A5008558923- Advancements in Semiconductor Devices and Circuit Design
- Integrated Circuits and Semiconductor Failure Analysis
- Semiconductor materials and devices
- Advanced Photocatalysis Techniques
- TiO2 Photocatalysis and Solar Cells
- Mechanical and Optical Resonators
- Quantum Dots Synthesis And Properties
- Topological Materials and Phenomena
- Carbon Nanotubes in Composites
- Analytical Chemistry and Sensors
- Quantum and electron transport phenomena
- Graphene research and applications
- Silicon and Solar Cell Technologies
- Advanced Thermoelectric Materials and Devices
- Semiconductor Quantum Structures and Devices
- Surface and Thin Film Phenomena
- Gas Sensing Nanomaterials and Sensors
- ZnO doping and properties
- Thermal properties of materials
- Semiconductor materials and interfaces
- Acoustic Wave Resonator Technologies
- Advanced Chemical Sensor Technologies
- Molecular Junctions and Nanostructures
- Scientific Research and Discoveries
- Advanced Semiconductor Detectors and Materials
National Institute for Research and Development in Microtechnologies
2003-2025
Honeywell (Romania)
2006-2015
University of Bucharest
2015
Sensors (United States)
2015
Honeywell (United States)
2008-2009
National Institute For Chemical Pharmaceutical Research and Development
2002
Center of Technology and Engineering for Nuclear Projects
1986
University of Minnesota
1983-1984
Temperature dependence of the 1/f noise intensity in Bi2Se3 features a weak structure unknown origin. Comparing with Raman spectrum Bi2Se3, we found that it is image surface phonon this topological insulator. It also revealed low both bands composing regime due to interaction Dirac electrons phonons Bi2Se3. One these has been correspond boson peak amorphous Se atoms, while other one well fitted by Eliashberg function Bi. indicates thermal motion and Bi first second atomic layers quintuple...
A new D–π–A dye based on dihexyloxy-substituted triphenylamine moiety has been synthesized and its preliminary performances in DSSCs are reported.
Four dyes consisting of a phenoxazine–triphenylamine double-donor assembly, on which one to four cyanoacrylic acid acceptor groups were grafted, have been synthesized and characterized. The UV–vis measurements revealed complex intramolecular charge transfer, feature supported by the density functional theory calculations. We found that both highest occupied molecular orbitals lowest unoccupied negatively shift as more anchors are attached donor core, leading an increase dye Mulliken absolute...
Existing experimental data for the temperature dependence of 1/f noise in both n- and p-channel MOS transistors are heuristically compared with either bulk or surface phonon spectra them. It is found that structure mirrors different van Hove singularities spectra. This thought to be signature phonons transistor. For a Debye spectrum, an intriguing 1/τ distribution obtained. The famous connection between oxide states can understood terms scattering if tunneling inelastic. Striking...
Two 1/f noise peaks were found in a carbon soot resistor at voltages characteristic of Kohn anomalies graphite. The ratio the electron-phonon coupling matrix elements calculated from peak intensities is same as one obtained Raman frequencies. This demonstrates that microscopic source soot. A new, very general formula was deduced for frequency exponent, wherein nonlinearity and dispersion are only ingredients. interplay between this describes sublinear-supralinear transitions experimentally...
The synthesis of two new types nanocomposite matrices, the first based on polyallylamine (PAA) and aminocarbon nanotubes, second polyethyleneimine (PEI) are reported. surface acoustic wave (SAW) sensors, coated with selected nanocomposites, showed good sensitivities when varying CO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> concentrations in range (500–5000)ppm. sensor sensitivity is larger using nanotubes than case only a pure...
Interface state density (D <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">it</sub> ) at SiO xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /4H-SiC interfaces is investigated using capacitance-voltage (C-V) characterization. Two different measurement methods for D determination (both C-V temperatures in the range of 80-300K and high frequency (HF) vs quasi static (QS) characteristics) have been used. A significant reduction observed, almost...
In topological insulators, such as (Bi,Sb)2Te3 and BiSbTeSe1.6, the 1/f noise intensity features intriguing peaks, which develop at some specific temperatures. search for their microscopic origin, we compared this structure with either phonon density of states or Raman spectrum each insulator (TI), respectively. (Bi,Sb)2Te3, comparison revealed that peaks track van Hove singularities in states. The most intense peak observed 50 K is attributed to thermal motion Bi atoms. Other less are...
Synthesis of a new type calixarene-doped polyaniline (PANI) is reported. Polyaniline as free base (emeraldine) was synthesized by chemical method, in the presence HCl and ammonium peroxodisulphate oxidant. PANI doped with p-sulfonatocalix|4|arene. The structure protonic acid doped- investigated infrared UV-VIS spectroscopies. spectral features dopant are found polyaniline. exhibits enhanced solubility dimethyl for mamide N-methyl pyrrolidon, which useful sensing
Hard Soft Acid Base (HSAB) theory is introduced as a new tool to select ligands (molecules) for quantum dot covalent functionalization. According HSAB, only soft acid-soft base bond covalent. Since most of the transition metal semiconductor cations on surface dots are acids, approach we propose anchors which bases. Following this strategy, suitable modification selected. Moreover, plethora bifunctional assembling onto titania identified among existing molecules. The functionalization...
We show that the sensitivity of metal-oxide gas sensors to a given peaks at temperatures which correspond specific oxide phonon energies. It indicates atomic vibrations contribute sensing mechanism and explains dependence on exposed facet. In addition, signature molecular in is reported. Lattice anharmonicity as ingredient shaping peak introduced. The existence resonant charge transfer when frequency matches vibration one brought fore.
From our method of phonon density states superposition it is inferred that a possible connection between 1/f noise parameter and the Eliashberg function could exist. According to this hypothesis, temperature dependence would follow energy function. The existing data for tin(Sn). polycrystalline aluminum(Al) copper(Cu) nanobridge are compared with corresponding functions. Striking resemblances found.
It is the purpose of this paper to show expectations, challenges and initial steps concerning realization resonant chemical NEMS sensors able meet needs future applications. Here, we focus on functionalization principles sensing Self-Assembled Monolayer (SAM), modeling simulation CMOS-SOI sensor with electrostatic actuation MOSFET detection, first experimental results for making Si nano wire piezoresistive detection schemes, noise limits nano-sensors, design on-chip readout circuitry,...
For some applications (e.g.: mixers, oscillators), the 1/f noise upconversion limits microwave performances of all kinds HEMTs. That is why origin in HEMTs highly needed. Previously it has been suggested that channel main source at low drain bias. Recent experiments performed on different HEMT's structures indicated InAlAs spacer and buffer as sources noise. Some these also pointed to heterointerfaces All quite clearly established topology sources. A step further would be answer which...