Electronics news and discussion thread

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Engineers 3D print the electromagnets at the heart of many electronics
https://techxplore.com/news/2024-02-3d- ... onics.html
by Adam Zewe, Massachusetts Institute of Technology

Imagine being able to build an entire dialysis machine using nothing more than a 3D printer.

This could not only reduce costs and eliminate manufacturing waste, but since this machine could be produced outside a factory, people with limited resources or those who live in remote areas may be able to access this medical device more easily.

While multiple hurdles must be overcome to develop electronic devices that are entirely 3D printed, a team at MIT has taken an important step in this direction by demonstrating fully 3D-printed, three-dimensional solenoids.

Solenoids, electromagnets formed by a coil of wire wrapped around a magnetic core, are a fundamental building block of many electronics, from dialysis machines and respirators to washing machines and dishwashers.

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Mixed-dimensional transistors enable high-performance multifunctional electronic devices
https://techxplore.com/news/2024-02-dim ... ional.html
by City University of Hong Kong

The downscaling of electronic devices, such as transistors, has reached a plateau, posing challenges for semiconductor fabrication. However, a research team led by materials scientists from City University of Hong Kong (CityU) recently discovered a new strategy for developing highly versatile electronics with outstanding performance using transistors made of mixed-dimensional nanowires and nanoflakes.

This innovation paves the way for simplified chip circuit design, offering versatility and low power dissipation in future electronics. The findings, titled "Multifunctional anti-ambipolar electronics enabled by mixed-dimensional 1D GaAsSb/2D MoS2 heterotransistors," were published in the journal Device.

In recent decades, as the continuous scaling of transistors and integrated circuits has started to reach physical and economic limits, fabricating semiconductor devices in a controllable and cost-effective manner has become challenging. Further scaling of transistor size increases current leakage and thus power dissipation. Complex wiring networks also have an adverse impact on power consumption.

Multivalued logic (MVL) has emerged as a promising technology for overcoming increasing power consumption. It transcends the limitations of conventional binary logic systems by greatly reducing the number of transistor components and their interconnections, enabling higher information density and lower power dissipation. Significant efforts have been devoted to constructing various multivalued logic devices, including anti-ambipolar transistors (AAT).

Anti-ambipolar devices are a class of transistors in which positive (holes) and negative (electron) charge carriers can both transport concurrently within the semiconducting channel. However, existing AAT-based devices utilize predominately 2D or organic materials, which are unstable for large-scale semiconductor device integration. Also, their frequency characteristics and energy efficiency have rarely been explored.

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Study observes a room-temperature nonlinear Hall effect in elemental bismuth thin films
https://techxplore.com/news/2024-02-roo ... ffect.html
by Ingrid Fadelli , Tech Xplore

After the advent of 5G, engineers have been trying to devise techniques to further enhance wireless communication technology. To increase these systems' data transmission rate, they will ultimately need to extend their carrier frequency beyond 100 gigahertz, reaching the terahertz range.

Existing devices and technologies, however, have proved to be unable to achieve such high carrier frequencies. One proposed solution to reach this goal entails the use of some quantum materials that exhibit the so-called non-linear Hall effect.

Researchers at Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V. and University of Salerno have identified a promising material for the development of next generation wireless communication systems, namely thin film elemental bismuth. Their paper, published in Nature Electronics, shows that this material exhibits a room-temperature nonlinear Hall effect.

"Other teams had already created various materials that exhibit the non-linear Hall effect, but they do not combine all the technologically desirable properties like simple and environmentally friendly chemical composition, room temperature operation and possibility to be prepared on substrates suitable for micro- and flexible electronics," Denys Makarov and Carmine Ortix, co-authors of the paper, told Tech Xplore.

"Graphene, for example, is environmentally safe and its non-linear Hall effect can be controlled well, but only at temperatures below around -70 degrees Celsius. This means that if the researchers want to use the effect, they have to cool it down with liquid nitrogen."

