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News Article | September 1, 2016
Site: phys.org

DGIST announced on Tuesday August 2, 2016 that Professor Choi Hong-soo's research team from the Department of Robotics Engineering developed ciliary microrobots with high propulsion efficiency in highly-viscous fluid environments in the human body such as blood by mimicking the movement of paramecia's cilia. Professor Choi's research team succeeded in fabricating the world's first ciliary microrobots utilizing ultra-fine three-dimensional processing technology and asymmetric magnetic drive technology by applying microorganism's ciliary movement, which thus far had only been theorized but never put into practice. Microfluidic environments in which microorganisms move include highly viscous environments like the human body's internal fluids; thus, in a macro environment, it is difficult to create propulsion with swimming-based mechanisms such as inertia-based symmetrical rowing like that used by large animals such as humans. As such, microorganisms moving in highly-viscous environments utilize various other propulsion techniques such as spiral drive motion, progressive wave motion, ciliary asymmetric reciprocating motion, and the like. Microrobots that use propulsion mechanisms such as spiral drive motion and progressive wave motion were first realized and implemented at the Zurich Federal Institute of Technology, Switzerland; University of Twente, Netherlands; and Harvard University, USA. However, the development of microrobots that move utilizing ciliary motion has thus far been absent due to the difficulty of producing a microstructure with a large number of cilia as well as with asymmetrical drive. Professor Choi's research team has produced a ciliary microrobot with nickel and titanium coating on top of photo-curable polymer material, using three-dimensional laser process technology and precise metal coating techniques. In addition, the team verified that the speed and propulsion efficiency of their newly-developed microrobots were much higher than those of existing conventional microrobots moving under magnetic attraction drive after measuring the ciliary microrobots' movement utilizing asymmetrical magnetic actuation technology. The maximum speed of ciliary microrobots with a length of 220 micrometers and a height of 60 micrometers is 340 micrometers per second, thus they can move at least 8.6 times faster and as much as 25.8 times faster than conventional microrobots moving under magnetic attraction drive. In comparison to previously developed microrobots, Professor Choi's ciliary microrobots are expected to deliver higher amounts of chemicals and cells to target areas in the highly viscous body environment thanks to their ability to freely change direction and to move in an 80 micrometer-diameter sphere to the target point shown in the experiment using the magnetic field. Professor Choi from DGIST's Department of Robotics Engineering said, "With precise three-dimensional fabrication techniques and magnetic control technology, my team has developed microrobots mimicking cilia's asymmetric reciprocation movement, which has been never realized so far. We'll continually strive to study and experiment on microrobots that can efficiently move and operate in the human body, so that they can be utilized in chemical and cell delivery as well as in non-invasive surgery." Explore further: 'Brobots': Sperm-inspired robots controlled by magnetic fields may be useful for drug delivery, IVF, cell sorting More information: Sangwon Kim et al. Fabrication and Manipulation of Ciliary Microrobots with Non-reciprocal Magnetic Actuation, Scientific Reports (2016). DOI: 10.1038/srep30713


