Browse Topic: Semiconductors

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Wearable Health Tech Gets Efficiency UpgradeTBMG-362543/1/2020
North Carolina State University engineers have demonstrated a flexible device that harvests the heat energy from the human body to monitor health. The device surpasses all other flexible harvesters that use body heat as the sole energy source.
Leading Women in Engineering & Science: Dr. Annette Teng, CEO; Lisa Wen, Process EngineerTBMG-362633/1/2020
Hybrid Technique Aims to Produce Stronger, Corrosion-Resistant NickelTBMG-362773/1/2020
Nickel is a widely used metal in the manufacturing industry for both industrial and advanced material processes. Now, Purdue University innovators have created a hybrid technique to fabricate a new form of nickel that may help the future production of life-saving medical devices, as well as hightech devices and vehicles with strong corrosion-resistant protection.
Improved Model Predicts Heat Loss in Gallium Nitride SemiconductorsTBMG-361893/1/2020
Engineers have found that the model currently used to predict heat loss in a common semiconductor material does not apply in all situations. By testing the thermal properties of gallium nitride semiconductors fabricated using four popular methods, they discovered that some techniques produce materials that perform better than others.
Celebrating Women in Engineering & Science: Renee Bernstein, CEO, Cotronics CorporationTBMG-361673/1/2020
Weyl Semimetals (WSM) for Electronics ApplicationsTBMG-360522/1/2020
The major factor determining transport properties of solids is the number of electron states in a vicinity of Fermi level. In equilibrium, no macroscopic flow of electrons exists and, therefore, in order to create such flow, electrons must be excited over their equilibrium distribution. However, electrons with energies well below the Fermi level (compared to the characteristic energy scale kBT, where kB is the Boltzmann constant and T is the temperature), cannot acquire small excitation energy. Indeed, in this case, they would have energy corresponding to already occupied states, which is prohibited by the Pauli principle. In turn, well above the Fermi level, where excitation of electrons is not constrained by the Pauli principle, the electron states are not populated, thus making their contribution to the response negligible.
Multimaterial Fiber “Ink” for 3D-Printed DevicesTBMG-359752/1/2020
A new method uses standard 3D printers to produce functioning devices with the electronics already embedded inside. The devices are made of fibers containing multiple interconnected materials that can light up, sense their surroundings, store energy, or perform other actions.
Q&A: Electrically Conductive Coated Yarn for Wearable, Washable FabricsTBMG-359822/1/2020
Professor Genevieve Dion, Director of Drexel University's (Philadelphia, PA) Center for Functional Fabrics, is collaborating with other experts to coat yarn with the highly conductive, two-dimensional material MXene. They demonstrated that the yarn could be used with standard textile manufacturing techniques to create wearable conductive fabric.
Q&A: A Shape-Morphing, Self-Healing Soft CompositeTBMG-357881/1/2020
Carmel Majidi, Professor of Mechanical Engineering at Carnegie Mellon University, and his team has developed a material with a unique combination of high electrical and thermal conductivity, with actuation and self-repair capabilities that are unlike any other soft composite.
Technique Uses X-Rays to Detect Defective Computer ChipsTBMG-3570912/1/2019
Guaranteeing that computer chips — which can consist of billions of interconnected transistors — are manufactured without defects is a challenge. It’s also a challenge to determine if a chip is compromised. A new technique would allow companies and other organizations to non-destructively scan chips to ensure that they haven’t been altered and that they are manufactured to design specifications without error.
Method Manipulates Electrons and Transmits Information Quantum-MechanicallyTBMG-3571812/1/2019
A quantum computer operates on the principles of quantum mechanics, a unique set of rules that governs at the extremely small scale of atoms and subatomic particles. When dealing with particles at these scales, many of the rules that govern classical physics no longer apply and quantum effects emerge. A quantum computer is able to perform complex calculations, factor extremely large numbers, and simulate the behaviors of atoms and particles at levels that classical computers cannot.
