Charge coupled devices

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Analysis of Charge-Coupled Devices Image Sensors with an Overflow Drain Structure

Analysis of Charge-Coupled Devices Image Sensors with an Overflow Drain Structure

In the particular solution, (one-dimensional cas), the PD, TG and the V-CCD electrode potentials are assumed zero, n-substrate is assumed equipotential (equal to Vs). the potential and electric field are continuous through the the boundary of the different layer. In the homogenous solution, the PD is at VPD, the TG and V-CCD is at Vh which is the electrode potential at charge transfer moment. n-substrate is assumed equipotential (equal to Vs).The 2PW is grounded from the right hand. of the cell. In the channel stop, a simple interpolation between the PD potential and the electrode potential is done, assuming a uniform variation. Periodicity is assumed a long the left hand side and the right hand side of the cell except the 2PW which is grounded.
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An investigation into the use of charge-coupled devices for digital mammography

An investigation into the use of charge-coupled devices for digital mammography

The technique of dithering was introduced in 3.4.3. to dynamically reduce the dark current. This was necessary because it is not possible to fully invert all phases of a conventional CCD, as this would result in the potential wells beneath each phase being equivalent and there being no collecting well. More recent CCD designs, including newer 15-1 Is and their replacement, the 30-1 Is, are available which overcome this limitation. These chips, known as multi pinned-phase (MPP) CCDs can operate totally inverted to achieve ultra-low dark current generation rates. For a three phase CCD this is achieved, for example, by doping the silicon beneath phase three such that when all phases are biased into inversion charge will collect under phases one and two, and be confined by phase three, known as the barrier phase. The full well capacity of a MPP CCD is determined by the MPP built in potential and, depending on pixel size, may be as much as 2-3 times lower than when only 1 or 2 of the three phases are inverted (Janesick 1991). EE Vs data sheet for the CCD30-11 gives the typical maximum peak charge storage as 500k electrons per pixel, compared with 750k for the 15-1 Is used here. This reduction in full well capacity means that MPP CCDs are not suitable for all x-ray examinations, for which the above techniques should be used.
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Bistability in the Electric Current through a Quantum-Dot Capacitively Coupled to a Charge-Qubit

Bistability in the Electric Current through a Quantum-Dot Capacitively Coupled to a Charge-Qubit

A spin-degenerate single-level quantum-dot(QD) which is tunnel coupled to two metallic electrodes is the simplest model for studying electronic transport through nanostructures. The response of this model system to the external fields depends on the internal properties of the QD. In the realistic situations, such interactions like electron-electron, electron-phonon or spin-orbit interactions result in some novel static and dynamic behaviours in the system which have been the subject of many theoretical and experimental studies in the last three decades [1–15]. The most supportive motivation behind these efforts is the advancement in the engineering and fabrication of nano-scale electronic devices which could affect broad fields of interests like
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Cybersecurity vulnerabilities in medical devices: a complex environment and multifaceted problem

Cybersecurity vulnerabilities in medical devices: a complex environment and multifaceted problem

Abstract: The increased connectivity to existing computer networks has exposed medical devices to cybersecurity vulnerabilities from which they were previously shielded. For the prevention of cybersecurity incidents, it is important to recognize the complexity of the opera- tional environment as well as to catalog the technical vulnerabilities. Cybersecurity protection is not just a technical issue; it is a richer and more intricate problem to solve. A review of the factors that contribute to such a potentially insecure environment, together with the identification of the vulnerabilities, is important for understanding why these vulnerabilities persist and what the solution space should look like. This multifaceted problem must be viewed from a systemic perspective if adequate protection is to be put in place and patient safety concerns addressed. This requires technical controls, governance, resilience measures, consolidated reporting, con- text expertise, regulation, and standards. It is evident that a coordinated, proactive approach to address this complex challenge is essential. In the interim, patient safety is under threat. Keywords: cybersecurity, security, safety, wireless, risk, medical devices
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Charge-Coupled Device Based on an Optical Tomography System for Monitoring Multiphase Flow

Charge-Coupled Device Based on an Optical Tomography System for Monitoring Multiphase Flow

