At the IEEE Photovoltaic Specialists Conference in Tampa, Fla. last week, National Renewable Energy Laboratory scientist Myles Steiner announced a world record of 31.1% conversion efficiency for a two-junction solar cell under one sun of illumination. The achievement edges the previous record of 30.8% by Alta Devices.
Silicon can accept ten times more lithium than the graphite used in the electrodes in lithium-ion batteries, but silicon also expands, shortening electrode life. Looking for an alternative to pure silicon, scientists in Germany have now synthesized a novel framework structure consisting of boron and silicon, which could serve as electrode material.
Researchers in Munich, Germany, have recently published work that describes experiments in which inexpensive semiconductor lasers have produced high-energy light pulses as short as 60 picoseconds without the drawbacks of previous approaches in terms of power consumption and device size. They say the new technique, based on the use of a new Fourier domain mode-locked laser, could open the door to subpicosecond pulses.
High-performance thermoelectric materials that convert waste heat to electricity could one day be a source of more sustainable power. But they need to be a lot more efficient before they could be effective on a broad scale in places like power plants or military bases, researchers say. A University of Michigan researcher has taken a step toward that goal.
Leaders of the National Science Foundation (NSF) and the Semiconductor Research Corporation (SRC), the world's leading university-research consortium for semiconductors and related technologies, this week announced 18 new projects funded through a joint initiative to address research challenges in the design of failure-resistant circuits and systems.
Researchers at North Carolina State University have developed a new technique for creating high-quality semiconductor thin films at the atomic scale—meaning the films are only one atom thick. The technique can be used to create these thin films on a large scale, sufficient to coat wafers that are two inches wide, or larger.
From the high-resolution glow of flat screen televisions to light bulbs that last for years, light-emitting diodes (LEDs) continue to transform technology. Their full potential, however, remains untapped. A contentious controversy surrounds the high intensity of indium gallium nitride, with experts split on whether or not indium-rich clusters within the material provide the LED's remarkable efficiency.
From powerful computers to super-sensitive medical and environmental detectors that are faster, smaller, and use less energy—yes, we want them, but how do we get them? In research that is helping to lay the groundwork for the electronics of the future, University of Delaware scientists have confirmed the presence of a magnetic field generated by electrons which scientists had theorized existed, but that had never been proven until now.
University of Utah metallurgists have used an old microwave oven to produce a nanocrystal semiconductor rapidly using cheap, abundant, and less toxic metals than other semiconductors. X-ray crystallography, electron microscopy, and atomic spectroscopy all helped confirm that the CZTS (copper, zinc, tin, and sulfur) semiconductor was suitable for use in a solar cell.
Thermoelectric materials can be used to turn waste heat into electricity or to provide refrigeration without any liquid coolants, and a research team from the University of Michigan has found a way to nearly double the efficiency of a particular class of them that's made with organic semiconductors.
An international team of researchers has recently succeeded in both initializing and reading nuclear spins—which are relevant to qubits for quantum computers—at room temperature. With the help of a spin filter developed in 2009, the team has produced a flow of free electrons with a given spin in a material.
Wake Forest University's Organic Electronics group has developed an organic semiconductor “spray paint” that can be applied to large surface areas without losing electric conductivity. The new spray-deposition method has the advantages of drop casting, spin coating, and prior spray-on techniques: It can applied to large surfaces of any medium, retaining electrical performance.
A team of electrical engineers from Columbia University has generated a record amount of power output—by a power of five—using silicon-based nanoscale CMOS technology for millimeter-wave power amplifiers. Power amplifiers are used in communications and sensor systems to boost power levels for reliable transmission of signals over long distances as required by the given application.
Unlike the building blocks of conventional hard disk drives and memories, resistive memory cells (ReRAM) are active electrochemical components. In these cells, ions generate voltage on electrodes in a similar manner to a battery. Researchers in Europe have conducted an extensive study of ReRAMs, also described as memristors, and have found previously undiscovered sources of voltage in these devices.
When a team of University of Illinois engineers set out to grow nanowires of a compound semiconductor on top of a sheet of graphene, they did not expect to discover a new paradigm of epitaxy. The self-assembled wires have a core of one composition and an outer layer of another, a desired trait for many advanced electronics applications.
By introducing high tensile strain, a research group in Switzerland has rendered germanium, which is normally unsuitable for lasers, capable of emitting 25 times more photons than in its relaxed state. This change alters the optical properties of the material and is enough to allow the construction of lasers from this material. This is valuable because germanium is highly compatible with silicon.
A local power failure in Ohio ten years ago caused a series of cascading power failures that resulted in a massive blackout. Such blackouts could be prevented in the future, thanks to a new piece of equipment developed by engineering researchers at the University of Arkansas. The device regulates or limits the amount of excess current that moves through the power grid when a surge occurs.
Researchers are developing a new type of semiconductor technology for future computers and electronics based on "2D nanocrystals" layered in sheets less than a nanometer thick that could replace today's transistors. The layered structure is made of a material called molybdenum disulfide, which belongs to a new class of semiconductors—metal di-chalogenides—emerging as potential candidates to replace today's CMOS technology.
The same material that formed the first primitive transistors more than 60 years ago can be modified in a new way to advance future electronics, according to a new study. Chemists at The Ohio State University have developed the technology for making a one-atom-thick sheet of germanium, and found that it conducts electrons more than ten times faster than silicon and five times faster than conventional germanium.
In a development that could make the advanced form of secure communications known as quantum cryptography more practical, University of Michigan researchers have demonstrated a simpler, more efficient single-photon emitter that can be made using traditional semiconductor processing techniques.
To increase the neutron detection efficiency of bulk-micromegas (MICRO-MEsh GAseous Structure) neutron detectors, researchers from China and the University of Tennessee-Knoxville have proposed three new types of thin-film converters: micro-channel, parallel micro-pillar, and oblique micro-pillar 2D array. When validated using Monte Carlo simulations, the latter design showed a threefold increase in neutron detection efficiencies.
Certain semiconductors, when imparted with energy, in turn emit light; they directly produce photons, instead of producing heat. This phenomenon is commonplace and used in light-emitting diodes, or LEDs. Research from the University of Pennsylvania has enabled "bulk" silicon to emit broad-spectrum, visible light for the first time, opening the possibility of using the element in devices that have both electronic and photonic components.
Researchers sponsored by Semiconductor Research Corporation (SRC) have developed a modeling process designed to simulate atomic-level etching with chemicals that are effective alternatives to widely used perfluorocarbon (PFC) gases. The novel approach will identify and evaluate green plasma chemistries for processing emerging memory/logic devices and through-silicon-via (TSV)-enabled technologies for the semiconductor industry.
Semiconducting polymers are an unruly bunch, but University of Michigan engineers have developed a new method for getting them in line that could pave the way for cheaper, greener, "paint-on" plastic electronics.
MEH-PPV is a low-cost polymer that can be integrated with silicon chips, and researchers have sought to use it to convert electricity into laser light for use in photonic devices. However, attempts to do this have failed because the amount of electricity needed to generate laser light in MEH-PPV was so high that it caused the material to degrade. Researchers have recently come up with a low-cost way to enhance MEH-PPV’s ability to confine light, protecting the material.