Molecular Engineering for Mechanically Resilient and Stretchable Electronic Polymers and CompositesTBMG-3566412/1/2019
The ability to predict the mechanical properties of organic semiconductors is of critical importance for roll-to-roll production and thermomechanical reliability of organic electronic devices. This research describes the use of coarse-grained molecular dynamics simulations to predict the density, tensile modulus, Poisson ratio, and glass transition temperature for poly(3-hexylthiophene) (P3HT) and its blend with C60. In particular, it is shown that the resolution of the coarse-grained model has a strong effect on the predicted properties.
Molecular Engineering for Mechanically Resilient and Stretchable Electronic Polymers and Composites19AERP12_1012/1/2019
Establishing the design criteria for elasticity and ductility in conjugated polymers and composites by analysis of the structural determinants of the mechanical properties. Air Force Research Laboratory, Arlington, Virginia The ability to predict the mechanical properties of organic semiconductors is of critical importance for roll-to-roll production and thermomechanical reliability of organic electronic devices. This research describes the use of coarse-grained molecular dynamics simulations to predict the density, tensile modulus, Poisson ratio, and glass transition temperature for poly(3-hexylthiophene) (P3HT) and its blend with C60. In particular, it is shown that the resolution of the coarse-grained model has a strong effect on the predicted properties. It was found that a one-site model, in which each 3-hexylthiophene unit is represented by one coarse-grained bead, predicts significantly inaccurate values of density and tensile modulus. In contrast, a three-site model, with one coarse-grained bead for the thiophene ring and two for the hexyl chain, predicts values that are very close to experimental measurements (density = 0.955 g cm−3, tensile modulus = 1.23 GPa, Poisson ratio = 0.35, and glass transition temperature = 290 K). The model also correctly predicts the strain-induced alignment of chain, as well as the vitrification of P3HT by C60 and the corresponding increase in the tensile modulus (tensile modulus = 1.92 GPa, glass transition temperature = 310 K).
Superconductivity in a Nickel Oxide MaterialTBMG-3568912/1/2019
Scientists have made the first nickel oxide material that shows clear signs of superconductivity — the ability to transmit electrical current with no loss. Also known as a nickelate, it's the first unconventional superconductor that is very similar to copper oxides, or cuprates, which indicated that superconductors could someday operate at near-room-temperature and revolutionize electronic devices, power transmission, and other technologies. Those similarities may show that nickelates could also superconduct at relatively high temperatures.
Method Makes Transistors and Electronic Devices from ThreadTBMG-3546711/1/2019
A transistor has been made from linen thread, enabling the creation of electronic devices made entirely of thin threads that could be woven into fabric, worn on the skin, or implanted surgically for diagnostic monitoring. The flexible electronic devices could enable a range of applications that conform to different shapes and allow free movement without compromising function.
Ultrathin Transistors for Faster Computer ChipsTBMG-3528310/1/2019
For decades, microchip transistors have become smaller, faster, and cheaper; however, miniaturization has reached a natural limit, as completely new problems arise when a length scale of only a few nanometers is approached.
Ultra-Clean Fabrication Platform for 2D TransistorsTBMG-351299/1/2019
Recently discovered two-dimensional (2D) materials with superlative properties have the potential to advance semiconductors but creating 2D devices with both good electrical contacts and stable performance has proved challenging.
Organic Semiconductor Thin-Film Sensors Detect Disease Markers in BreathTBMG-348958/1/2019
Organic semiconductors (OSCs) have emerged as a new class of electronic materials promising a wide range of applications including organic field-effect transistors (OFET), solar cells, thermoelectrics, electronic skins, and chemical and mechanical sensors by virtue of their chemical versatility, solution processability, and mechanical flexibility.
Breakthrough Could Enable Infrared Cameras for Electronics, Self-Driving CarsTBMG-347677/1/2019
There's an entire world our eyes miss, hidden in the ranges of light wavelengths that human eyes can't see. But infrared cameras can pick up this light emitted as plants photosynthesize, as cool stars burn, and batteries get hot. They can see through smoke and fog and plastic.
Fabricating Nanochips via Thermal LithographyTBMG-347297/1/2019
A process for fabricating atom-thin processors can be used to produce at the nanoscale for smaller and faster semiconductors.