News Article | February 17, 2017
Site: www.eurekalert.org

Many building processes still involve sub-standard working conditions and are not compellingly sustainable. Current research on the integration of digital technologies within construction processes promises substantial contributions to sustainability and productivity, while at the same time enabling completely new forms of architectural expression. The multidisciplinary nature of integrating digital processes remains a key challenge to establishing a digital building culture. In order to fully exploit the potential of digital fabrication, an institutional and funding environment that enables strong interdisciplinary research is required. Traditionally separated disciplines such as: architecture, structural design, computer science, materials science, control systems engineering, and robotics now need to form strong research connections. During the AAAS 2017 Annual Meeting in Boston, Jonas Buchli, ETH Zurich - The Swiss Federal Institute of Technology in Zurich, Switzerland, Ronald Rael, University of California, Berkeley, U.S.A., and Jane Burry, RMIT University, Melbourne, Australia reveal the latest developments in digital fabrication in architecture at 1:1 building scale. In their presentations, they show digital technologies can be successfully integrated in design, planning, and building processes in order to successfully transform the building industry. Jonas Buchli, Assistant Professor for Agile and Dexterous Robotics at ETH Zurich in Switzerland and principal investigator in the Swiss National Centre of Competence in Research (NCCR) Digital Fabrication is proposing a radical focus on domain specific robotic technology enabling the use of digital fabrication directly on construction sites and in large scale prefabrication. He demonstrates how researchers at ETH Zurich within the NCCR Digital Fabrication - Switzerland's leading initiative for the development and integration of digital technologies within the field of architecture - are facing the challenge of developing this technology. They bring a comprehensive and interdisciplinary approach that incorporates researchers from architecture, materials science, and robotics. In his presentation, Buchli will provide insight into current research and the future vision and development of the In situ Fabricator, a mobile and versatile construction robot, which in 2017 will be utilized for the first time on an actual building site. Digital computation has freed designers from the constraints of the static 2- and 3- dimensional representational techniques of drawing and physical modelling. Design attributes can be directly linked to extraneous factors: structural or environmental optimization, or fabrication and material constraints. Mathematical design models contain sufficient information even for computer numerical controlled (CNC) fabrication ma-chines and techniques. Jane Burry, Director of the Spatial Information Architecture Laboratory at RMIT University in Melbourne, Australia, explores how these opportunities for automation, optimization, variation, mass-customization, and quality control can be fully realized in the built environment within full scale construction. Burry shows select digital fabrication examples, where research and innovation have changed construction practice. She will draw on prominent case studies such as the design and construction of Antonio Gaudí's Sagrada Familia. Most materials currently used in 3D printing, were developed to print small scale objects. Ronald Rael, Associate Professor for Architecture at University of California, Berkeley, U.S.A., reveals how he is developing new materials that can overcome the challenges of scale and costs of 3D printing on 1:1 construction scale. He demonstrates that viable solutions for 3D printing in architecture involve a material supply from sustainable resources, culled from waste streams or consideration of the efficiency of a building product's digital materiality. The methods of such architectural additive manufacturing must emerge from interdisciplinary research. "Digital Fabrication in Architecture - The Challenge to Transform the Building Industry" Friday, February 17th, 2017 3:00 - 4:30 PM, Room 206 Hynes Convention Center, Boston Additional images and video material available at:


News Article | February 18, 2017
Site: phys.org

In situ Fabricator (construction robot) is fabricating a doubly curved mesh structure during a fabrication test on the Empa NEST building in Duebendorf, Switzerland. Credit: Photo: NCCR Digital Fabrication and ETH Zurich Many building processes still involve sub-standard working conditions and are not compellingly sustainable. Current research on the integration of digital technologies within construction processes promises substantial contributions to sustainability and productivity, while at the same time enabling completely new forms of architectural expression. The multidisciplinary nature of integrating digital processes remains a key challenge to establishing a digital building culture. In order to fully exploit the potential of digital fabrication, an institutional and funding environment that enables strong interdisciplinary research is required. Traditionally separated disciplines such as: architecture, structural design, computer science, materials science, control systems engineering, and robotics now need to form strong research connections. During the AAAS 2017 Annual Meeting in Boston, Jonas Buchli, ETH Zurich - The Swiss Federal Institute of Technology in Zurich, Switzerland, Ronald Rael, University of California, Berkeley, U.S.A., and Jane Burry, RMIT University, Melbourne, Australia reveal the latest developments in digital fabrication in architecture at 1:1 building scale. In their presentations, they show digital technologies can be successfully integrated in design, planning, and building processes in order to successfully transform the building industry. Jonas Buchli, Assistant Professor for Agile and Dexterous Robotics at ETH Zurich in Switzerland and principal investigator in the Swiss National Centre of Competence in Research (NCCR) Digital Fabrication is proposing a radical focus on domain specific robotic technology enabling the use of digital fabrication directly on construction sites and in large scale prefabrication. He demonstrates how researchers at ETH Zurich within the NCCR Digital Fabrication - Switzerland's leading initiative for the development and integration of digital technologies within the field of architecture - are facing the challenge of developing this technology. They bring a comprehensive and interdisciplinary approach that incorporates researchers from architecture, materials science, and robotics. In his presentation, Buchli will provide insight into current research and the future vision and development of the In situ Fabricator, a mobile and versatile construction robot, which in 2017 will be utilized for the first time on an actual building site. The New Mathematics of Making Digital computation has freed designers from the constraints of the static 2- and 3- dimensional representational techniques of drawing and physical modelling. Design attributes can be directly linked to extraneous factors: structural or environmental optimization, or fabrication and material constraints. Mathematical design models contain sufficient information even for computer numerical controlled (CNC) fabrication ma-chines and techniques. Jane Burry, Director of the Spatial Information Architecture Laboratory at RMIT University in Melbourne, Australia, explores how these opportunities for automation, optimization, variation, mass-customization, and quality control can be fully realized in the built environment within full scale construction. Burry shows select digital fabrication examples, where research and innovation have changed construction practice. She will draw on prominent case studies such as the design and construction of Antonio Gaudí's Sagrada Familia. Most materials currently used in 3D printing, were developed to print small scale objects. Ronald Rael, Associate Professor for Architecture at University of California, Berkeley, U.S.A., reveals how he is developing new materials that can overcome the challenges of scale and costs of 3D printing on 1:1 construction scale. He demonstrates that viable solutions for 3D printing in architecture involve a material supply from sustainable resources, culled from waste streams or consideration of the efficiency of a building product's digital materiality. The methods of such architectural additive manufacturing must emerge from interdisciplinary research.


