diagnosis and treatment of diseases. He received the Most Cited Paper Award from Theranostics, an academic journal specialized in nanomedicine, last February.
Additionally, Professor Jon is a leading researcher in the field of translational medicine, using a multi-disciplinary, highly collaborative, “Bench to Bedside” approach for disease treatment and prevention. He created a biotechnology venture company and transferred research developments to the industry in Korea.
2015.03.12 View 12916 -
KAIST Develops Ultrathin Polymer Insulators Key to Low-Power Soft Electronics
Using an initiated chemical vapor deposition technique, the research team created an ultrathin polymeric insulating layer essential in realizing transistors with flexibility and low power consumption. This advance is expected to accelerate the commercialization of wearable and soft electronics.
A group of researchers at the Korea Advanced Institute of Science and Technology (KAIST) developed a high-performance ultrathin polymeric insulator for field-effect transistors (FETs). The researchers used vaporized monomers to form polymeric films grown conformally on various surfaces including plastics to produce a versatile insulator that meets a wide range of requirements for next-generation electronic devices. Their research results were published online in Nature Materials on March 9th, 2015.
FETs are an essential component for any modern electronic device used in our daily life from cell phones and computers, to flat-panel displays. Along with three electrodes (gate, source, and drain), FETs consist of an insulating layer and a semiconductor channel layer. The insulator in FETs plays an important role in controlling the conductance of the semiconductor channel and thus current flow within the translators. For reliable and low-power operation of FETs, electrically robust, ultrathin insulators are essential. Conventionally, such insulators are made of inorganic materials (e.g., oxides and nitrides) built on a hard surface such as silicon or glass due to their excellent insulating performance and reliability.
However, these insulators were difficult to implement into soft electronics due to their rigidity and high process temperature. In recent years, many researchers have studied polymers as promising insulating materials that are compatible with soft unconventional substrates and emerging semiconductor materials. The traditional technique employed in developing a polymer insulator, however, had the limitations of low surface coverage at ultra-low thickness, hindering FETs adopting polymeric insulators from operating at low voltage.
A KAIST research team led by Professor Sung Gap Im of the Chemical and Biomolecular Engineering Department and Professor Seunghyup Yoo and Professor Byung Jin Cho of the Electrical Engineering Department developed an insulating layer of organic polymers, “pV3D3,” that can be greatly scaled down, without losing its ideal insulating properties, to a thickness of less than 10 nanometers (nm) using the all-dry vapor-phase technique called the “initiated chemical vapor deposition (iCVD).”
The iCVD process allows gaseous monomers and initiators to react with each other in a low vacuum condition, and as a result, conformal polymeric films with excellent insulating properties are deposited on a substrate. Unlike the traditional technique, the surface-growing character of iCVD can overcome the problems associated with surface tension and produce highly uniform and pure ultrathin polymeric films over a large area with virtually no surface or substrate limitations. Furthermore, most iCVD polymers are created at room temperature, which lessens the strain exerted upon and damage done to the substrates.
With the pV3D3 insulator, the research team built low-power, high-performance FETs based on various semiconductor materials such as organics, graphene, and oxides, demonstrating the pV3D3 insulator’s wide range of material compatibility. They also manufactured a stick-on, removable electronic component using conventional packaging tape as a substrate. In collaboration with Professor Yong-Young Noh from Dongguk University in Korea, the team successfully developed a transistor array on a large-scale flexible substrate with the pV3D3 insulator.
Professor Im said, “The down-scalability and wide range of compatibility observed with iCVD-grown pV3D3 are unprecedented for polymeric insulators. Our iCVD pV3D3 polymeric films showed an insulating performance comparable to that of inorganic insulating layers, even when their thickness were scaled down to sub-10 nm. We expect our development will greatly benefit flexible or soft electronics, which will play a key role in the success of emerging electronic devices such as wearable computers.”
The title of the research paper is “Synthesis of ultrathin polymer insulating layers by initiated chemical vapor deposition for low-power soft electronics” (Digital Object Identifier (DOI) number is 10.1038/nmat4237).
Picture 1: A schematic image to show how the initiated chemical vapor deposition (iCVD) technique produces pV3D3 polymeric films: (i) introduction of vaporized monomers and initiators, (ii) activation of initiators to thermally dissociate into radicals, (iii) adsorption of monomers and initiator radicals onto a substrate, and (iv) transformation of free-radical polymerization into pV3D3 thin films.