Laser Diode Based on Organic SemiconductorsTBMG-348017/1/2019
Researchers have demonstrated that a long-elusive kind of laser diode based on organic semiconductors is indeed possible, paving the way for the further expansion of lasers in applications such as biosensing, displays, healthcare, and optical communications.
Direct-Write Quantum Calligraphy in Monolayer SemiconductorsTBMG-346216/1/2019
In contrast with conventional light-emitting diodes (LEDs) that emit billions of photons simultaneously to form a steady stream of light, a single photon emitter (SPE) generates exactly one photon on demand, with each photon indistinguishable from another. These characteristics are essential for photon-based quantum technologies under development. In addition, such capabilities should be realized in a material platform that enables precise, repeatable placement of SPEs in a fully scalable fashion compatible with existing semiconductor chip manufacturing.
Electrical Characterization of Crystalline UO2, THO2 and U0.71TH0.29O2TBMG-345276/1/2019
Tracking and identifying radiation sources in the age of nuclear proliferation and well- resourced non-state actors is a national priority. Current neutron detection methods favor large detector volumes and long data collection times. Additionally, portable neutron detection methods have persistent problems with low signal-to-noise (small pulse height) and require large applied voltages.
Encapsulated Nanoparticles Offer Promise for Biomedical ApplicationsTBMG-344415/1/2019
The Polymerization Process Research Group of the Polymat Institute of the UPV/EHU–University of the Basque Country has efficiently encapsulated semiconductor nanocrystals or quantum dots of various sizes into polymer particles. Great stability in terms of their optical properties and good fluorescence control when combining different quantum dots have been achieved. The possible applicability of these materials as sensors of volatile organic compounds has also been explored.
Electron Beam Heating and Atomic Restructuring of Sapphire SurfacesTBMG-343965/1/2019
NASA’s Langley Research Center has developed a new way to reduce the high-temperature heating requirement of sapphire substrates in wafer production. The growth of high-quality and single-crystal epitaxy layers on sapphires requires uniform and high-temperature heating to accommodate restructuring of the sapphire surface to be aluminum-terminated. These requirements (uniform heating and re-structuring of sapphire substrates) are challenging for high-yield and high-quality production. This innovation offers a new way to reduce the high-temperature heating requirement of sapphire substrates and at the same time create the morphological restructure of sapphire surface required.
Chip Measures Quantities with Quantum PrecisionTBMG-341824/1/2019
Many devices use light to probe the quantum states of atoms in a vapor confined in a small cell. Atoms can be highly sensitive to external conditions, and therefore make superb detectors. Devices based on light interactions with atomic vapors can measure quantities such as time, length, and magnetic fields, and have applications in navigation, communications, medicine, and other fields. Such devices generally must be assembled by hand.
Microfabrication Technique Modifies Semiconductor Material Atom-by-AtomTBMG-339053/1/2019
To keep up with Moore's Law — an observation made in the 1960s that the number of transistors on an integrated circuit doubles about every two years — researchers are finding ways to cram as many transistors as possible onto microchips. The newest trend is 3D transistors that stand vertically, like fins, and measure about 7 nanometers across — tens of thousands of times thinner than a human hair. Tens of billions of these transistors can fit on a single microchip, which is about the size of a fingernail.
High-Power Thermoelectric GeneratorTBMG-339133/1/2019
Objects in our daily lives, such as speakers, refrigerators, and even cars, are becoming “smarter” day by day as they connect to the Internet and exchange data, creating the Internet of Things (IoT). Toward an IoT-based society, a miniaturized thermoelectric generator is anticipated to charge these objects, especially for those that are portable and wearable.
Nanoscale Pillars Act as Memory FoamTBMG-339363/1/2019
A customizable nanomaterial was developed that combines metallic strength with a foam-like ability to compress and spring back. The material can store and release mechanical energy on the nanoscale, and fits into existing industrial semiconductor processes.
Ferrofluid Technology Becomes a Magnet for Pioneering ArtistsTBMG-339413/1/2019
Spinoff is NASA's annual publication featuring successfully commercialized NASA technology. This commercialization has contributed to the development of products and services in the fields of health and medicine, consumer goods, transportation, public safety, computer technology, and environmental resources.
