#Biodegradable, flexible silicon transistors Now researchers from the University of Wisconsin-Madison have come up with a new solution to alleviate the environmental burden of discarded electronics.
This work opens the door for green, low-cost, portable electronic devices in future. Array"We found that cellulose nanofibrillated fiber based transistors exhibit superior performance as that of conventional silicon-based transistors,
"said Zhenqiang Ma, the team leader and a professor of electrical and computer engineering at the UW-Madison."
"And the bio-based transistors are so safe that you can put them in the forest,
"Nowadays, the majority of portable electronics are built on nonrenewable, non-biodegradable materials such as silicon wafers,
All these superior properties make cellulose nanofibril an outstanding candidate for making portable green electronics.
Ma's team employed silicon nanomembranes as the active material in the transistor--pieces of ultra-thin films (thinner than a human hair) peeled from the bulk crystal
and glued onto the cellulose nanofibrill substrate to create a flexible, biodegradable and transparent silicon transistor.
But to make portable electronics, the biodegradable transistor needed to be able to operate at microwave frequencies,
which is the working range of most wireless devices. The researchers thus conducted a series of experiments such as measuring the current-voltage characteristics to study the device's functional performance,
which finally showed the biodegradable transistor has superior microwave-frequency operation capabilities comparable to existing semiconductor transistors."
"Biodegradable electronics provide a new solution for environmental problems brought by consumers'pursuit of quickly upgraded portable devices,
"It can be anticipated that future electronic chips and portable devices will be much greener and cheaper than that of today."
"Next, Ma and colleagues plan to develop more complicated circuit system based on the biodegradable transistors s
when they are separated from one another on a chip. This research could contribute to the creation of futuristic quantum networks operating using quantum teleportation,
which could allow information contained in quantum bits-qubits-to be shared between many elements on chip,
"The quantum dots, each around 100 nanometers in size, were grown at random positions on a semiconductor chip.
This chip was examined painstakingly using an atomic force microscope to discover pairs of dots that were close enough that they might function properly."
albeit more complex, device to prepare entangled electron pairs to teleport qubit states across a chip."
#Faster detection of hidden objects by terahertz sensor Called'Q-Eye',the invention senses radiation across the spectrum between microwaves and infrared, known as the Terahertz (THZ) region of the spectrum
when electromagnetic radiation emitted by an object is absorbed by the Q-Eye sensor, even down to the level of very small packets of quantum energy (a single photon).
and detection performance and our initial calculations indicated world-beating detector capability--all this and using silicon."
large numbers of detector chips containing designs matched to a particular application can easily be fabricated on large (300mm) wafers with great uniformity,
This revolutionary e-cooling process is the secret to Q-Eye sensor's exceptional performance
physicists have used graphene to build lightweight ultrasonic loudspeakers and microphones, enabling people to mimic bats
"Until now, we have not had good wideband ultrasound transmitters or receivers. These new devices are a technology opportunity."
"Speakers and microphones both use diaphragms, typically made of paper or plastic, that vibrate to produce
The grapheme loudspeakers and microphones operate from well below 20 hertz to over 500 kilohertz.
"There's a lot of talk about using graphene in electronics and small nanoscale devices, but they're all a ways away,
and Berkeley Lab."The microphone and loudspeaker are some of the closest devices to commercial viability,
and since then has been developing the electronic circuitry to build a microphone with a similar graphene diaphragm.
One big advantage of graphene is that the atom-thick sheet is so lightweight that it responds well to the different frequencies of an electronic pulse, unlike today's piezoelectric microphones and speakers.
when using ultrasonic transmitters and receivers to transmit large amounts of information through many different frequency channels simultaneously,
or to measure distance, as in sonar applications.""Because our membrane is so light, it has an extremely wide frequency response
whereas today's conventional loudspeakers and headphones convert only 8 percent into sound. Zettl anticipates that in the future,
Arraywhen Zhou told his wife, Jinglin Zheng, about the ultrasound microphone, she suggested he try to capture the sound of bats chirping at frequencies too high for humans to hear.
So they hauled the microphone to a park in Livermore and turned it on. When they slowed down the recording to one-tenth normal speed,
,"These new microphones will be incredibly valuable for studying auditory signals at high frequencies, such as the ones used by bats.