News Article | February 15, 2017
Site: www.eurekalert.org

Global climate change is affecting our planet and mankind; climate science is thus instrumental in informing policy makers about its dangers, and in suggesting emission limits. Science also shows that staying within limits, while meeting the aspirations of a growing global population requires fundamental changes in energy conversion and storage. The majority of low-carbon technology innovation observed in the last decades, such as the 85% cost reduction in photovoltaic cell production since 2000, was driven by largely uncoordinated national policies. These included research incentives in Japan and the U.S., feed-in tariffs in Germany, and tax breaks in the U.S. During the AAAS 2017 Annual Meeting in Boston, Tobias Schmidt, ETH Zurich - The Swiss Federal Institute of Technology in Zurich, Switzerland, Jessika Trancik, Massachusetts Institute of Technology, Cambridge, U.S.A., and Masaru Yarime, City University of Hong Kong, will review the successes and failures of policies for low-carbon technology innovation and show how characteristics of both the technologies and the policy instruments themselves helped and, in some ways, hindered technological progress. In addition, they will demonstrate how research by the innovative science community can inform policy decisions in the future to accelerate low-carbon innovation and affect the livelihood of our planet in the long-term, despite limited resources. Wind and solar energy installations have grown rapidly in recent decades as their costs have fallen. It remains unclear; however, whether these trends will continue, allowing the technologies to measurably contribute to climate change mitigation. Jessika Trancik, Associate Professor of Energy Studies at the Massachusetts Institute of Technology (MIT) in Cambridge, USA, uses the case example of photovoltaic technology to uncover the key determinants of innovation from the formulation of policy to the design of technologies. She explains the feedback of emission reduction and the practical lessons that emerge for engineers and policy makers alike. Recent empirical studies demonstrate that innovation patterns and technological learning can differ strongly between energy technologies. Fostering low-carbon innovation may thus require technology-specific policy interventions. Tobias Schmidt, Assistant Professor of Energy Politics at ETH Zurich, Switzerland compares photovoltaics (PV), wind and lithium-ion battery storage technologies in relation to the locus of innovation in the industry value chain, learning feedback, and type of innovation. He relates his observations to technology architecture and production processes deriving implications for other energy technologies. Based on these analyses, Schmidt makes recommendations for the design of policy portfolios to accelerate innovation in clean energy. Masaru Yarime, Associate Professor at the School of Energy and Environment, City University in Hong Kong presents case studies from Japan and the U.S. on how low-carbon energy technologies can be implemented within the larger systems of smart cities. Their implementation calls for the promotion and integration of a variety of innovations in the electronic, housing, automotive, and infrastructure sectors. This requires collaboration and coordination with relevant stakeholders in academia, industry, government, and civil society. Yarime examines smart city projects with policy implications for platform creation, technological development, and end-user engagement. Meet us at AAAS 2017 "Accelerating Low-Carbon Innovation through Policy" Saturday, February 18th, 2017 8:00 - 9:30 AM Room 311, Hynes Convention Centre Boston, USA