Piezoelectric Resonator with Two LayersTBMG-3320811/1/2018
Microelectromechanical systems (MEMS) filters have advantages in being able to reduce the size, weight, and power required when used as part of electronic systems such as radios; however, MEMS-type filters have limitations. For example, thickness MEMS-type filters (e.g., thickness-extensional mode piezoelectric resonators) are typically limited to a single operating frequency per substrate die. Also, lithographically determined operating frequency resonators cannot meet low-impedance specifications.
Generating Light-Induced Electrical Current in Atomically Thin NanomaterialsTBMG-3310810/1/2018
When hit with light, semiconductors (materials that have an electrical resistance in between that of metals and insulators) generate an electric current. Semiconductors that consist of one layer or a few layers of atoms — for example, graphene, which has a single layer of carbon atoms — are of particular interest for next-generation optoelectronics because of their sensitivity to light, which can controllably alter their electrical conductivity and mechanical flexibility. But the amount of light that atomically thin semiconductors can absorb is limited, thus limiting the materials’ response to light.
“Soft Hardware” Cloth Has Built-In Electronic DevicesTBMG-3311310/1/2018
Optical fibers have been traditionally produced by making a cylindrical object called a preform — essentially, a scaled-up model of the fiber — and then heating it. Softened material is then drawn or pulled downward under tension and the resulting fiber is collected on a spool.
Controlled Manufacture of Porous Silicon CarbideTBMG-328619/1/2018
Extremely fine porous structures with tiny holes — resembling a kind of sponge at the nano level — can be generated in semiconductors. A method was developed for the controlled manufacture of porous silicon carbide (SiC), which has significant advantages over silicon. It possesses greater chemical resistance and can be used for biological applications, for example, without any additional coating required.
Faster, More Efficient Information ProcessingTBMG-328609/1/2018
For decades, computer chips have been shrinking thanks to a steady stream of technological improvements in processing density. Experts have, however, been warning that we'll soon reach the end of the trend known as Moore's Law, in which the number of transistors per square inch on integrated circuits doubles every year. In order to continue improving chip performance, either the material the transistors are made of — from silicon, to carbon nanotubes or graphene — or how current materials store and process information would need to change.
Electrical Contact to Molecules in Semiconductor StructuresTBMG-328309/1/2018
To further develop semiconductor technology, the field of molecular electronics is seeking to manufacture circuit components from individual molecules instead of silicon. Because of their unique electronic properties, molecules are suited to applications that cannot be implemented using conventional silicon technology. This requires reliable and inexpensive methods for creating electrical contacts at the two ends of a molecule.
Material Brings Optical Communication onto Silicon ChipsTBMG-324988/1/2018
An increase in computing performance has been achieved by squeezing ever more transistors into a tighter space on microchips. This downsizing has also meant packing the wiring within microprocessors ever more tightly together, leading to effects such as signal leakage between components, which can slow down communication between different parts of the chip. This delay, known as the “interconnect bottleneck,” is becoming an increasing problem in high-speed computing systems.
Advances in Spintronic DevicesTBMG-325038/1/2018
Spintronic devices promise to solve major problems in today's computers, which use massive amounts of electricity to generate heat. This requires expending even more energy for cooling. By contrast, spintronic devices generate little heat and use relatively minuscule amounts of electricity. Spintronic computers would require no energy to maintain data in memory. They would also start instantly and have the potential to be far more powerful than today's computers.
Fabrication Process Produces Nanostructures for Electronic DevicesTBMG-290316/1/2018
Demands for improved computer processing power have led researchers to explore both new processes and other materials beyond silicon to produce electronic components. Semiconductor devices are created on wafers through a multi-step process to coat, remove, or pattern conductive materials. Traditional processes are wet etch, in which a sample with blocked aspects is immersed in an acid bath to remove substances, and reactive ion etching, in which ions bombard exposed surfaces on the wafer to change its chemical properties and remove materials in those exposed regions. Both have been used to develop the intricate electronic patterns on circuits, and use silicon as a foundation for this type of patterning.
