- Themes:
- Nanoelectronics, MEMs and NEMs, Quantum Electronics and Spintronics
- Funding:
- CONACyT, Mexico
As one of promising candidates for a scalable non-volatile memory, we proposed a new suspended-gate silicon nanodot memory (SGSNM) by co-integrating nanoelectromechanical systems (NEMS) and conventional MOSFETs. The SGSNM consists of a MOSFET as readout, silicon nanodots (SiNDs) as a floating gate (FG), and a movable suspended gate (SG) which is isolated from the FG by an air gap and a thin oxide layer. The advantages of the SGSNM cell over the typical flash memory include high speed programming/erasing operations, virtually no gate leakage current and therefore a serious non-volatility, thanks to the presence of the air gap except for the program/erase processes. For programming the SGSNM cell, a negative gate voltage is applied, and the SG is pulled-in on the FG layer, resulting in electron injection from the SG into the FG. For erasing the cell, a positive voltage is applied, and the stored electrons are extracted from the FG.
Primary investigators
- magr07r
- hm2
- Yoshishige Tsuchiya
Partners
- Hitachi Central Research Laboratory
- Tokyo Institute of Technology
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2009-2011
- Theme:
- Nanoelectronics
Carbon Nanotubes have generated a great deal of interest due to their extraordinary mechanical, thermal and electronic properties and they are being researched as a potential replacement for Si for future electronic devices. However, there are significant problems in nanotube growth, positioning and contacting that remain to be solved.
Previous work involving electrodeposition of Ni on Si has shown that the characteristics of the schottky barrier formed are superior to those formed by evaporation. Palladium has been shown to form very good contacts to carbon nanotubes. By electrodepositing PdNi alloys, it may be possible to get ferromagnetic contacts to nanotubes with superior contacting properties compared to current methods.
This project will investigate the use of electrodeposited PdNi metallic contacts to carbon nanotubes and investigate if this method results in the formation of better contacts as compared to evaporated alloys. The presence of Ni in the alloys will also allow a study magnetoresistance effects in nanotubes with electrodeposited ferromagnetic contacts.
Primary investigator
- aru07r
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2008-2012
The project is aimed to develop micro-fabrication technology including; Fabrication of metal electrodes using various technologies i.e., Ion Beam Mill, lift off method etc. Also the project involves with the development for the fabrication of micro-fluidic structure using dry film resist photo resist and SU8 negative photoresist. The project is also concentrating on hot embossing (HE)method using EVG 520 boder for the fabrication of fluidic structure on different polymers such as COC. COP, PMMA and others using Ni, Si, and soft HE stamps. Also the sealing and aligned bonding of micro-fluidic structure is being carried out using thermal bonding and UV glue bonding technology by using EVG 620 mask aligner and EVG bonder.
Primary investigators
- Prof Hywel Morgan
- Dr Matt Mowlem
Associated research group
- Nano Research Group
a) The 3D architecture of suspended nano-dot involved in single-elecron transistor charge-based sensor. b) SEM image of a fabricated sample in collaboration with Tokyo Institute of Technology).
- Date:
- 2008-2012
- Themes:
- Nanoelectronics, MEMs and NEMs, Bionanotechnology and Biosensors
- Funding:
- EUFP7
Precise detection of different species of chemical or biomolecules is fundamental to a vast variety of applications including medical science and environmental studies. Typically, a sensor is exposed to a sample to spot the possible existence of target molecules. The sample can be a gas or liquid possibly containing the target and even some other species. So, it may be required to make the sensor sensitive only to the proposed target molecules by functionalisation. Besides, achieving higher sensitivities is always appreciated. Some applications depend tightly on the time needed for the detection. Therefore, detection speed can be considered as a constraint. This factor can be affected by the type and number of stages involved in the detection procedure.
