A5022728913- Semiconductor materials and devices
- Ga2O3 and related materials
- Metal and Thin Film Mechanics
- Force Microscopy Techniques and Applications
- ZnO doping and properties
- GaN-based semiconductor devices and materials
- Microstructure and mechanical properties
- Thermal properties of materials
- 2D Materials and Applications
- Graphene research and applications
- Integrated Circuits and Semiconductor Failure Analysis
- Carbon Nanotubes in Composites
- Advanced MEMS and NEMS Technologies
- Nanowire Synthesis and Applications
- Ion-surface interactions and analysis
- Mechanical and Optical Resonators
- Copper Interconnects and Reliability
- Electromagnetic Effects on Materials
- MXene and MAX Phase Materials
- Advanced Surface Polishing Techniques
- Nuclear Materials and Properties
- Semiconductor materials and interfaces
- Advanced Sensor and Energy Harvesting Materials
- Diamond and Carbon-based Materials Research
- Silicon Carbide Semiconductor Technologies
Pennsylvania State University
2016-2025
Park University
2023-2024
Dhaka International University
2023
University of Florida
2022
Argonne National Laboratory
2022
United States Naval Research Laboratory
2022
University of Central Florida
2022
National Academies of Sciences, Engineering, and Medicine
2022
Impulse Dynamics (United States)
2021
University of Canberra
2020
Solution-processable ferroelectric polymer nanocomposites are developed as a new form of electrocaloric materials that can be effectively operated under both modest and high electric fields at ambient temperature. By integrating the complementary properties constituents, exhibit state-of-the-art cooling energy densities. Greatly improved thermal conductivity also yields superior power densities validated by finite volume simulations.
Atomically thin transition metal dichalcogenides (TMDs) are of interest for next-generation electronics and optoelectronics. Here, we demonstrate device-ready synthetic tungsten diselenide (WSe2) via metal-organic chemical vapor deposition provide key insights into the phenomena that control properties large-area, epitaxial TMDs. When epitaxy is achieved, sapphire surface reconstructs, leading to strong 2D/3D (i.e., TMD/substrate) interactions impact carrier transport. Furthermore, substrate...
Uniform growth of pristine two dimensional (2D) materials over large areas at lower temperatures without sacrifice their unique physical properties is a critical pre-requisite for seamless integration next-generation van der Waals heterostructures into functional devices. This Letter describes vapor phase technique precisely controlled synthesis continuous, uniform molecular layers MoS2 on silicon dioxide and highly oriented pyrolitic graphite substrates several square centimeters 350 °C....
We have added force and displacement measurement capabilities in the transmission electron microscope (TEM) for situ quantitative tensile experimentation on nanoscale specimens. Employing technique, we measured stress-strain response of several free-standing aluminum gold films subjected to loading unloading cycles. observed low elastic modulus, nonlinear elasticity, lack work hardening, macroscopically brittle nature these metals when their average grain size is 50 nm or less. Direct TEM...
Multiferroic laminate composites consisting of chain-end cross-linked ferroelectric polymers and magnetostrictive Metglas are reported. The exhibit a greatly enhanced multiferroic voltage coefficient sensitivity relative to analogous composites. These remarkable properties attributed high piezoelectric electromechanical coupling coefficients, because the formation larger crystalline sizes concurrent improvement in polarization ordering polymers.
The wide bandgap semiconductors SiC and GaN are already commercialized as power devices that used in the automotive, wireless, industrial markets, but their adoption into space avionic applications is hindered by susceptibility to permanent degradation catastrophic failure from heavy-ion exposure. Efforts space-qualify these have revealed they susceptible damage high-energy, radiation environment (galactic cosmic rays) cannot be shielded. In space-simulated conditions, transistors shown at...
We present a micro-electro-mechanical system-based experimental technique to measure thermal conductivity of freestanding ultra-thin films amorphous silicon nitride (Si3N4) as function mechanical strain. Using combination infrared micrography and multi-physics simulation, we measured 50 nm thick observe it decrease from 2.7 W (m K)−1 at zero strain 0.34 about 2.4% tensile propose that such strong strain–thermal coupling is due effects on fraction–phonon interaction decreases the dominant...
Classical fracture mechanics as well modern strain gradient plasticity theories assert the existence of stress concentration (or gradient) ahead a notch tip, albeit somewhat relaxed in ductile materials. In this study, we present experimental evidence extreme homogenization nanocrystalline metals that result immeasurable amount at tip. We performed situ uniaxial tension tests 80 nm thick (50 average grain size) freestanding, single edge notched aluminum specimens inside transmission electron...
Low-angle grain boundaries (LAGBs) accommodate residual stress through the rearrangement and accumulation of dislocations during cold rolling. This study presents an electron wind force-based annealing approach to recover cold-rolling induced in FeCrAl alloy below 100 °C 1 min. is significantly lower than conventional thermal annealing, which typically requires temperatures around 750 for about 1.5 h. A key feature our athermal force effect, promotes dislocation movement relief at...
High-power electronics, such as GaN high electron mobility transistors (HEMTs), are expected to perform reliably in high-temperature conditions. This study aims gain an understanding of the microscopic origin both material and device vulnerabilities temperatures by real-time monitoring onset structural degradation under varying temperature is achieved operating HEMT devices situ inside a transmission microscope (TEM). Electron-transparent specimens prepared from bulk heated up 800 °C....
Small size scale and high resolutions in force displacement measurements make MEMS actuators appropriate for micromechanical testing. In this paper, the first time, we present methodologies uniaxial tensile cantilever bending testing of both micrometer- submicrometer-scale freestanding specimens using actuators. We also introduce dry fabrication processes specimens. The allow single or multilayered thin-film to be fabricated separately from For tension test, forces are applied by lateral...
Carbon nanotubes and nanofibers are extensively researched as reinforcing agents in nanocomposites for their multifunctionality, light weight high strength. However, it is the interface between nanofiber matrix that dictates overall properties of nanocomposite. The current trend to measure elastic bulk nanocomposite then compare them with theoretical models extract information on interfacial ideal experiment single fiber pullout from because directly measures technique difficult apply small...