"Zettl noted that audiophiles would also appreciate the graphene loudspeakers and headphones, which have a flat response across the entire audible frequency range."
which is a transmitter. A group of researchers at KAIST has developed a wireless-power transfer (WPT) technology that allows mobile devices to be charged at any location and in any direction,
flat transmitter (Tx) system shaped in a rectangle with a size of 1m2. Either 30 smartphones with a power capacity of one watt each or 5 laptops with 2. 4 watts each can be simultaneously
and wirelessly charged at a 50 cm distance from the transmitter with six degrees of freedom, regardless of the devices'three-axes positions and directions.
This means that the device can receive power all around the transmitter in three-dimensional space.
and connected with a resonant capacitor. Comparing to a conventional loop coil, the dipole coil is very compact
because the devices still require close contact with the transmitter, a charging pad. To use the devices freely
"Our transmitter system is safe for humans and compatible with other electronic devices. We have solved three major issues of short charging distance,
"Array"This opens up a new opportunity for building electronics for enhanced sensing and stimulation at bio-interfaces,"said lead author Zhiqiang Luo, a postdoctoral scholar in Tian's laboratory.
The team achieved three advances in the development of semiconductor and biological materials. One advance was the demonstration, by strictly chemical means, of three-dimensional lithography.
"The idea of utilizing deposition-diffusion cycles can be applied to synthesizing more complex 3d semiconductors,
Arraythe semiconductor industry uses wet chemical etching with an etch-resist to create planar patterns on silicon wafers.
This method also applies to the 3d lithography of many other semiconductor compounds.""This is a fundamentally new mechanism for etch mask
"One of the major hurdles in the area of bioelectronics or implants is that the interface between the electronic device
WATCH requires no coordination with or changes to legacy TV transmitters. Instead TV signals are broadcast as normal
Discovery of single-crystal silicon--the semiconductor in every integrated circuit--made the electronics revolution possible.
Semiconductors like silicon don't self-assemble into perfectly ordered structures like polymers Do it's almost unheard of to get a 3-D structured single crystal of a semiconductor.
"Having the ability to mold the workhorse of all electronics, silicon, into intricate shapes is unprecedented,
#Potential of blue LEDS as novel chemical-free food preservation technology A team of scientists from the National University of Singapore (NUS) has found that blue light emitting diodes (LEDS) have strong antibacterial
when in cold temperatures (between 4°C and 15°C) and mildly acidic conditions of around ph 4. 5. This opens up novel possibilities of using blue LEDS as a chemical-free food preservation method.
Acidic foods such as fresh-cut fruits and ready-to-eat meat can be preserved under blue LEDS in combination with chilling temperatures without requiring further chemical treatments that are needed commonly for food preservation.
These findings were published recently in the Food microbiology journal in June 2015 Enhancing blue LEDS'ability to deactivate bacteria
While LEDS are most commonly known as an energy saving light source, they have also been known to have an antibacterial effect.
Exposure to illumination from blue LED light can hence start off a process within the cells that ultimately causes the cells to die.
can affect the antibacterial effect of LEDS. In this study, the team placed three major foodborne pathogens--Listeria monocytogenes, Escherichia coli o157:
A previous study in 2013 by the same team had looked also at the effect of temperature on blue LED's ability to deactivate bacterial cells
"The next step for us is to apply this LED TECHNOLOGY to real food samples such as fresh-cut fruits,
#Noninvasive device could end daily finger pricking for people with diabetes A new laser sensor that monitors blood glucose levels without penetrating the skin could transform the lives of millions of people living with diabetes.
which use implanted sensors that need regular replacement. Professor Jose said:""Unlike the traditional method, this new noninvasive technology can constantly monitor blood glucose levels."
"The glass used in our sensors is hardwearing, acting in a similar way as that used in smartphones.
Unlike graphene, phosphorene is a semiconductor, like silicon, which is the basis of current electronics technology."
"Because phosphorene is so thin and light, it creates possibilities for making lots of interesting devices,
such as LEDS or solar cells,"said lead researcher Dr Yuerui (Larry) Lu, from The Australian National University (ANU)."
"The team created phosphorene by repeatedly using sticky tape to peel thinner and thinner layers of crystals from the black crystalline form of phosphorus. As well as creating much thinner and lighter semiconductors than silicon,
Array"By changing the number of layers we can tightly control the band gap, which determines the material's properties,
such as the colour of LED it would make.""You can see quite clearly under the microscope the different colours of the sample,
This led to their discovery of the graphene nanoscrolls, which helped to fill in the blanks.
#Transparent, electrically conductive network of encapsulated silver nanowires The electrodes for connections on the"sunny side"of a solar cell need to be not just electrically conductive,
but transparent As well as a result, electrodes are made currently either by using thin strips of silver in the form of a coarse-meshed grid squeegeed onto a surface,
and entirely devoid of indium to produce a technologically intriguing electrode. The doctoral student initially made a suspension of silver nanowires in ethanol using wet-chemistry techniques.