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Diamond nanomembranes make electronics 10x cooler, 5x faster to charge
By Michael Irving
March 04, 2024

https://newatlas.com/materials/diamond- ... ectronics/
Fraunhofer scientists have used ultra-thin diamond membranes to drastically cool electronic components and boost electric vehicle charging speeds, taking advantages of diamond's excellent thermal conductivity..

Heat is usually an unfortunate side effect of electricity, and too much of it can damage components and devices, sometimes in dangerous ways. As such, managing and removing heat is a major consideration in electronics design, with heat sinks usually made of copper or aluminum. The problem is, these metals are also good conductors of electricity, so another insulating layer is usually needed. So for the new study, the Fraunhofer team turned to diamond, which is an excellent conductor of heat but an insulator for electricity.

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3D reflector microchips could speed development of 6G wireless
https://techxplore.com/news/2024-03-3d- ... eless.html
by Cornell University

Cornell University researchers have developed a semiconductor chip that will enable ever-smaller devices to operate at the higher frequencies needed for future 6G communication technology.

The next generation of wireless communication not only requires greater bandwidth at higher frequencies—it also needs a little extra time. The new chip adds a necessary time delay so signals sent across multiple arrays can align at a single point in space— without disintegrating.

The team's paper, "Ultra-Compact Quasi-True-Time-Delay for Boosting Wireless Channel-Capacity," was published March 6 in Nature. The lead author is Bal Govind, a doctoral student in electrical and computer engineering.

The majority of current wireless communications, such as 5G phones, operate at frequencies below 6 gigahertz (GHz). Technology companies have been aiming to develop a new wave of 6G cellular communications that use frequencies above 20 GHz, where there is more available bandwidth, which means more data can flow and at a faster rate. 6G is expected to be 100 times faster than 5G.

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Researchers develop a new strategy to enhance blue perovskite LED performance
https://phys.org/news/2024-03-strategy- ... skite.html
by University of Science and Technology of China

Prof. Cui Linsong's research team from the University of Science and Technology of China (USTC), cooperating with Prof. Samuel D. Stranks' team from the University of Cambridge, devised a novel strategy to enhance the performance of blue light-emitting diodes (LEDs) based on perovskite materials. Their work has been published in Nature Photonics.

Perovskite LEDs have emerged as a promising next-generation technology for lighting and displays due to their superior luminescent properties and cost-effectiveness. While significant progress has been made in green, red, and near-infrared perovskite LEDs, the development of blue perovskite LEDs has lagged behind, posing a major bottleneck in the field.

To address this challenge, the research team designed a multifunctional ionic additive, Bis(triphenylphosphine)iminium chloride (PPNCl), with multiple charged resonance forms and a dynamic electronic state. This compound enables precise control over the composition and distribution of perovskite phases, effectively suppressing non-radiative recombination channels and ion migration, thereby significantly improving the efficiency and stability of blue perovskite LEDs.

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Quantum interference could lead to smaller, faster, and more energy-efficient transistors
https://phys.org/news/2024-03-quantum-s ... cient.html
by Queen Mary, University of London

An international team of researchers from Queen Mary University of London, the University of Oxford, Lancaster University, and the University of Waterloo have developed a new single-molecule transistor that uses quantum interference to control the flow of electrons. The transistor, which is described in a paper published in the Nature Nanotechnology, opens new possibilities for using quantum effects in electronic devices.

Transistors are the basic building blocks of modern electronics. They are used to amplify and switch electrical signals, and they are essential for everything from smartphones to spaceships. However, the traditional method of making transistors, which involves etching silicon into tiny channels, is reaching its limits.

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BREAKTHROUGH CMOS N-Type Diamond Transistors
March 28, 2024 by Brian Wang

Diamond CMOS needs symmetrical doping control like we have for semiconductor silicon and diamond n-MOS is needed. The n-channel diamond MOSFETs are demonstrated. This work will enable the development of energy-efficient and high-reliability CMOS integrated circuits for high-power electronics, integrated spintronics, and extreme sensors under harsh environments.