Picture 2: This is a transistor array fabricated on a large scale, highly flexible substrate with pV3D3 polymeric films.
Picture 3: This photograph shows an electronic component fabricated on a conventional packaging tape, which is attachable or detachable, with pV3D3 polymeric films embedded.
2015.03.10 View 13622 -
The Real Time Observation of the Birth of a Molecule
From right to left: Dr. Kyung-Hwan Kim, Professor Hyotcherl Lhee, and Jong-Gu Kim, a Ph.D. candidate
Professor Hyotcherl Lhee of the Department of Chemistry at KAIST and Japanese research teams jointly published their research results showing that they have succeeded in the direct observation of how atoms form a molecule in the online issue of Nature on February 19, 2015.
The researchers used water in which gold atoms ([Au(CN) 2- ]) are dissolved and fired X-ray pulses over the specimen in femtosecond timescales to study chemical reactions taking place among the gold atoms. They were able to examine in real time the instant process of how gold atoms bond together to become a molecule, to a trimer or tetramer state.
This direct viewing of the formation of a gold trimer complex ([Au(CN) 2- ] 3 ) will provide an opportunity to understand complex chemical and biological systems.
For details, please see the following press release that was distributed by the High Energy Accelerator Research Organization, KEK, in Japan:
Direct Observation of Bond Formations
February 18, 2015
A collaboration between researchers from KEK, the Institute for Basic Science (IBS), the Korea Advanced Institute of Science and Technology (KAIST), RIKEN, and the Japan Synchrotron Radiation Research Institute (JASRI) used the SACLA X-ray free electron laser (XFEL) facility for a real time visualization of the birth of a molecular that occurs via photoinduced formation of a chemical bonds. This achievement was published in the online version of the scientific journal “Nature” (published on 19 February 2015).
Direct “observation” of the bond making, through a chemical reaction, has been longstanding dream for chemists. However, the distance between atoms is very small, at about 100 picometer, and the bonding is completed very quickly, taking less than one picosecond (ps). Hence, previously, one could only imagine the bond formation between atoms while looking at the chemical reaction progressing in the test-tube.
In this study, the research group focused on the process of photoinduced bond formation between gold (Au) ions dissolved in water. In the ground state (S 0 state in Fig. 1) Au ions that are weakly bound to each other by an electron affinity and aligned in a bent geometry. Upon a photoexcitation, the S 0 state rapidly converts into an excited (S 1 state in Fig. 1) state where Au-Au covalent bonds are formed among Au ions aligned in a linear geometry. Subsequently, the S 1 state transforms to a triplet state (T 1 state in Fig. 1) in 1.6 ps while accompanying further contraction of Au-Au bonds by 0.1 Å. Later, the T 1 state of the trimer converts to a tetramer (tetramer state in Fig. 1) on nanosecond time scale. Finally, the Au ions returned to their original loosely interacting bent structure.
In this research, the direct observation of a very fast chemical reaction, induced by the photo-excitation, was succeeded (Fig. 2, 3). Therefore, this method is expected to be a fundamental technology for understanding the light energy conversion reaction. The research group is actively working to apply this method to the development of viable renewable energy resources, such as a photocatalysts for artificial photosynthesis using sunlight.
This research was supported by the X-ray Free Electron Laser Priority Strategy Program of the MEXT, PRESTO of the JST, and the the Innovative Areas "Artificial Photosynthesis (AnApple)" grant from the Japan Society for the Promotion of Science (JSPS).
Publication: Nature , 518 (19 February 2015)
Title: Direct observation of bond formation in solution with femtosecond X-ray scattering
Authors: K. H. Kim 1 , J. G. Kim 1 , S. Nozawa 1 , T. Sato 1 , K. Y. Oang, T. W. Kim, H. Ki, J. Jo, S. Park, C. Song, T. Sato, K. Ogawa, T. Togashi, K. Tono, M. Yabashi, T. Ishikawa, J. Kim, R. Ryoo, J. Kim, H. Ihee, S. Adachi. ※ 1: These authors contributed equally to the work.
DOI: 10.1038/nature14163
Figure 1. Structure of a gold cyano trimer complex (Au(CN) 2 - ) 3 .
Figure 2. Observed changes in the molecular structure of the gold complex
Figure 3. Schematic view of the research of photo-chemical reactions by the molecular movie
2015.02.27 View 12760