Encapsulation by AZO crystals Subsequently, Göbelt used an atomic layer deposition technique to gradually apply a coating of a highly doped wide bandgap semiconductor known as AZO.
Quality map calculated Measurements of the electrical conductivity showed that the newly developed composite electrode is comparable to a conventional silver grid electrode.
they could evaluate images taken with a scanning electron microscope and predict the electrical conductivity of the electrodes from them."
"We are investigating where a given continuous conductive path of nanowires is interrupted to see where the network is not yet optimum,
Even with high-performance computers, it still initially took nearly five days to calculate a good"quality map"of the electrode.
"The image analysis has given us valuable clues about where we need to concentrate our efforts to increase the performance of the electrode,
Practical aternative to conventional electrodes"We have developed a practical, cost-effective alternative to conventional screen-printed grid electrodes and to the common ITO type that is threatened
however by material bottlenecks,"says Christiansen, who heads the Institute of Nanoarchitectures for Energy conversion at HZB
Only a fraction of silver, nearly no shadow effects The new electrodes can actually be made using only 0. 3 grams of silver per square metre,
while conventional silver grid electrodes require closer to between 15 and 20 grams of silver.
In addition, the new electrode casts a considerably smaller shadow on the solar cell.""The network of silver nanowires is so fine that almost no light for solar energy conversion is lost in the cell due to the shadow,
Using light-emitting diodes, or LEDS, the UC Berkeley researchers were able to heat electrons at the interface of thin films of gold and a DNA solution.
They clocked the speed of heating the solution at around 55 degrees Fahrenheit per second.
The gold was deposited onto a plastic chip with microfluidic wells to hold the PCR mixture with the DNA sample.
The light source was an array of off-the-shelf LEDS positioned beneath the PCR wells. The peak wavelength of the blue LED light was tuned 450 nanometers
who is also co-director of the Berkeley Sensor and Actuator Center.""It can be integrated into an ultrafast genomic diagnostic chip,
which we are developing for practical use in the field. Because this technology yields point-of-care results, we can use this in a wide range of settings, from rural Africa to a hospital ER
silky mesh studded with tiny electronic devices, and shown that it unfurls to spy on and stimulate individual neurons.
So far, even the best technologies have been composed of relatively rigid electronics that act like sandpaper on delicate neurons.
The Harvard team solved these problems by using a mesh of conductive polymer threads with either nanoscale electrodes
or transistors attached at their intersections. Each strand is as soft as silk and as flexible as brain tissue itself.
The next steps will be to implant larger meshes containing hundreds of devices, with different kinds of sensors,
who has developed a gelatin-based eedlefor delivering electrodes to the brain. But he remains sceptical of this technique:
a team of Harvard researchers describe the creation of a flexible nanowire mesh with nanoscale electrodes
or transistors placed at each wired junction. The mesh is malleable,"soft as silk, "and spacious, allowing it to naturally incorporate into the brain
Lieber says. ut with our injectable electronics, it as if it not there at all. They are one million times more flexible than any state-of-the-art flexible electronics
and have sub-cellular feature sizes. Theye what I call euro-philic? they actually like to interact with neurons.
and scale it up to include hundreds of elements and multiple types of sensors. One such sensor, for example, might be a airpin-shapednanowire able to measure electrical activity both inside and outside neurons.
It should be noted, of course, that the research is still in the early stages. Just because it works in mice doesn mean it will perform identically in humans.
#New Spaceship Antenna Prevents Radio Silence During Fiery Re-Entry When future spacecraft re-enter the atmosphere,
a new kind of antenna might help them keep in contact with ground control, despite the fiery sheaths of superhot plasma around them, researchers say.
Now, Gao and his colleague Binhao Jiang, also of the Harbin Institute of technology, reveal they might be able to use the plasma sheath itself to enhance signals from antennas to maintain communications during hypersonic flight."
The researchers suggested adding a carefully designed layer of electrically insulating material onto communications antennas that would essentially store electrical energy.
Sony entered the budding space with the announcement of its Project Morpheus headset in March last year.
Facebook chairman Mark Zuckerberg allegedly tested out Sony VR hardware, designed for its Playstation 4 console,
The eye-tracking cameras are combined with an accelerometer for orientation sensing and head tracking, which allows a user to move their head to manipulate the 360-degree view while still controlling virtual interactions with their eyes.