Flexible rod was used to control the light distance manually. Light expansion system consists of laser diode with attached lens and covered by a thin frosted plastic (table tennis ball). Laser fan beam projection will pass through the square aperture and this square laser light Abstract: Tomography is a method to capture a cross-sectional image based on the data obtained by sensors, distributed around the periphery of the analyzed system. Optical tomography is one of the tomography methods which are non-invasive and non-intrusive system, consisting of emitter with detectors. Combinations of Charge- Coupled Device and low intensity laser diode are used in this research. Experiments on air bubbles detecting in non-flowing crystal clear water are conducted. Cross-sectional image of two phase flow; air and liquid are captured using this optical hardware construction and the information on air diameter, shape and path are observed using LabVIEW programming.
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A charge coupled device based optical tomographic instrumentation system for particle sizing

A charge coupled device based optical tomographic instrumentation system for particle sizing

The existing system uses low power laser diodes and the laser diode needs to be illuminated for 6 milliseconds in a single projection system. Using a higher power of laser will reduce the illumination time. This will have several advantages - it will improve signal to noise ratios, because CCD devices can leak charge between sensors. This leakage increases with time. Reduced leakage will improve image contrast. A short pulse of illumination is required if the system is used in monitoring dynamic behaviour of the particle, as the system measurement needs to be fast to prevent image blur.
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Privacy Preserving Aggregate Statistics for Mobile Crowdsensing

Privacy Preserving Aggregate Statistics for Mobile Crowdsensing

computational and communication performance of mobile devices, coupled with the advances in sensor technology, leads to an exponential growth in data collection and sharing by smartphones.Exploiting quality of such an oversized volume of potential users, a new mechanism for efficient and scalable data collection has emerged, namely, spatial crowdsourcing (SC).SC has various applications in domains like environmental sensing, smart cities, journalism, and crisis response.With SC, requesters and employees usually register with a crowdsourcing server that acts as a broker between parties, and infrequently conjointly plays a job in however tasks ar appointed to employees.A requester issues one or more tasks to the server (i.e., the platform). The server then assigns the task to a worker.
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Quantum capacitance and charge sensing of a superconducting double dot

Quantum capacitance and charge sensing of a superconducting double dot

The ability to make small capacitance devices in which the electrostatic energy per elec- tron is larger than the thermal energy has allowed a family of ‘single electron devices’ to be made and investigated, including single electron transistors (SETs), semiconductor dou- ble quantum dots, and superconducting SETs. By using capacitively coupled gate voltages to manipulate the charge occupancy, they have been exploited as, amongst other things, charge sensors 1–3 , probes of chemical potential 4 , charge qubits 5,6 and spin qubits 7 . The key

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Tunneling in Systems of Coupled Dopant Atoms in Silicon Nano devices

Tunneling in Systems of Coupled Dopant Atoms in Silicon Nano devices

We first show how individual or coupled dopants modulate the potential landscape in the channel of silicon nano-devices. For that purpose, we describe results ob- tained using a specially designed Kelvin probe force mi- croscopy (KPFM) technique [20]. We then show how dopant atoms or clusters of strongly-coupled dopants control the quantum-tunneling conductance in nanoscale transistors doped in different regimes of doping con- centration. In that sense, we analyze low-temperature electrical characteristics that exhibit signatures of single- electron tunneling (SET) mediated by dopant-induced quantum dots (QDs) [19]. Depending on the internal structure of the QD, i.e., number and interaction strength among dopants forming the QD, the current peaks exhibit distinct properties, illustrating electron transport via either atomic- or molecular-like structures.
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Investigation of induced charge damage on self-aligned metal-gate MOS devices

