The world’s thinnest LED at only 3 atoms thick:
Researchers at the University of Washington (UW) have demonstrated electroluminescence in a flexible, mechanically strong construct of the semiconductor tungsten selenide only three atoms thick.
The researchers harvested single sheets of tungsten selenide (WSe2) using adhesive tape, a technique invented for the production of graphene. They used a support and dielectric layer of boron nitride on a base of silicon dioxide on silicon, to come up with the thinnest possible LED.
The LEDs now used in most consumer electronics are rigid and are hundreds to thousands of times as thick as the material being developed at UW — which the team characterizes as 1/10,000th the thickness of a human hair.
Existing inorganic LEDs are not appropriate for use in bendable, foldable applications such as electronic devices and displays integrated into clothing. Organic light-emitting diodes are the usual candidates for such applications, but the techniques being pioneered at UW can produce devices that are not only much thinner — and stackable — but also far more versatile.
UW Researchers Create World’s Thinnest LED At Only 3 Atoms Thick - [Link]
Our beloved silicon-based transistors can “only” work at temperatures up to 550° F (around 290° C), which is much more than what’s needed for most general-purpose applications. But those don’t include a nuclear reactor, obviously! (Unless you have one at home. Do you?)
University of Utah engineers have developed tiny plasma-based transistors that can withstand temperatures up to 1,450° F (almost 800° C) and work with ionizing radiation. Since plasma itself is ionized gas, it can even be said that nuclear radiation contributes to proper functioning of these devices. Besides, current plasma-based transistors are about 500-µm long, while these newcomers measure 1–6 µm (!).
[via Elektor Electronics]
March 20, 2014 – University of Utah electrical engineers fabricated the smallest plasma transistors that can withstand high temperatures and ionizing radiation found in a nuclear reactor. Such transistors someday might enable smartphones that take and collect medical X-rays on a battlefield, and devices to measure air quality in real time.
“These plasma-based electronics can be used to control and guide robots to conduct tasks inside the nuclear reactor,” says Massood Tabib-Azar, a professor of electrical and computer engineering. “Microplasma transistors in a circuit can also control nuclear reactors if something goes wrong, and also could work in the event of nuclear attack.”
Tiny Transistors for Extreme Environs - [Link]
Researchers from North Carolina State University have developed a new processing technique that makes light emitting diodes (LEDs) brighter and more resilient by coating the semiconductor material gallium nitride (GaN) with a layer of phosphorus-derived acid.
“By coating polar GaN with a self-assembling layer of phosphonic groups, we were able to increase luminescence without increasing energy input,” says Stewart Wilkins, a Ph.D. student at NC State and lead author of a paper describing the work. “The phosphonic groups also improve stability, making the GaN less likely to degrade in solution.”
New technique makes LEDs brighter, more resilient - [Link]
by Michelle Ma:
Most modern electronics, from flat-screen TVs and smartphones to wearable technologies and computer monitors, use tiny light-emitting diodes, or LEDs. These LEDs are based off of semiconductors that emit light with the movement of electrons. As devices get smaller and faster, there is more demand for such semiconductors that are tinier, stronger and more energy efficient.
University of Washington scientists have built the thinnest-known LED that can be used as a source of light energy in electronics. The LED is based off of two-dimensional, flexible semiconductors, making it possible to stack or use in much smaller and more diverse applications than current technology allows.
Scientists build thinnest-possible LEDs to be stronger, more energy efficient - [Link]
A team of scientists from the University of York, the Helmholtz-Zentrum Berlin (HZB) Germany, and Radboud University Nijmegen, the Netherlands, have developed a new class of magnetic material which flips magnetic state when zapped by an ultra fast laser pulse. This should pave the way to mass storage devices with improved performance and power efficiency compared to current day technology.
The new material demonstrates the use of a synthetic ferrimagnet comprising a sandwich of two ferromagnetic materials and a non-magnetic spacer layer. The spacer layer engineers the coupling between the two ferromagnets so that they align opposite one another. When subjected to an ultrafast laser pulse, this structure spontaneously switches its magnetic state representing writing a single bit of data. [via]
A New Class of Magnetic Material - [Link]
by Rick Robinson:
A research collaboration consisting of IHP-Innovations for High Performance Microelectronics in Germany and the Georgia Institute of Technology has demonstrated the world’s fastest silicon-based device to date. The investigators operated a silicon-germanium (SiGe) transistor at 798 gigahertz (GHz) fMAX, exceeding the previous speed record for silicon-germanium chips by about 200 GHz.
Although these operating speeds were achieved at extremely cold temperatures, the research suggests that record speeds at room temperature aren’t far off, said professor John D. Cressler, who led the research for Georgia Tech. Information about the research was published in February of 2014, by IEEE Electron Device Letters.
Silicon-Germanium Chip Sets New Speed Record - [Link]
Researchers have developed the technology for a catheter-based device that would provide forward-looking, real-time, three-dimensional imaging from inside the heart, coronary arteries and peripheral blood vessels. With its volumetric imaging, the new device could better guide surgeons working in the heart, and potentially allow more of patients’ clogged arteries to be cleared without major surgery.
The device integrates ultrasound transducers with processing electronics on a single 1.4 millimeter silicon chip. On-chip processing of signals allows data from more than a hundred elements on the device to be transmitted using just 13 tiny cables, permitting it to easily travel through circuitous blood vessels. The forward-looking images produced by the device would provide significantly more information than existing cross-sectional ultrasound.
Single Chip Device to Provide Real-Time 3-D Images from Inside the Heart and Blood Vessels - [Link]
Device stores twice the energy of microbatteries currently used in transmitters. By Tom Rickey:
RICHLAND, Wash. – Scientists have created a microbattery that packs twice the energy compared to current microbatteries used to monitor the movements of salmon through rivers in the Pacific Northwest and around the world.
The battery, a cylinder just slightly larger than a long grain of rice, is certainly not the world’s smallest battery, as engineers have created batteries far tinier than the width of a human hair. But those smaller batteries don’t hold enough energy to power acoustic fish tags. The new battery is small enough to be injected into an organism and holds much more energy than similar-sized batteries.
A battery small enough to be injected, energetic enough to track salmon - [Link]