High Performance Motor and Inverter System for a Newly Developed Electric Vehicle2018-01-04614/3/2018
This paper describes a newly developed motor and inverter system with maximum torque of 320 Nm and maximum power of 110 kW for a 2018 model year EV. The system achieves this performance with no increase in size from the previous 2013 model year system with maximum torque of 254 Nm and maximum power of 80 kW. The specific features of the new system described in this paper are summarized below. A new inverter power module that adopts a direct cooling structure produces higher current density than the previous model. The designs of components experiencing structural and electrical variation that affects heat generation by the power semiconductors were confirmed. Furthermore, the motor temperature is estimated for thermal protection. These features allow for control logic that can optimally manage the temperatures of the power semiconductors and the motor to facilitate the high torque performance of the system. The motor voltage management has also been optimized in order to reduce the current level and thereby contributes to the system’s high power performance and high efficiency. The motor also adopts magnets with reduced heavy rare earth elements. This improves heat resistance and obtains resource savings. In addition, one of the novel features of the new EV is e-Pedal that provides not only deceleration but also stopping by operating only the accelerator pedal. This is achieved by motor control logic of the motor and inverter system that generates the optimum motor torque in response to each road grade.
Namiki, Kazushige, Murota, Kohei, Shoji, Mitsuhiro
Process Enables 3D Printing of Nanoscale Metal StructuresTBMG-287004/1/2018
In 3D printing — also known as additive manufacturing — an object is built layer-by-layer, allowing for the creation of structures that would be impossible to manufacture by conventional subtractive methods such as etching or milling.
Ultrathin Semiconductor Materials “Rust” to Insulate CircuitryTBMG-2798212/1/2017
Silicon has several qualities that have led it to become the bedrock of electronics. One is that it features a very good “native” insulator — silicon dioxide, or silicon rust. Exposing silicon to oxygen during manufacturing gives chip makers a way to isolate their circuitry. Other semiconductors do not “rust” into good insulators when exposed to oxygen, so they must be layered with additional insulators — a step that introduces engineering challenges. Two new ultrathin materials share that trait, making them promising materials for electronics of the future.
Flexible, Printable Electronics for Sensor ArraysTBMG-2778911/1/2017
Printable electronics — flexible circuitry that is deposited on some type of plastic substrate — has been a major area of research for decades. But the ability to print the substrate itself greatly increases the range of devices the technique can yield.
High-Resolution, Coherent, Dual-Tip Scanning Probe MicroscopeTBMG-2768910/1/2017
The scanning tunneling microscope (STM) has become one of the most powerful tools used in studying the surface structure of electrically conducting solid-state materials at an atomic resolution. Since its conception, the STM has had the greatest impact in the field of modern surface science because of its superior capability of characterizing and resolving the surface atomic structures and defects. Surface features such as atomic point defects, dislocations, and grain boundary identification can routinely be studied using a STM. Furthermore, STMs also allow the characterization of step structures at the atomic level during the processes of surface preparation and growth of semiconductors, such as epitaxial growth on semiconductor structures.
Products of Tomorrow: July 2017TBMG-272217/1/2017
This column presents technologies that have applications in commercial areas, possibly creating the products of tomorrow. To learn more about each technology, see the contact information provided for that innovation.
Energy Consumption of Passenger Compartment Auxiliary Cooling System Based on Peltier Effect2017-01-01553/28/2017
The closed cabin temperature is anticipated to be cooled down when it is a bit hot inside the driving car. The traditional air-condition lowers the cabin temperature by frequently switching the status of the compressor, which increases the engine’s parasitic power and shortens the compressor’s service-life. The semiconductor auxiliary cooling system with the properties of no moving parts, high control precision and quick response has the potential to assist the on-board air-condition in modulating the cabin temperature with relative small ranges. Little temperature differences between the cabin and the outside environment means that the system energy consumption to ensure the occupant comfort is relatively low and the inefficiency could be made up by the renewable energy source. This research focuses on the influence of the vehicle speed and the ambient temperature over the cooling energy consumption considering occupant heat dissipation in order to maximize the system energy utilization. Firstly, the occupant heat dissipation model is established and the system refrigerating capacity is confirmed for occupant comfort. Secondly, the temperature and the heat flux density at both ends of the semiconductor are studied. Finally, the energy consumption regulations of the auxiliary cooling system are clarified for different vehicle speeds and ambient temperatures. The results show that the vehicle speed is a key factor affecting the supplied current, especially for the vehicle speed less than 40km/h. The system current variation is within 0.4A corresponding to the ambient temperature changes. The occupant heat dissipation changes the current range. The system energy utilization could be improved by controlling the supplied current in a relatively small range at various vehicle speeds and ambient temperatures.