News Article | July 14, 2016
Site: www.realwire.com

Leading international manufacturer of components and systems for optical and electrical connectivity, HUBER+SUHNER, is sponsoring two teams at this year’s Institute of Mechanical Engineers (IME) Formula Student event at Britain’s iconic Silverstone circuit. Formula Student is Europe's most established educational motorsport competition, run by the Institution of Mechanical Engineers and backed by industry and high profile engineers, such as Ross Brawn OBE. The competition aims to inspire and develop enterprising and innovative young engineers. Universities from across the globe are challenged to design and build a single-seat racing car in order to compete in static and dynamic events, which demonstrate their understanding and test the performance of the vehicle. HUBER+SUHNER headquarters is sponsoring the AMZ Racing team based in the Federal Institute of Technology Zurich (ETH Zurich) and also providing cabling for their build. HUBER+SUHNER India has given its backing to the Indian Institute of Technology Bombay Racing team, also supplying cables. “The Formula Student event is a fantastic initiative that champions the great work Engineering students are doing across the world,” said Frank Rothe, who heads the Automotive Market Unit at HUBER+SUHNER. “We’re delighted to have helped two of the teams here today showcase their talents on an iconic stage like Silverstone.” Each participating team is tasked to produce a prototype for a single-seat race car for autocross or sprint racing, and present it to a hypothetical manufacturing firm. The car must be low in cost, easy to maintain, and reliable, with high performance in terms of its acceleration, braking, and handling qualities. During the competition each team must demonstrate the logic behind their proposal and must be able to demonstrate that it can support a viable business model for both parties. “This event is massively valued within the industry, and we are excited to see what the 2016 batch of young engineers has to offer,” concluded Rothe. The Formula Student event runs from 14-17 July, 2016, at Silverstone Circuit, Northamptonshire. Tickets are available from http://formulastudent.imeche.org. To arrange a briefing or product demonstration, please reply to this email or contact the HUBER+SUHNER Team on the details below HUBER+SUHNER Group HUBER+SUHNER is a global company with headquarters in Switzerland that develops and manufactures components and system solutions for electrical and optical connectivity. With cables, connectors and systems – developed from the three core technologies of radio frequency, fiber optics and low frequency – the company serves customers in the communication, transportation and industrial sectors. The products deliver high performance, quality, reliability and long life – even under harsh environment conditions. Our global production network, combined with group companies and agencies in over 60 countries, puts HUBER+SUHNER close to its customers. Further information on the company can be found at hubersuhner.com.


SHENZHEN, China, Oct 31, 2016 /PRNewswire/ -- The first World Medical Robotics Conference, hosted by Medical Robotics Society (MRS) and organized by ROBO Health Institute, was held in Shenzhen on Oct 29th -30th, 2016. The event was chaired by Yangsheng Xu, dean of Chinese University of Hong Kong, Shenzhen. The conference was jointly hosted by Hannes Bleuler, Director of Robotics Laboratory at Federal Institute of Technology in Lausanne, Switzerland and Lining Sun, Director of ROBO Health Institute. Medical robotics are becoming more and more important in the medical industry. The conference focused on scientific research in clinical applications and industrialization of medical robots. Many clinical experts, business leaders, and famous researchers were invited. Other important topics that were discussed during the conference included surgical robots, rehabilitation robots, artificial intelligence, etc. The conference also live broadcasted a surgical operation operated by medical robots. This surgical operation was operated by Dr. Huangjian, the chairman of Chinese Urology Medical Association and Director of Urology in Sun Yat-Sen Memorial Hospital. After the surgery, the speaker and guests visited the National Gene Bank which was opened in September 2016. Official website of the conference: http://www.worldmrs.org/en/events/WMRC2016/ MRS, set up in 2014 and headquartered in Lausanne, Switzerland, is the world's first professional association and non-profit organization devoted to the advancement in medical robotics technology for the improvement of worldwide healthcare conditions.MRS is establishing a main platform for the medical robotics community and its technical professionals for improving worldwide healthcare conditions through the development of robotics and automation technology. For more information, please visit www.worldmrs.org ROBO Health Institute (ROBO), jointly sponsored by ROBO Medical, Lausanne's Robotics Institute of Swiss Federal Institute of Technology (EPFL) and Beijing Genomics Institute(BGI), is a global research institution focusing on medical robotics. ROBO is devoted to the research application of robots and artificial intelligence in medical areas. Our main focus is on surgical robotics, robot-assisted diagnosis, rehabilitation robotics, medial artificial intelligence, health internet of things and big data for medical application, etc. For more information, please visit www.robohi.org To view the original version on PR Newswire, visit:http://www.prnewswire.com/news-releases/the-first-world-medical-robotics-conference-successfully-concludes-in-shenzhen-china-300353931.html