Investigation of induced charge damage on self-aligned metal-gate MOS devices

The nitride thin films can be characterized by both chemical as well as physical properties. Chemical properties such as the Si/N ratio or Si-H and N-H concentrations can affect etch rates, band gap and permittivity. Silicon rich nitride films exhibit better interface quality but higher permittivity and leakage. Nitrogen rich films show lower permittivity and leakage, but a less desirable interface with more stress. With excess nitrogen, density of interface states at mid-gap increases resulting in mobility degradation [9]. Increased nitrogen content has, however, been found to increase the band gap as high as 5eV and decrease deposition rates [10]. Elevated hydrogen content increases etch rate (good for tight critical dimension control), and passivates dangling bonds in the bulk as well as at the interface. On the downside, excess hydrogen results in Si- H bonds which lead to charge trapping when Si3N4 is used as the gate dielectric [9]. For this case, N-H bonds are preferred over Si-H. Using a low temperature (~180C) and SiH4/N2 gas flow, a very low hydrogen content in the form of Si-H can be achieved [10].
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Increase of charge carrier redistribution efficiency in a laterally organized superlattice of coupled quantum dots

Increase of charge carrier redistribution efficiency in a laterally organized superlattice of coupled quantum dots

QDs have a large areal overlap that laterally close QDs do not. On the other hand, we are not considering just two dots, but a semi-infinite plane of 共laterally organized兲 dots, which restores the symmetry, and eventually leads to miniband ef- fects. A second difference between vertically and laterally coupled QDs is the tunneling barrier. In vertically coupled QDs, the barrier through which tunneling must occur is the matrix material, whose conduction-band edge lies at energies substantially above those of the dot states. Here, we are not arguing that the dots couple through the matrix, but through the WL, which is made of the same material as the QDs themselves, and has the same conduction-band edge. Thus, we are not considering tunneling of states, which have a lower energy than the conduction-band edge of the ‘‘barrier’’ material, as in vertically coupled dots, but tunneling at ener- gies that are lower energy than those of isolated WL states, but still lie well above the conduction-band edge. A third and crucial difference is that here we are not discussing the cou- pling of the ground state, but of the excited states, whose lateral extent is typically between 1.5 and 2 times that of the ground state, 20,30 and was recently calculated to be about
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Analytical model for the photocurrent voltage characteristics of bilayer MEH PPV/TiO2 photovoltaic devices

Analytical model for the photocurrent voltage characteristics of bilayer MEH PPV/TiO2 photovoltaic devices

interactions [20], on the interfacial charge separation and recombination at the organic/organic interfaces. The quantitative analysis of the charge transfer mechan- ism at the organic/inorganic interfaces in the polymer- based PV cells has been scarcely explored so far. Com- monly, the photoinduced interfacial charge transfer from the polymers to inorganic semiconductors is explained by the exciton dissociation at the D/A inter- face due to the favorable energy match between the D and A components, without considering the role of the interfacial electric field [16,27-31]. Breeze et al [5] pro- posed an analytical expression including the interfacial electric field for the exciton dissociation efficiency in bilayer MEH-PPV/TiO 2 photovoltaic device, which only
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The effect of interfacial charge on the development of wafer bonded silicon on silicon carbide power devices

The effect of interfacial charge on the development of wafer bonded silicon on silicon carbide power devices

places, features such as those seen in Figure 5 (bottom) are seen, where these are presumed to be pits or voids. This inhomogeneous interface is likely the source of significant charge trapped at the interface. This has been shown in [7] at the Ge/SiC heterojunction to cause Fermi-level pinning, and hence a conduction band offset very different from that expected. Here, it is expected that a high density of interfacial charge causes band bending, which in such a thin, lightly doped Si layer inverts the doping polarity of the entire layer resulting in the p-type behaviour witnessed.
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01 Electric Force.pptx

01 Electric Force.pptx

Laboratory devices used to study the existence of two kinds of electric charge.... Two Negative Charges Repel.[r]

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A Solar Powered Water Pumping Systems in Agriculture