At last March Game Developer Conference in San francisco, Sony US-based Magic Lab research and development team showed off an external infrared camera that enables players to scan the environment using their eyes
Razer CEO, speaking at the recent Consumer electronics Show (CES) in Las vegas, said that he hopes the headset will speed the development of the virtual reality platform by allowing developers to hack it as they please.
She spent four years at Sony Computer Entertainment and then became a social gaming director at Japanese mobile gaming firm GREE,
Kojima tells Tech in Asia. here are huge companies making complicated electronics, and wee close to manufacturing centers in China,
so I want to do the same with a more complex, emotional experience. efore Sony, I thought games were just for children,
#Researchers Power Small Electronics Using Wi-fi: Clarkson Waves Your Wi-fi router already brings you Netflix and cat pictures,
A group of researchers from the University of Washington were able to send energy from a Wi-fi router to low power electronics from up to 28 feet away,
a temperature sensor, a camera, a coin battery charger and the AA battery charger shown above.
In their tests, they were able to operate the camera up to 17 feet away, the temperature sensor up to 20ft away and the battery chargers up to 28 feet away from their router.
Using a 2. 4ghz antenna and their harvester the researchers also built a wireless USB charger (top image.
They also installed harvester-equipped temperature sensors 10 feet away from each router. Their results showed that the routers performed well,
and from neighboring routers while still sending enough power to the temperature sensors. The researchers hope that their technology will lead to battery-free sensors
and mobile devices that are powered continuously by Wi-fi routers. Check out the researcher full paper at Cornell University Library arxiv. via New Scientist via Digital Trends
Beyond Gaming Kojima already has had storied a career heading up development of several Sony games--for the PSP, Playstation 3, Playstation Vita and Playstation Move.
#IBM-Led Team Pulls Off Major Chip Feat IBM Research on Thursday announced that an alliance it leads has produced the first 7nm node test chips with functioning transistors.
Big Blue's partners are Globalfoundries, Samsung and the State university of New york Polytechnic institute's Colleges of Nanoscale Science and Engineering (SUNY Poly CNSE.
The alliance sought to develop industry-first innovations, such as Silicon Germanium (Sige) channel transistors, and Extreme Ultraviolet (EUV) lithography integration at multiple levels.
The 7nm chips are the result of the first program out of IBM's 2014 US$3 billion investment in research--a five-year investment that aims to push the limits of chip technology to meet the needs of cloud computing
Using 7nm chips will allow the placement of more than 20 billion Sige switches on fingernail-sized chips,
said Mukesh Khare, vice president of IBM Semiconductor Technology Research.""We intend to incorporate 7nm into the road maps for IBM systems in the future,
--and it's getting increasingly expensive to make faster chips. That has led semiconductor firms to look at packing more cores onto their processors.
The number of transistors in an integrated circuit doubles roughly every two years, according to Moore's Law,
but the semiconductor industry for some years has been concerned that it is fast reaching the upper limit of just how many transistors can be packed into an IC.
Size--or the lack of it--has become crucial. Intel apparently expects to be able to build 5nm transistors at some point."
"The higher the density of transistors, the more cores you can put in a given space,"noted Rob Enderle, principal analyst at the Enderle Group."
"A very high-density part would be ideal for the cloud, which is why ARM
Challenges IBM Will Face The IBM alliance has to ensure that it develops technology that will let it manufacture Sige transistor channels in high volumes,
control electronics, cameras and haptics (force-feedback controllers. The control software evolved directly from the Dextre
#Biometric information sensor that directly adheres to the body like a plaster Professor Takao Someya postdoctoral researcher Sung Won Lee
and succeeded in manufacturing a sheet sensor that can measure biometric information just by application to the body like a sticking plaster.
To improve the accuracy of measurements it is ideal to put the sensor in direct contact with
when sensors are applied directly to the body researchers are seeking to fabricate electronic components on flexible substances such as polymeric film.
Furthermore they used the gel to realize sheet sensors that can perform biometric measurement just by application to the body like a sticking plaster.
These sheet sensors can detect bioelectric signals such as physical movement or electrical activity of the heart by directly applying to human skin or the surface of the heart of a rat.
The adhesive gel prevents the sheet sensor from slipping or falling off the surface during dynamic movement and allows stable and long-term measurement t
as well as studying how to expand this technique to other materials such as semiconductors or dielectrics, opening up the possibility of water repellent electronics.