News Article | January 29, 2016
Site: www.cemag.us

An international research team has simplified the steps to create highly efficient silicon solar cells by applying a new mix of materials to a standard design. Arrays of solar cells are used in solar panels to convert sunlight to electricity. The special blend of materials — which could also prove useful in semiconductor components — eliminates the need for a process known as doping that steers the device’s properties by introducing foreign atoms to its electrical contacts. This doping process adds complexity to the device and can degrade its performance. “The solar cell industry is driven by the need to reduce costs and increase performance,” says James Bullock, the lead author of the study, published this week in Nature Energy. Bullock participated in the study as a visiting researcher at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley. “If you look at the architecture of the solar cell we made, it is very simple,” says Bullock, of Australian National University (ANU). “That simplicity can translate to reduced cost.” Other scientists from Berkeley Lab, UC Berkeley, ANU, and The Swiss Federal Institute of Technology of Lausanne (EPFL) also participated in the study. Bullock adds, “Conventional silicon solar cells use a process called impurity doping, which does bring about a number of limitations that are making further progress increasingly difficult.” Most of today’s solar cells use crystalline silicon wafers. The wafer itself, and sometimes the layers deposited on the wafer, are doped with atoms that either have electrons to spare when they bond with silicon atoms, or alternatively generate electron deficiencies, or “holes.” In both cases, this doping enhances electrical conductivity. In these devices, two types of dopant atoms are required at the solar cell’s electrical contacts to regulate how the electrons and holes travel in a solar cell so that sunlight is efficiently converted to electrical current that flows out of the cell. Crystalline silicon-based solar cells with doped contacts can exceed 20 percent efficiency — meaning more than 20 percent of the sun’s energy is converted to electricity. A dopant-free silicon cell had not previously exceeded 14 percent efficiency. The new study, though, demonstrated a dopant-free silicon cell, referred to as a DASH cell (dopant free asymmetric heterocontact), with an average efficiency above 19 percent. This increased efficiency is a product of the new materials and a simple coating process for layers on the top and bottom of the device. Researchers showed it’s possible to create their solar cell in just seven steps. In this study, the research team used a crystalline silicon core (or wafer) and applied layers of dopant-free type of silicon called amorphous silicon. Then, they applied ultrathin coatings of a material called molybdenum oxide, also known as moly oxide, at the sun-facing side of the solar cell, and lithium fluoride at the bottom surface. The two layers, having thicknesses of tens of nanometers, act as dopant-free contacts for holes and electrons, respectively. “Moly oxide and lithium fluoride have properties that make them ideal for dopant-free electrical contacts,” says Ali Javey, program leader of Electronic Materials at Berkeley Lab and a professor of Electrical Engineering and Computer Sciences at UC Berkeley. Both materials are transparent, and they have complementary electronic structures that are well-suited for solar cells. “They were previously explored for other types of devices, but they were not carefully explored by the crystalline silicon solar cell community,” says Javey, the lead senior author of the study. Javey notes that his group had discovered the utility of moly oxide as an efficient hole contact for crystalline silicon solar cells a couple of years ago. “It has a lot of defects, and these defects are critical and important for the arising properties. These are good defects,” he says. Stefaan de Wolf, another author who is team leader for crystalline silicon research at EPFL in Neuchâtel, Switzerland, says, “We have adapted the technology in our solar cell manufacturing platform at EPFL and found out that these moly oxide layers work extremely well when optimized and used in combination with thin amorphous layer of silicon on crystalline wafers. They allow amazing variations of our standard approach.” In the study, the team identified lithium fluoride as a good candidate for electron contacts to crystalline silicon coated with a thin amorphous layer. That layer complements the moly oxide layer for hole contacts. The team used a room-temperature technique called thermal evaporation to deposit the layers of lithium fluoride and moly oxide for the new solar cell. There are many other materials that the research teams hopes to test to see if they can improve the cell’s efficiency. Javey says there is also promise for adapting the material mix used in the solar cell study to improve the performance of semiconductor transistors. “There’s a critical need to reduce the contact resistance in transistors so we’re trying to see if this can help.” Some off the work in this study was performed at The Molecular Foundry, a DOE Office of Science User Facility at Berkeley Lab. This work was supported by the DOE Office of Science, Bay Area Photovoltaics Consortium (BAPVC); the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub; Office fédéral de l’énergie (OFEN); the Australian Renewable Energy Agency (ARENA), and the CSEM PV-center.