A Solar Powered Water Pumping Systems in Agriculture

Battery-coupled water pumping systems include photovoltaic (PV) panels, charge manage regulator, batteries, pump controller, stress switch and tank and DC water pump (discern three). The electric present day produced by means of PV panels all through daylight charges the batteries and the batteries in flip supply electricity to the pump anytime water is wanted. The use of batteries spreads the pumping over a longer time frame by using supplying a constant working voltage to the DC motor of the pump. Accordingly, throughout the night and occasional mild periods, the machine can nevertheless supply a regular source of water for livestock. The usage of batteries has its drawbacks. First, batteries can lessen the performance of the overall gadget because the running voltage is dictated by way of the batteries and now not the PV panels. Depending on their temperature and the way nicely the batteries are charged, the voltage provided through the batteries may be one to 4 volts decrease than the voltage produced by using the panels in the course of maximum sunlight conditions. This decreased efficiency may be minimized with the usage of the proper pump controller that boosts the battery voltage furnished to the pump.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

electrode depletes the electrons in the channel under the gate as shown in the Fig 1.6 (d), the signal path is cut off and device is said to be in the OFF state behaving as a capacitor. In order to reduce the gate leakage current in conventional Schottky gate HFET various insulated gate technologies have been demonstrated such as metal oxide semiconductor (MOSHFET) [19][20], metal insulator semiconductor junctions (MISHFET) [21] etc. Typically value of threshold voltage is from -4 V for HFET and -8 V for MOSHFET. When used as RF switches, the devices insertion loss is determined by the channel resistance and the two contact resistances whereas the isolation in OFF state is determined by the capacitance. Therefore in order to improve switch performance the product of both R ON *C OFF should be minimum. R ON can be reduced by improving growth
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Environment Monitoring System using Raspberry Pi

Environment Monitoring System using Raspberry Pi

Abstract - The development in embedded system has proved to a reliable solution in monitoring and controlling the environment monitoring system. The project aims at building a system which can be used on universally at any scale to monitor the parameters in a given environment. With the evolution of miniaturized sensor devices coupled with wireless technologies it is possible to remotely monitor the parameters such as temperature, humidity, amount ofco2 in air and many more .We will be using raspberry-pi as our main board and sensors will collect all the real time data from environment and this real time data will be fetched by the web server and display it. User can access this data from anywhere through Internet. Due to unnatural and unpredictable weather farmers now a day face large financial losses due to wrong prediction of weather and incorrect irrigation methods and the amount of pesticides and insecticides used for crops. This system will prove to bean important part in development in agricultural field.
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Fiber coupled nanophotonic devices for nonlinear optics and cavity QED

Fiber coupled nanophotonic devices for nonlinear optics and cavity QED

From afar, fabrication of nanoscale optical components can appear to be predominantly mo- tivated by the same forces that have driven developments in the microelectronics industry, where we have become accustomed to equating smaller with more powerful. Unsurpris- ingly, to a large degree this intuition is correct. Optical chips containing dense arrays of devices have the potential for high bandwidth data processing, and already play a role in the telecommunications industry [1, 2, 3]. However, as a scientist, the motivation for minitur- ization can come from elsewhere: the desire to study optical effects that cannot be observed easily, if at all, without the help of wavelength scale confinement of light. Reassuringly, these two views of optical miniturization are not in conflict. Instead, these interests drive each other: Novel chip-scale optical phenomena often find applications in practical devices, and the usefulness of a scalable, integrated optical platform is not lost on physicists wanting to study increasingly complex systems.
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Diffusion-Driven Charge Transport in Light Emitting Devices

Diffusion-Driven Charge Transport in Light Emitting Devices

While the diffusion injected buried MQW LED described in the previous chapter was the first experimental demonstration of a DDCT-based LED, it had very little novel device functionality. The further development of DDCT-based devices had a double motivation. On the one hand, the goal was to eliminate all parallel non-diffusion based current paths, and on the other hand to demonstrate the novel possibilities enabled by the DDCT-structure. The current diffusion-driven charge transport model can be applied to solve design challenges related to emitters based on near surface quantum wells, surface NWs, QDs, and layered 2D emitting materials, which are hard-to-reach with conventional DHJ structures. With help of DDCT, such emitters can be excited electrically through the bottom contact only with no need for top contacts. This will allow integration of nano-scale surface light emitters in applications which are impossible to realize with DHJ. Moreover, a device with a surface AR leaves out all other electrical excitation mechanisms except bipolar diffusion through only one side of the AR.
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