#New laser could upgrade the images in tomorrow#s technology A new semiconductor laser developed at Yale has the potential to significantly improve the imaging quality of the next generation of high-tech microscopes laser projectors photo
Based on a chaotic cavity laser the technology combines the brightness of traditional lasers with the lower image corruption of light emitting diodes (LEDS.
The problem is LEDS are not bright enough for high-speed imaging. The new electrically pumped semiconductor laser offers a different approach.
It produces an intense emission but with low spatial coherence. or full-field imaging the speckle contrast should be less than 4%to avoid any disturbance for human inspectionexplained Hui Cao professor of applied physics
Lee and Huang grew the laser semiconductor wafer via molecular beam epitaxy and helped in fabrication and testing.
#Tattoo-like sensor can detect glucose levels without a painful finger prick Scientists have developed the first ultra-thin flexible device that sticks to skin like a rub-on tattoo
The sensor reported in a proof-of-concept study in the ACS journal Analytical Chemistry has the potential to eliminate finger-pricking for many people with diabetes.
Sunlight to electricity Solar cells work by converting photons of sunlight into an electric current that moves between two electrodes.
A key roadblock to building an efficient perovskite-silicon tandem has been a lack of transparency. olin had to figure out how to put a transparent electrode on the top
Mcgehee said. o one had made ever a perovskite solar cell with two transparent electrodes. Perovskites are damaged easily by heat and readily dissolve in water.
This inherent instability ruled out virtually all of the conventional techniques for applying electrodes onto the perovoskite solar cell
#Laser-induced graphene#super#for electronics Rice university scientists advanced their recent development of laser-induced graphene (LIG) by producing
and testing stacked, three-dimensional supercapacitors, energy storage devices that are important for portable, flexible electronics. The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick
lattice of carbon. The researchers viewed the porous, conductive material as a perfect electrode for supercapacitors or electronic circuits.
To prove it, members of the Tour group have extended since their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet.
The sections are stacked then with solid electrolytes in between for a multilayer sandwich with multiple microsupercapacitors.
Capacitors use an electrostatic charge to store energy they can release quickly, to a camera flash, for example.
Unlike chemical-based rechargeable batteries, capacitors charge fast and release all their energy at once when triggered.
Supercapacitors combine useful qualities of both the fast charge/discharge of capacitors and high-energy capacity of batteries into one package.
LIG supercapacitors appear able to do all that with the added benefits of flexibility and scalability.
-and-release characteristics of a supercapacitor. In testing, the researchers charged and discharged the devices for thousands of cycles with almost no loss of capacitance.
To show how well their supercapacitors scale up for applications, the researchers wired pairs of each variety of device in serial and parallel.
The vertical supercapacitors showed almost no change in electrical performance when flexed, even after 8, 000 bending cycles.
LIG supercapacitors of the same size offer three times the performance in power (the speed at which energy flows).
And the LIG devices can easily scale up for increased capacity. ee demonstrated that these are going to be excellent components of the flexible electronics that will soon be embedded in clothing and consumer goods,
#Carbon nanotube finding could lead to flexible electronics with longer battery life University of Wisconsin-Madison materials engineers have made a significant leap toward creating higher-performance electronics with improved battery life and the ability to flex
In addition to paving the way for improved consumer electronics, this technology could also have specific uses in industrial and military applications.
Gopalan and their students reported transistors with an on-off ratio that 1, 000 times better and a conductance that 100 times better than previous state-of-the-art carbon nanotube transistors. arbon nanotubes are very strong and very flexible,
so they could also be used to make flexible displays and electronics that can stretch and bend, allowing you to integrate electronics into new places like clothing,
says Arnold. he advance enables new types of electronics that aren possible with the more brittle materials manufacturers are currently using.
Carbon nanotubes are single atomic sheets of carbon rolled up into a tube. As some of the best electrical conductors ever discovered
carbon nanotubes have long been recognized as a promising material for next-generation transistors, which are semiconductor devices that can act like an on-off switch for current
This forms the foundation of an electronic device. However, researchers have struggled to isolate purely semiconducting carbon nanotubes,
The team most recent advance also brings the field closer to realizing carbon nanotube transistors as a feasible replacement for silicon transistors in computer chips and in high-frequency communication devices,
and performance limits. he advance enables new types of electronics that aren possible with the more brittle materials manufacturers are currently using.
Our carbon nanotube transistors are an order of magnitude better in conductance than the best thin film transistor technologies currently being used commercially
while still switching on and off like a transistor is supposed to function. The researchers have patented their technology through the Wisconsin Alumni Research Foundation
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