News Article | February 15, 2017
Site: phys.org

Adaptive Solar Facade. Credit: Chair for Architecture and Building Systems, Institute of Technology in Architecture, ETH Zurich Global climate change is affecting our planet and mankind; climate science is thus instrumental in informing policy makers about its dangers, and in suggesting emission limits. Science also shows that staying within limits, while meeting the aspirations of a growing global population requires fundamental changes in energy conversion and storage. The majority of low-carbon technology innovation observed in the last decades, such as the 85% cost reduction in photovoltaic cell production since 2000, was driven by largely uncoordinated national policies. These included research incentives in Japan and the U.S., feed-in tariffs in Germany, and tax breaks in the U.S. During the AAAS 2017 Annual Meeting in Boston, Tobias Schmidt, ETH Zurich - The Swiss Federal Institute of Technology in Zurich, Switzerland, Jessika Trancik, Massachusetts Institute of Technology, Cambridge, U.S.A., and Masaru Yarime, City University of Hong Kong, will review the successes and failures of policies for low-carbon technology innovation and show how characteristics of both the technologies and the policy instruments themselves helped and, in some ways, hindered technological progress. In addition, they will demonstrate how research by the innovative science community can inform policy decisions in the future to accelerate low-carbon innovation and affect the livelihood of our planet in the long-term, despite limited resources. Wind and solar energy installations have grown rapidly in recent decades as their costs have fallen. It remains unclear; however, whether these trends will continue, allowing the technologies to measurably contribute to climate change mitigation. Jessika Trancik, Associate Professor of Energy Studies at the Massachusetts Institute of Technology (MIT) in Cambridge, USA, uses the case example of photovoltaic technology to uncover the key determinants of innovation from the formulation of policy to the design of technologies. She explains the feedback of emission reduction and the practical lessons that emerge for engineers and policy makers alike. Considering Different Types of Learning in Low-Carbon Innovation Policy Recent empirical studies demonstrate that innovation patterns and technological learning can differ strongly between energy technologies. Fostering low-carbon innovation may thus require technology-specific policy interventions. Tobias Schmidt, Assistant Professor of Energy Politics at ETH Zurich, Switzerland compares photovoltaics (PV), wind and lithium-ion battery storage technologies in relation to the locus of innovation in the industry value chain, learning feedback, and type of innovation. He relates his observations to technology architecture and production processes deriving implications for other energy technologies. Based on these analyses, Schmidt makes recommendations for the design of policy portfolios to accelerate innovation in clean energy. Masaru Yarime, Associate Professor at the School of Energy and Environment, City University in Hong Kong presents case studies from Japan and the U.S. on how low-carbon energy technologies can be implemented within the larger systems of smart cities. Their implementation calls for the promotion and integration of a variety of innovations in the electronic, housing, automotive, and infrastructure sectors. This requires collaboration and coordination with relevant stakeholders in academia, industry, government, and civil society. Yarime examines smart city projects with policy implications for platform creation, technological development, and end-user engagement. Explore further: Fiscal incentives may help reduce carbon emissions in developing countries


“We are delighted to be awarded ‘very good’ although we are disappointed not to win the title for the eighth time in row,” says Heinz Herren, CIO and CTO Swisscom. “We want to continue to offer our customers the best network and will continue to expand this massively in the future.” In its test report, trade magazine connect states: “The test results clearly show that last year’s winner Swisscom has improved over the past 12 months. Swisscom customers can rest assured that these excellent results mean that this provider would take the number one position in the test field in Germany or Austria immediately.” The results show that infrastructure competition in Switzerland spurs the companies to maximum performance. Swiss customers benefit from mobile phone coverage that is among the best and most advanced in the world. Customers are using their smartphones with increasing intensity and the mobile data volume needed in doubling annually. To meet customer requirements for increased capacity and higher speeds, Swisscom is continually expanding its mobile phone network. Swisscom now covers 99% of the Swiss population with 4G/LTE and around 40% with LTE advanced (with max. speeds of up to 300 Mbit/s). To increase capacity at busy sites, Swisscom has developed antenna solutions in cable ducts. Following successful pilots in the cities of Basel, Bern, Lausanne and Zurich, negotiations to expand the technology are continuing with other towns and communities. Swisscom has invested a total of CHF 1.8 billion in its infrastructure in 2016. Alongside the expansion of the mobile phone network with 4G/LTE, Swisscom is also researching the latest 5G mobile technology standard. In conjunction with Ericsson and research partner Federal Institute of Technology Lausanne (EPFL), Swisscom has established the “5G for Switzerland” programme and is working intensively on the development of the new mobile telephony standard, aiming to launch it on its network in 2020.


