A5006993282- Semiconductor materials and devices
- Advanced Memory and Neural Computing
- Advancements in Semiconductor Devices and Circuit Design
- Ferroelectric and Negative Capacitance Devices
- Semiconductor materials and interfaces
- Thermal Radiation and Cooling Technologies
- Electronic and Structural Properties of Oxides
- Graphene research and applications
- 2D Materials and Applications
- Transition Metal Oxide Nanomaterials
- Integrated Circuits and Semiconductor Failure Analysis
- Urban Heat Island Mitigation
- MXene and MAX Phase Materials
- Metamaterials and Metasurfaces Applications
- Quantum and electron transport phenomena
- Nanowire Synthesis and Applications
- Photoacoustic and Ultrasonic Imaging
- Silicon Nanostructures and Photoluminescence
- Perovskite Materials and Applications
- Immunotherapy and Immune Responses
- Neuroscience and Neural Engineering
- Cancer Immunotherapy and Biomarkers
- Building Energy and Comfort Optimization
- CCD and CMOS Imaging Sensors
- Molecular Junctions and Nanostructures
Peking University
2011-2024
Beijing Advanced Sciences and Innovation Center
2022-2024
Anhui Medical University
2022-2023
University of California, Berkeley
2019-2022
Lawrence Berkeley National Laboratory
2019-2022
Institute of Microelectronics
2020-2021
Tsinghua–Berkeley Shenzhen Institute
2020
Tsinghua University
2020
University of Delaware
2020
University of Hong Kong
2020
By using ab initio calculations, we predict that a vertical electric field is able to open band gap in semimetallic single-layer buckled silicene and germanene. The sizes of the both germanene increase linearly with strength. Ab quantum transport simulation dual-gated effect transistor confirms opens gap, significant switching by an applied gate voltage also observed. Therefore, biased can work effectively at room temperature as transistors.
The sky is a natural heat sink that has been extensively used for passive radiative cooling of households. A lot focus on maximizing the power roof coating in hot daytime using static, cooling-optimized material properties. However, resultant overcooling cold night or winter times exacerbates heating cost, especially climates where dominates energy consumption. We approached thermal regulation from an all-season perspective by developing mechanically flexible adapts its emittance to...
The use of 2D materials to improve the capabilities electronic devices is a promising strategy that has recently gained much interest in both academia and industry. However, while research metallic semiconducting well established, detailed knowledge applications insulators are still scarce. In this paper, presence resistive switching (RS) multilayer hexagonal boron nitride ( h ‐BN) studied using different electrode materials, family ‐BN‐based random access memories with tunable engineered....
Stimulated by the recent experimental synthesis of a new layered carbon allotrope-graphdiyne film, we provide first systematic ab initio investigation structural and electronic properties bilayer trilayer graphdiyne explore possibility tuning energy gap via homogeneous perpendicular electric field. Our results show that most stable both have their hexagonal rings stacked in Bernal way (AB ABA style configuration, respectively). Bilayer with second stacking arrangements direct bandgaps 0.35...
Thermal radiation from a black body increases with the fourth power of absolute temperature (T4 ), an effect known as Stefan-Boltzmann law. Typical materials radiate heat at portion this limit, where portion, called integrated emissivity (εint is insensitive to (|dεint /dT| ≈ 10-4 °C-1 ). The resultant radiance bound by T4 law limits ability regulate radiative heat. Here, unusual material platform shown in which εint can be engineered decrease arbitrary manner near room 8 × 10-3 enabling...
Thermal emission from objects tends to be spectrally broadband, unpolarized, and temporally invariant. These common notions are now challenged with the emergence of new nanophotonic structures concepts that afford on-demand, active manipulation thermal process. This opens a myriad applications in chemistry, health care, management, imaging, sensing, spectroscopy. Here, we theoretically propose experimentally demonstrate approach actively tailor reflective, plasmonic metasurface which...
We provide the first systematic ab initio investigation of possibility to create a band gap in few-layer graphene (FLG) via perpendicular electric field. Bernal (ABA) and arbitrarily stacked FLG remain semimetallic, but rhombohedral (ABC) demonstrates variable gap. The maximum ABC decreases with increasing layer number can be fitted by relationship Δmax = 1/(2.378 + 0.521N 0.035N2) eV. effective masses carriers over wide range around point are comparable that AB bilayer under zero It is...
In order to fulfill the information storage needs of modern societies, performance electronic nonvolatile memories (NVMs) should be continuously improved. past few years, resistive random access (RRAM) have raised as one most promising technologies for future due their excellent and easy fabrication. this work, a novel strategy is presented further extend RRAMs. By using only cheap industry friendly materials (Ti, TiO 2 , SiO X n ++ Si), memory cells are developed that show both filamentary...
