Nanowerk April 11, 2024 The exact role of h-BN encapsulation in relation to the internal defects of 2D semiconductors in hexagonal boron nitride (h-BN) remains unclear. An international team of researchers (South Korea, Japan) reported that h-BN encapsulation greatly removes the defect-related gap states by stabilizing the chemisorbed oxygen molecules onto the defects of monolayer tungsten disulfide (WS2) crystals. Studies showed that h-BN encapsulation prevented the desorption of oxygen molecules over various excitation and ambient conditions, resulting in a greatly lowered and stabilized free electron density in monolayer WS2 crystals. This suppressed the exciton annihilation processes by two orders of […]
Category Archives: Semiconductor
A superatomic semiconductor sets a speed record
Science Daily October 26, 2023 The transport of energy and information in semiconductors is limited by scattering between electronic carriers and lattice phonons, resulting in diffusive and lossy transport that curtails all semiconductor technologies. Researchers at Columbia University used Re6Se8Cl2, a superatomic semiconductor, to demonstrate the formation of acoustic exciton-polarons. They directly imaged polaron transport in Re6Se8Cl2 at room temperature, revealing quasi-ballistic, wavelike propagation sustained for a nanosecond and several micrometers. Shielded polaron transport led to electronic energy propagation lengths orders of magnitude greater than in other vdW semiconductors, exceeding even silicon over a nanosecond. According to the researchers quasi-flat […]
Breaking through the limits of stretchable semiconductors with molecular brakes that harness light
Science Daily June 9, 2023 Researchers in South Korea investigated the effects of an azide photocrosslinker’s molecular length and structure on the microstructural, electrical features, and stretchability of photocrosslinked conjugated polymer films. For a systematic comparison, they synthesized a series of nitrene-induced photocrosslinkers (n-NIPSs) with different numbers of ethylene glycol repeating units (n = 1, 4, 8, 13) that bridge two tetrafluoro-aryl azide end groups. Two semicrystalline conjugated polymers and two nearly amorphous conjugated polymers were co-processed with n-NIPSs and crosslinked by brief exposure to UV light. They found that among the synthesized n-NIPSs, the shortest one (1-NIPS) is the […]
Modified microwave oven cooks up next-gen semiconductors
Nanowerk September 9, 2022 The doped semiconductor material must be sufficiently stable for the fabrication and operation of electronic devices. An international team of researchers (USA – Cornell University, industry, Taiwan, Spain) theorized that microwaves could be used to activate the excess dopants, but the previous microwave annealers produced “standing waves” that prevented consistent dopant activation. According to the researchers this discovery could be used to produce semiconductor materials and electronics appearing around the year 2025. It can potentially enable leading manufacturers to scale down to just 2 nanometers…read more. TECHNICAL ARTICLE
Researchers explore a hydrodynamic semiconductor where electrons flow like water
Phys.org July 20, 2022 An international team of researchers (USA – Columbia University, Cornell University, Brown University, Singapore, Japan) combined theoretical and experimental study of ambipolar hydrodynamic transport in bilayer graphene to demonstrate that the conductivity is given by the sum of two Drude-like terms that describe relative motion between electrons and holes, and the collective motion of the electron-hole plasma. As predicted, the measured conductivity of gapless, charge-neutral bilayer graphene was sample- and temperature-independent over a wide range. Away from neutrality, the electron-hole conductivity collapsed to a single curve, and a set of just four fitting parameters provided quantitative […]
The Chip Shortage, Giant Chips, and the Future of Moore’s Law IEEE Spectrum’s
IEEE Spectrum December 28, 2021 To recap the semiconductor stories, we have read most this year, IEEE has put together this set of highlights…read more.
A gold butterfly can make its own semiconductor skin
Science Daily February 6, 2020 Current methods for placing nano-sized semiconductors on metallic particles to utilize them in nano-lasing and nano-lithography lack precision or are too costly. Researchers in Japan have developed a method based on a hydrothermal synthesis reaction to locally and selectively synthesize zinc oxide in a plasmonic nanoantenna. They first made evident the role of localized surface plasmon resonances (LSPR) for achieving efficient heating of gold nanostructures. Then, by selectively addressing one of the LSPRs of a gold antenna, they demonstrated that localized zinc oxide formation at the targeted location of the antenna can be achieved due […]
Chipmakers Test Ferroelectrics as a Route to Ultralow-Power Chips
IEEE Spectrum February 26, 2018 Researchers at a company in the US chose a ferroelectric material that does not require ions or atoms to relocate which slows things down in ferroelectric materials. In their experimental 14-nm transistors, clouds of electrons around silicon-doped hafnium dioxide experience the polarization. Ring oscillators made with these transistors can switch at the same frequency as those made with the usual recipe, yet they require just 54 mV to achieve a tenfold increase in the current. Their devices require a 3- to 8-nm-thick layer of ferroelectric material, which is still relatively thick… read more. Related TECHNICAL […]
New center to develop next-generation computing technologies
Nanowerk January 15, 2018 Applications and Systems-driven Center for Energy-Efficient integrated Nano Technologies (ASCENT) led by the University of Notre Dame will pursue four areas of technology including three-dimensional integration of device technologies beyond a single planar layer (vertical CMOS); spin-based device concepts that combine processing and memory functions (beyond CMOS); heterogeneous integration of functionally diverse nano-components into integrated microsystems (heterogeneous integration fabric); and hardware accelerators for data intensive cognitive workloads (merged logic-memory fabric). ASCENT is funded by Semiconductor Research Corporation… read more.