News Article | January 27, 2016
Site: phys.org

The special blend of materials—which could also prove useful in semiconductor components—eliminates the need for a process known as doping that steers the device's properties by introducing foreign atoms to its electrical contacts. This doping process adds complexity to the device and can degrade its performance. "The solar cell industry is driven by the need to reduce costs and increase performance," said James Bullock, the lead author of the study, published this week in Nature Energy. Bullock participated in the study as a visiting researcher at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley. "If you look at the architecture of the solar cell we made, it is very simple," said Bullock, of Australian National University (ANU). "That simplicity can translate to reduced cost." Other scientists from Berkeley Lab, UC Berkeley, ANU and The Swiss Federal Institute of Technology of Lausanne (EPFL) also participated in the study. Bullock added, "Conventional silicon solar cells use a process called impurity doping, which does bring about a number of limitations that are making further progress increasingly difficult." Most of today's solar cells use crystalline silicon wafers. The wafer itself, and sometimes the layers deposited on the wafer, are doped with atoms that either have electrons to spare when they bond with silicon atoms, or alternatively generate electron deficiencies, or "holes." In both cases, this doping enhances electrical conductivity. In these devices, two types of dopant atoms are required at the solar cell's electrical contacts to regulate how the electrons and holes travel in a solar cell so that sunlight is efficiently converted to electrical current that flows out of the cell. Crystalline silicon-based solar cells with doped contacts can exceed 20 percent efficiency—meaning more than 20 percent of the sun's energy is converted to electricity. A dopant-free silicon cell had not previously exceeded 14 percent efficiency. The new study, though, demonstrated a dopant-free silicon cell, referred to as a DASH cell (dopant free asymmetric heterocontact), with an average efficiency above 19 percent. This increased efficiency is a product of the new materials and a simple coating process for layers on the top and bottom of the device. Researchers showed it's possible to create their solar cell in just seven steps. In this study, the research team used a crystalline silicon core (or wafer) and applied layers of dopant-free type of silicon called amorphous silicon. Then, they applied ultrathin coatings of a material called molybdenum oxide, also known as moly oxide, at the sun-facing side of the solar cell, and lithium fluoride at the bottom surface. The two layers, having thicknesses of tens of nanometers, act as dopant-free contacts for holes and electrons, respectively. "Moly oxide and lithium fluoride have properties that make them ideal for dopant-free electrical contacts," said Ali Javey, program leader of Electronic Materials at Berkeley Lab and a professor of Electrical Engineering and Computer Sciences at UC Berkeley. Both materials are transparent, and they have complementary electronic structures that are well-suited for solar cells. "They were previously explored for other types of devices, but they were not carefully explored by the crystalline silicon solar cell community," said Javey, the lead senior author of the study. Javey noted that his group had discovered the utility of moly oxide as an efficient hole contact for crystalline silicon solar cells a couple of years ago. "It has a lot of defects, and these defects are critical and important for the arising properties. These are good defects," he said. Stefaan de Wolf, another author who is team leader for crystalline silicon research at EPFL in Neuchâtel, Switzerland, said, "We have adapted the technology in our solar cell manufacturing platform at EPFL and found out that these moly oxide layers work extremely well when optimized and used in combination with thin amorphous layer of silicon on crystalline wafers. They allow amazing variations of our standard approach." In the study, the team identified lithium fluoride as a good candidate for electron contacts to crystalline silicon coated with a thin amorphous layer. That layer complements the moly oxide layer for hole contacts. The team used a room-temperature technique called thermal evaporation to deposit the layers of lithium fluoride and moly oxide for the new solar cell. There are many other materials that the research teams hopes to test to see if they can improve the cell's efficiency. Javey said there is also promise for adapting the material mix used in the solar cell study to improve the performance of semiconductor transistors. "There's a critical need to reduce the contact resistance in transistors so we're trying to see if this can help." Explore further: Cheap, environmentally friendly solar cells are produced by minimizing disruptive surface layers More information: James Bullock et al. Efficient silicon solar cells with dopant-free asymmetric heterocontacts, Nature Energy (2016). DOI: 10.1038/nenergy.2015.31

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