Currently, p-channel diamond MOSFETs have been extensively developed and a routine fabrication process has been established. Owing to the lack of diamond n-MOSs, a complementary circuit has been reported to be accomplished using diamond p-MOSs and III-nitride n-MOSs. Although this is a promising strategy, all-diamond CMOS is the ultimate pursuit to fully exploit the figure-of-merit of diamond, particularly for electronics that operate under harsh environments (high temperatures and strong radiation).

https://www.nextbigfuture.com/2024/03/b ... stors.html

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Using a 2D perovskite oxide as a photoactive high-κ gate dielectric
https://techxplore.com/news/2024-03-2d- ... -high.html
by Ingrid Fadelli , Tech Xplore

Two-dimensional (2D) superconducting materials have been found to be promising for the development of miniaturized optoelectronic devices. To perform well while consuming less energy, however, these smaller devices require a higher gate capacitance (i.e., gates that can store more electrical charge in proportion to the voltage applied).

One approach to boost gate capacitance without decreasing the thickness of gate insulators or gate dielectrics entails the use of insulating materials with a high dielectric constant (κ), such as hafnium oxide (HfO2). While this could be an advantageous solution, these materials have proved to be difficult to integrate with 2D semiconductors.

Researchers at Fudan University recently prepared a 2D perovskite oxide with high-κ that can be integrated with different 2D channel materials. Their paper, published in Nature Electronics, could open new opportunities for the future down-scaling of optoelectronics.

"High dielectric constant (high-κ) gate dielectrics compatible with two-dimensional (2D) semiconductors are essential for scaled optoelectronic devices," Siyuan Li, Xinya Liu and their collaborators wrote in their paper.

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A new strategy for fabricating high-density vertical organic electrochemical transistor arrays
https://techxplore.com/news/2024-03-str ... tical.html
by Ingrid Fadelli , Tech Xplore

Organic electrochemical transistors (OECTs) are an emerging class of transistors based on organic superconducting materials known for their ability to modulate electrical current in response to small changes in the voltage applied to their gate electrode. Like other electronics based on organic semiconductors, these transistors could be promising for the development of various brain-inspired and wearable technologies.

OECTs have various notable advantages, including promising amplification and sensing capabilities. low driving voltages, and a versatile structure. Despite these advantages, most conventional OECTs developed so far have been found to exhibit various limitations, including limited stability and slow redox processes, which can significantly impair their performance.

Researchers at Northwestern University recently outlined a new strategy to fabricate high-density and mechanically flexible OECTs. Their proposed approach, outlined in a paper in Nature Electronics, was used to create various electronic components based on OECT arrays and circuits.

"Organic electrochemical transistors (OECTs) can be used to create biosensors, wearable devices, and neuromorphic systems," Jaehyun Kim, Robert M. Pankow, and their colleagues wrote in their paper.

"However, restrictions in the micro- and nanopatterning of organic semiconductors, as well as topological irregularities, often limit their use in monolithically integrated circuits. We show that the micropatterning of organic semiconductors by electron-beam exposure can be used to create high-density (up to around 7.2 million OECTs per cm2) and mechanically flexible vertical OECT arrays and circuits."

To fabricate their OECT arrays, Kim, Pankow, and their colleagues first exposed both p- and n-channel organic semiconductor films to a direct beam of electrons. This method, known as electron beam lithography (eBL), allowed them to produce a pattern on the semiconducting films without employing masks or chemical solvents that could damage the materials. This made the films electronically inactive (i.e., insulating) without affecting their ability to conduct ions.

The patterned films resulting from this process were ultra-small and high-density while also presenting well-defined, conducting channel regions. Moreover, the eBL strategy employed by the researchers enabled the effective multilayer integration of OECT structures into arrays and circuits.