Xu, Yongbing, Tan, Gangfeng, Guo, Xuexun, Ping, Xianyao
Power Module Design Verification for xEV Application Under Extreme Conditions2017-01-12463/28/2017
Power modules play a key role in traction inverters for vehicle electrification applications. The harsh automotive operating environment is a big challenge for power modules. The paper highlights the challenges for power modules usage in electrified vehicles (xEVs), and proposes a design verification procedure for such application in order to ensure the reliable operation under all conditions. First, power modules operate in all climate zones and are exposed to a wide ambient temperature range underhood from -40°C to 105°C. A typical automotive power module should therefore withstand a junction temperature from -40°C to up to 175°C without exceeding its safe operating area (SOA), e.g. avalanche breakdown voltage, maximum current, and thermal limit. Second, an inductive induced high voltage spike could be generated during the power semiconductor fast switching at high voltage and high current conditions. The voltage clamping capability is usually required to prevent power semiconductor breakdown under such high voltage spike. Moreover, IGBT short circuit capability is desired to allow adequate time to trigger protection once a short circuit occurs in the motor windings or the inverter. The power module in xEV application is used as an example to show the proposed design verification process including 1) wide temperature range of operation, 2) voltage clamping capability, and 3) short circuit capability.
Xu, Fan, Chen, Lihua, Yang, Shuitao, Zhou, Yan, Alam, Mohammed Khorshed
Automotive Engineering: March 201717AUTP033/2/2017
Thought leadership at WCX17 Lucid Motors' David Moseley: EV or ICE, "It is all physics" New eye on the road One of the industry's hottest tech suppliers is blazing the autonomy trail by crowd-sourcing safe routes and using AI to learn to negotiate the road. Mobileye's co-founder and CTO explains. Hard, slick and ready to roll A tough, self-renewing catalyst coating developed at Argonne National Laboratory provides unprecedented friction and wear protection for vehicle powertrains, the inventors claim. Sensor ICs, semiconductors and safety To achieve ISO 26262 compliance, engineering practices must be taken to a higher level. The following insights may prove valuable for getting there. New VCR targets 40% BTE Variable-compression ratio with VVA from France's MCE-5. Editorial: Nation of Innovation SAE Standards News Sharpening the focus on OBD-II security Supplier Eye Smaller suppliers facing global challenges Chicago auto show: All-new 2018 Ford Expedition gets aluminum body, 10-speed Chicago fire: Dodge wedges 375-hp Hemi V8 into Durango SRT Visteon tests augmented-reality HUD for Level 4 autonomy Nissan's new King Cab full of patent potential Early ride: Lucid Motors' 1000-hp Air 'alpha' electric prototype Horst Binnig, Rheinmetall CEO, talks e-products
Electron-to-Photon Communication for Quantum ComputingTBMG-265223/1/2017
Princeton University researchers have built a device in which a single electron can pass its quantum information to a particle of light. The particle of light, or photon, then acts as a messenger to carry the information to other electrons, creating connections that form the circuits of a quantum computer.
Glass Fibers with Potential Far Beyond Transmitting LightTBMG-262251/1/2017
Glass fibers do everything from connecting us to the Internet to enabling keyhole surgery by delivering light through an endoscope. But as versatile as today’s fiber optics are, scientists around the world have been working to expand their capabilities by adding semiconductor core materials to the glass fibers.
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