MIT News April 27, 2023 Semiconductor chips are traditionally made with bulk materials, which are boxy 3D structures, so stacking multiple layers of transistors to create denser integrations is very difficult. Semiconductor transistors made from ultrathin 2D materials, each only about three atoms in thickness, could be stacked up to create more powerful chips. Using a low-temperature growth process that does not damage the chip, an international team of researchers (USA – MIT, Oak Ridge National Laboratory, Sweden) has demonstrated a novel technology that can effectively and efficiently “grow” layers of 2D transition metal dichalcogenide (TMD) materials directly on top […]
Tag Archives: transistors
Easy-to-make, ultra-low power electronics could charge out of thin air
Nanowerk October 14, 2020 An international team of researchers (China, UK, Saudi Arabia) has developed a technology that delivers high-performance electronic circuits based on thin-film transistors which are ‘ambipolar’ in deep subthreshold region. The ‘deep-subthreshold ambipolar’ refers to unprecedented ultra-low operating voltages and power consumption levels. They created printed electronics that meet the power and voltage requirements of real-world applications and opened opportunities for remote sensing and ‘place-and-forget’ devices that can operate without batteries for their entire lifetime. The ultra-low-power printed electronics are simple and cost-effective to manufacture. It can be scaled up to make inexpensive battery-less devices that could […]
NIST scientists create new recipe for single-atom transistors
EurekAlert May 11, 2020 Using a room temperature grown locking layer and precise control over the entire fabrication process, a team of researchers in the US (NIST, University of Maryland) reduced unintentional dopant movement while achieving high quality epitaxy in scanning tunneling microscope (STM)-patterned devices. They demonstrated the exponential scaling of the tunneling resistance on the tunnel gap as it is varied from 7 dimer rows to 16 dimer rows, the capability to reproducibly pattern devices with atomic precision and a donor-based fabrication process where atomic scale changes in the patterned tunnel gap result in the expected changes in the […]
Researchers demonstrate a platform for future optical transistors
EurekAlert April 9, 2020 The inability of photons to interact well with each other is a drawback in developing optical transistors. An international team of researchers (Russia, Iceland, UK) demonstrated a new efficient implementation, where photons couple to excitons in single-layer semiconductors. They created polaritons with the help of a laser, a waveguide, and an extremely thin molybdenum diselenide semiconductor layer trapping them in the system. Polaritons obtained in this way not only exist for relatively long periods of time, but also have extra high nonlinearity, meaning that they actively interact with each other. The work brings us closer to […]
Scientists create fully electronic 2-D spin transistors
Nanowerk September 17, 2019 Using gold electrodes, researchers in the Netherlands were able to send a pure charge current through graphene and generate a spin current, referred to as the Rashba-Edelstein effect. This happens due to the interaction with the heavy atoms of the TMD monolayer (in this case, tungsten disulfide). The charge current induces a spin current in the graphene, which they could measure with spin-selective ferromagnetic cobalt electrodes. The charge-to-spin conversion makes it possible to build all-electrical spin circuits with graphene. They showed that the efficiency of the generation of the spin accumulation can be tuned by the […]
Single-electrode material streamlines functions into a tiny chip
Phys.org July 29, 2019 An international team of researchers (Saudi Arabia, USA – Georgia Institute of Technology) has demonstrated transistor‐level integration of electrochemical microsupercapacitors and thin film transistor rectifiers using ruthenium oxide as the common electrode material connecting all devices in the microcircuits. Thin film rectifiers are shown to be capable of rectifying AC signal input from either triboelectric nanogenerators or standard function generators. They exhibit exceptionally slow self‐discharge rate and sufficient power to drive various electronic devices. The study opens a new avenue for developing compact on‐chip electrochemical micropower units integrated with thin film electronics, simplifying device fabrication and […]
Researchers ‘stretch’ the ability of 2-D materials to change technology
Phys.org June 10, 2019 An international team of researchers (USA – University of Rochester, China) developed a platform and deposited a flake of molybdenum ditelluride (MoTe2) onto a ferroelectric material. When voltage is applied to the ferroelectric—which acts like a transistor’s third terminal, the 2-D material by the piezoelectric effect, causing it to stretch. When stretched, by about 0.4 percent, and unstretched, the MoTe2 changes from a low conductivity semiconductor material to a highly conductive semi metallic material and back again. It operates just like a field effect transistor. The process works at room temperature and requires only a small […]
Beyond 1 and 0: Engineers boost potential for creating successor to shrinking transistors
Eurekalert May 29, 2019 Through theory, design and simulations an international team of researchers (South Korea, USA – UT Dallas) developed the fundamental physics of a multi-value logic transistor that uses a novel configuration of two forms of zinc oxide combined to form a composite nanolayer, which is then incorporated with layers of other materials in a superlattice. The device is capable of two electronically stable and reliable intermediate states between 0 and 1, boosting the number of logic values per transistor from two to three or four. The multi-value transistors exhibited excellent performance characteristics, stable and reliable operation with […]
China Publishes Research on Competitive 3-Nanometer Chip
Next Big Future May 29, 2019 Researchers in China have fabricated high-performance negative capacitance p-type FinFETs (p-FinFETs) with a 3-nm-thick ferroelectric (FE) hafnium zirconium oxides layer based on a conventional high-κ metal gate FinFETs fabrication flow. The devices show improved subthreshold swing values and slight hysteresis voltages with the integrated FE film and a strong driving current enhancement (up to 260%) is also obtained compared with that of conventional FinFETs. The inherent reasons for the improved characteristics contribute to the low-interface state density and perfect channel electrostatic integrity. Samsung, Intel and Taiwan Semiconductor will be commercially producing 3-nanometer chips in […]
One transistor for all purposes
Nanowerk March 19, 2019 Until now, organic semiconductors have failed to achieve high performance in highly integrated sub-100 nm transistors. Using a vertical field-effect transistor design with a channel length of only 40 nm and a footprint of 2 × 80 × 80 nm2, researchers in Germany show that high electrical performance with organic polymers can be realized when using electrolyte gating. These organic transistors combine high on-state current densities of above 3 MA cm−2, on/off current modulation ratios of up to 108 and large transconductances of up to 5,000 S m−1. These structures show promise for use in artificial neural networks, where they could operate as memristive devices with sub-100 fJ […]