In order to satisfy the required sensitivity and speed, electrochemical transduction method was selected. Two different approaches are studied as the sensing mechanism. First, a suspended silicon nanowire is used as the channel of a field effect transistor. Then, by making two constriction areas on the nanowire, the architecture is transformed into a single-electron transistor at the heart of device. The single-electron transistor is utilised as an ultra-sensitive charge-based chemical or biosensor. Thus, the ability to sense even a single molecule is provided. In addition, more advanced designs of the single-electron transistor architecture are developed to avoid the necessity of using complex functionalisation methods. Moreover, using silicon on insulator as the implementation platform facilitates the integration of the sensor into the required control circuitry. This work is supported by EU FP7 NEMSIC project.
Primary investigators
- mag08r
- Yoshishige Tsuchiya
- hm2
Partners
- EPFL
- IMEC-BE
- IMEC-NL
- TUDelft
- CEA-LETI
- Honeywell
- Univ. of Geneva
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2005-
- Theme:
- Nanophotonics and Biomimetics
This project is seeking to explore the effects of two-dimensional (2D) chirality on the light-matter interaction for optical nanomaterials composed entirely of lossless dielectric materials. These novel materials have come to be known as planar chiral materials (PCM). So far we have demonstrated that optical transmission through these PCMs can be polarisation-sensitive and non-reciprocal. The PCM structures we have investigated include diffraction gratings and chiral fractals such as the Peano-Gosper fractal.
Primary investigators
Secondary investigators
- ap011r
- wz02r
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
Previous work on the optical properties of surface-plasmon-polaritons (SPP) has shown them to be promising candidates for the creation of optical and quantum computers, as well as useful components in the creation of new optical metamaterials. Unfortunately before the potential SPPs can be fully realised several problems of both a technical and a physics nature need to be overcome. In particular, the propagation of light pulses in SPP circuits and films is known to be all severely limited by the effects of attenuation in the metal and material in-homogeneity, while issues of quantum coherence have yet to be properly addressed. The aims of this programme are to investigate the fundamental physics of SPPs so that SPP circuits can be developed for high-speed optical computing. We propose to do this by investigating the behaviour of SPPs at low temperatures and in nano-structured films, while also examining ways in which the SPP waves can be amplified or pumped by stimulated emission from non-linear or luminescent optical materials
Primary investigators
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2009-2012
- Themes:
- Nanoelectronics, Nanophotonics and Biomimetics
- Funding:
- _other
Working in partnership with Carl Zeiss SMT Inc., we are developing the capabilities and applications of the worldââ¬â¢s first commercial scanning helium ion microscope (SHIM)- the Zeiss Orion. The larger mass and therefore smaller de Broglie wavelength of helium ions compared to electrons means that the SHIM suffers less from diffraction effects than a scanning electron microscope (SEM). This, combined with the extremely small and bright source (courtesy of the atomically sharp tip at which helium atoms are ionised), and the small interaction volume of the beam in the sample enables sub-nanometer resolution to be achieved along with a depth of field up to 5 times larger than in an SEM. Our system is equipped with an Everhart-Thornley secondary electron detector, giving outstanding resolution and topographical contrast, and a micro channel plate backscattered ion detector which produces images exhibiting excellent materials contrast. To add functionality, the Orion SHIM can also be equipped with:
-A Gas Injection System (GIS) for material deposition using the helium ion source.
-An energy dispersive backscattered ion detector for compositional analysis, capable of detecting monolayers of material deposited on a substrate.
-A Gatan MonoCL cathodoluminescence system, used for material luminescence studies based on excitation by a charged particle.
The four main areas for investigation are:
1. Ion induced luminescence spectroscopy with the Gatan MonoCL system, including tests on materials known to exhibit cathodoluminescence in the visible to near IR range, e.g. quantum dots, fluorescent dyes, followed by investigations into tagging biological samples.
2. Material modification, including direct sputtering by helium ions and the use of the GIS for deposition and etching.
3. Ion scattering spectroscopy for characterisation of thin films and for small particle compositional analysis.
4. Ion induced patterning (direct write lithography).
In addition, we welcome enquiries from other groups with samples that may benefit from the unique characterisation capabilities that the Orion can offer.
Primary investigators
Secondary investigator
- Prof. Marco Starink
Partner
- Carl Zeiss SMT Inc.