Effective passivation of interface defects in high-k metal oxide/Ge gate stacks is a longstanding goal research on germanium metal-oxide-semiconductor devices. In this paper, we use photoelectron spectroscopy to probe the formation GeO2 layer between an atomic deposited Al2O3 dielectric and Ge(100) substrate during forming gas anneal (FGA). Capacitance- conductance-voltage data were used extract trap density energy distribution. These results show selective traps with energies top half Ge...
III–V nanowires are candidate building blocks for next generation electronic and optoelectronic platforms. Low bandgap semiconductors such as InAs InSb interesting because of their high electron mobility. Fine control the structure, morphology, composition key to physical properties. In this work, we present how grow catalyst-free InAs1–xSbx nanowires, which stacking fault twin defect-free over several hundreds nanometers. We evaluate impact crystal phase purity by probing electrical...
Abstract Complementary metal‐oxide‐semiconductor (CMOS) field‐effect transistors (FETs) are the key component of a chip. Bulk indium arsenide (InAs) owns nearly 30 times higher electron mobility µ e than silicon but suffers from much lower hole h ( / = 80), thus unsuited to CMOS application with single material. Through accurate ab initio quantum‐transport simulations, performance gap between NMOS and PMOS is significantly narrowed predicted even vanished in sub‐2‐nm‐diameter gate‐all‐around...
There is a tunable band gap in ABC-stacked few-layer graphene (FLG) via applying vertical electric field, but the operation of FLG-based field effect transistor (FET) requires two gates to create and tune channel's conductance individually. Using first principle calculations, we propose an alternative scheme open FLG namely single-side adsorption. The generally proportional charge transfer density. capability metal adsorption decreases this order: K/Al > Cu/Ag/Au Pt. Moreover, find that even...
Resistance switching in TiO2 and many other transition metal oxide resistive random access memory materials is believed to involve the assembly breaking of interacting oxygen vacancy filaments via combined effects field-driven ion migration local electronic conduction leading Joule heating. These complex processes are very difficult study directly part because form between metallic electrode layers that block their observation by most characterization techniques. By replacing top layer a...
Insulating films are essential in multiple electronic devices because they can provide functionalities, such as capacitance effects and electrical fields. Two-dimensional (2D) layered materials have superb electronic, physical, chemical, thermal, optical properties, be effectively used to additional performances, flexibility transparency. 2D insulators called future devices, but their reliability, degradation kinetics, dielectric breakdown (BD) process still not understood. In this work, the...
By combining differential phase contrast scanning transmission electron microscope (DPC-STEM) and Energy Disperse Spectroscopy (EDS) analysis, the migration of oxygen vacancies evolution built-in field in ferroelectric HfO 2 are observed for first time.
Atomic layer deposited (ALD) TiO2 protection layers may allow for the development of both highly efficient and stable photoanodes solar fuel synthesis; however, very different conductivities photovoltages reported TiO2-protected silicon anodes prepared using similar ALD conditions indicate that mechanisms set these key properties are, as yet, poorly understood. In this report, we study hydrogen-containing annealing treatments find postcatalyst-deposition anneals at intermediate temperatures...
State-of-the-art silicon water splitting photoelectrochemical cells employ oxide protection layers that exhibit electrical conductance in between of dielectric insulators and electronic conductors, optimizing both built-in field conductivity.
In-situ direct ammonia (NH3) plasma nitridation has been used to passivate the Al2O3/SiGe interfaces with Si nitride and oxynitride. X-ray photoelectron spectroscopy of buried interface shows that NH3 pre-treatment should be performed at high temperatures (300 °C) fully prevent Ge oxynitride formation out-diffusion into oxide. C-V I-V results show a lower density traps smaller gate leakage for samples 300 °C.
Thermography detects surface temperature and subsurface thermal activity of an object based on the Stefan-Boltzmann law. Impacts technology would be more far-reaching with finer sensitivity, called noise-equivalent differential (NEDT). Existing efforts to advance NEDT are all focused improving registration radiation signals better cameras, driving number close end roadmap at 20 40 mK. In this work, we take a distinct approach sensitizing against minute variation object. The emissivity...
Abstract Phase-transition materials provide exciting opportunities for controlling optical properties of photonic devices dynamically. Here, we systematically investigate the infrared emission from a thin film vanadium dioxide (VO 2 ). We experimentally demonstrate that such films are promising candidates to tune and control thermal radiation an underlying hot body with different emissivity features. In particular, studied two heat sources completely features, i.e. black body-like...
Properties of semiconductors are largely defined by crystal imperfections including native defects. Van der Waals (vdW) semiconductors, a newly emerged class materials, no exception: defects exist even in the purest materials and strongly affect their electrical, optical, magnetic, catalytic sensing properties. However, unlike conventional where energy levels well documented, they experimentally unknown best studied vdW impeding understanding utilization these materials. Here, we directly...