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2004-2010
- Themes:
- Nanophotonics and Biomimetics, Photovoltaics and Energy
- Funding:
- SuperGen
The aims of this project are to investigate the optical properties of metal nanoparticles, to the study the interaction of metal nanoparticles with solar cells, and to optimize this interaction to increase the efficiency of silicon solar cells.
Reducing the thickness of silicon solar cells increases carrier collection and decreases material costs. However, thin layers cannot absorb as much light as thicker layers, and so light-trapping schemes are required to improve absorption. Conventional light-trapping techniques are based on surface texturing, and result. Additionally, these techniques often do not perform well in the near-infrared (NIR), where silicon is most weakly absorbing.
Metal nanoparticles can strongly scatter UV, visible and NIR despite being substantially sub-wavelength in size. The wavelength at which maximum scattering occurs can be tuned by modifying the nanoparticle size, shape and composition. We have studied the optical properties of metal nanoparticles using simulations and experimental methods. To fabricate metal nanoparticles we use top-down techniques such as electron-beam lithography, or bottom-up techniques such as thin-film annealing.
Currently we are investigating the interaction of metal nanoparticles with amorphous silicon solar cells. The optical properties of metal nanoparticles are altered by the presence of the silicon layer, and so we wish to study and optimize this effect. To aid this study we are also investigating the interaction of metal nanoparticles with planar dielectric layers, which may have additional applications such as coupling of light to planar waveguides and improved planar concentrators.
Primary investigators
- Darren Bagnall
- tlt04r
- fd07r
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2009-2011
- Theme:
- Microfluidics and Lab-on-a-chip
- Funding:
- Technology Strategy Board
A microfluidic device that uses single cell impedance spectroscopy is being developed as part of a Point of Care system capable of perfoming a full blood count (FBC) from a fingerprick of blood. In particular, this project focuses on the discrimination of the five different white blood cell types. Cells are introduced to the device and flow at high speed through the detection zone of a pair of microelectrodes, from which the differential signal provides information on both cell size and dielectric properties.
Treatment of whole blood with a lysis solution currently allows differentiation between the three main white blood cell types: granulocytes, lymphocytes and monocytes (see figure). One of the project objectives is to distinguish the less abundant eosinophils and basophils from neutrophils in the granulocyte population. Laser illumination of the cells enables comparison with fluorescence measurements of specific cell markers, the current 'gold standard' of cell identification. The ultimate aim is to produce a low-cost, compact impedance sensor that does not rely on the use of fluorescent labelling.
Primary investigators
- vh
- Hywel Morgan
Secondary investigators
- Nicolas Green
- Professor Donna Davies
- Dr Judith Holloway
Partner
- Philips Research
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre
- Date:
- 2008-2011
- Theme:
- MEMs and NEMs
- Funding:
- EUFP7
Silicon-based Nano-Electro-Mechanical (NEM) sensors are getting increasing interest because of their compatibility with ââ¬ÅIn-ICââ¬? integration as well as high sensitivity to a change in mass. The NEM sensors enable to detect a small amount of biological or chemical molecules thanking to their nanoscale dimensions and sensitive frequency response. This project presents design of a newly-proposed In-Plane Resonant NEM (IP R-NEM) sensor based on a mass-detection principle and discusses its extremely high mass sensitivity in comparison with present-day mass-detection-based biosensors. Our resonator architecture has amplified output signal due to the integrated lateral FET and can be realized by a top-down process on SOI substrates, which is expected to enable monolithic integration of the NEM sensors with CMOS ICs. This project is financially supported by EUFP7 project NEMSIC (Hybrid Nano-Electro-Mechanical/Integrated Circuit Systems for Sensing and Power Managemant Applications).
Primary investigators
- fah07r
- hm2
- Yoshishige Tsuchiya
Partners
- EPFL
- IMEC-BE
- IMEC-NL
- TUDelft
- CEA-LETI
- Honeywell
- Univ. of Geneva
Associated research groups
- Nano Research Group
- Southampton Nanofabrication Centre