Top PDF Data Remanence in Semiconductor Devices

Data Remanence in Semiconductor Devices

Data Remanence in Semiconductor Devices

The best way to avoid short-term retention effects is to ensure that no memory cell holds a data value for more than a certain amount of time. Based on the figures given earlier, a few minutes of storage of a given value should be treated as an upper bound; storage for any larger amount of time will cause detectable effects in the memory cell, although it may take quite a while longer before these effects really become a problem. In a series of tests carried out on a sample of SRAM devices, changes in device threshold voltage, transconductance, and drain-source current were observed after 100–500 seconds of stress, leading to a corresponding change in SRAM access time and operating voltage [44]. As the SRAM cell in Figure 4 indicates, reads and writes of 0 and 1 bits stress different access transistors in the cell so that it’s possible to determine whether a 0 or 1 was stored there by determining which transistor was stressed the most (the grey dots in the figure indicate the main stress locations). The change in cell behaviour can be determined by recording the cell access time, through voltage microprobing of the cell’s transistors, or using some of the other techniques mentioned earlier. Similar tests have been performed on DRAMs, although in this case the emphasis was on stress effects on shared circuitry such as address buffers and sense amplifiers. While there were quite noticeable effects in all of these areas the study didn’t examine the effect on individual storage cells [45].
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Two contact semiconductor devices for ultra fast switching and synchronisation

Two contact semiconductor devices for ultra fast switching and synchronisation

As subscriber demand for existing telecommunication services increases and with the expected uptake of more advanced services, the future telecommunication networks operated by the telecommunications companies worldwide may be required to operate with link capacities > 10 Gb/s and switch capacities ~ 1 Tb/s within a time frame of perhaps -20 years. As the number of subscriber services increases, including the potential for home-working, shopping and entertainment, the networks providing the transport and switching of data services will need careful design. Already the move away from Plesiochronous (PDH) [1.3] towards Synchronous (SDH/Sonet) [1.3, 1.4] networks is prevalent worldwide. BT and other network operators are installing switching equipment capable of synchronous operation. As well as this move towards synchronously switched networks, line capacities are increasing towards 2.5 Gb/s and beyond, with commercial systems at these line rates already being procured in Canada, France, Spain and the USA. In addition, the need to be able to provide flexible bandwidth allocation has been identified with some customers wanting direct access to capacities equal to that presently used in the transport layer (ie. 155 Mb/s). Synchronous networks are of particular interest in this respect due to their flexibility in bandwidth provision using Asynchronous Transfer Mode (ATM) [1.5], which is ideal for multimedia applications up to - 155 Mb/s at present.
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Electron and Ion-beam Characterization of Nitride Semiconductor Devices.

Electron and Ion-beam Characterization of Nitride Semiconductor Devices.

The most comprehensive study of this topic is that of Bartel et al. 119 They claim that their sample preparation procedures eliminate surface roughness variations larger than atomic steps, and thus the thickness artifacts are minimized. At 150kV, they performed a time-resolved experiment and found that instabilities in the microscope and environment can mimic the results noted above 116,117,118 . Analysis of the statistical fluctuations of signal within a single image lead them to note that the standard deviations of measured indium contents within the quantum wells were significantly larger than those observed in the GaN matrix; this indicates that the statistical In-composition deviates from a simple Poisson distribution expected from miscible alloys (i.e., AlGaAs), and indicates that the In-concentration is not homogenous. However, neither is it directly measurable from the data, due to averaging through the foil thickness. This data was compared to 800kV data and found the same trends. They then concluded that reliable In-fluctuation measurements can be obtained from 150kV data, but that microscope or environmental instabilities, as well as sample-preparation surface roughness, can introduce noise as large as the signal itself.
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Data remanence and digital forensic investigation for CUDA Graphics Processing Units

Data remanence and digital forensic investigation for CUDA Graphics Processing Units

Table III shows the results of a GPU reset. This is carried out using the nvidia smi tool available in the CUDA frame- work [10] [20]. This demonstrates that a reset of the GPU will not affect the memory contents on the consumer and server grade devices. The mobile device, however, does not have the ability to reset the GPU alone. These results demonstrate the possibility of data recovery in a forensic investigation when a suspect has attempted to wipe traces of previous activities through resetting the GPU using the built-in commands. These results also demonstrate that legitimate users should not rely on this function to avoid data leaks, or to prevent other users from accessing their data following processing on a shared GPU.
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Development of Zn-IV-Nitride Semiconductor Materials and Devices

Development of Zn-IV-Nitride Semiconductor Materials and Devices

XPS survey scans were taken with a 1eV step-size, 100 ms collection time, 40 eV pass energy, and ‘slot’ aperture. High resolution scans of the valence band region and carbon, oxygen, zinc, tin, and nitrogen peaks were acquired at 25meV step- size, 10eV pass energy, and ‘slot’ aperture. Peaks were analyzed with Casa XPS software using Gaussian-Lorentzian shapes and Shirley baselines. Stoichiometries were calculated with Zn 2p, Sn 3d, N 2s, C 1s, and O 2s peaks. After PES analysis, samples were removed from vacuum and measured with x-ray diffraction (XRD). Patterns from the samples were collected and analyzed using a high-resolution X-ray diffractometer employing Cu Kα radiation (λ = 1.5418 Å). The stoichiometry of the samples was measured using a scanning-electron microscope (SEM) equipped with an energy-dispersive spectrometer (EDS). The dielectric functions were determined by spectroscopic ellipsometry, with the data modeled using a wavelength-by-wavelength layer on top of a substrate layer. Hall measurements were performed to obtain carrier concentrations.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

As seen in Table 2.2, Figure 2.15, and Figure 2.16, the average incremental elastic modulus for collagen and elastin dominant regions increased with increasing culture time for the cellularized samples. We expected to see the same trend with the decellularized samples considering the decellularization process had negligible effect on mechanical response (Figure 2.13). As evidenced by the data below, we saw a decrease in elastin modulus for the decellularized samples between the day 7 and day 12 time points. In all cases, except day 12 decellularized, all the ring-shaped constructs with the same culture time were cultured simultaneously. For example, when the day 7 rings reached the end of their culture time, 5-7 ring specimens were used for cellularized tests, and the rest were subjected to decellularization prior to mechanical testing. For the day 12 samples, the cellularized and decellularized samples were not from the same batch. For this reason, we believe the difference in donor smooth muscle cells was the reason for lack of mechanical integrity in the day 12 decellularized constructs.
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Transient electrothermal simulation of power semiconductor devices

Transient electrothermal simulation of power semiconductor devices

An IGBT model based on semiconductor physics has pro- vided our approach for finding the analytical solution of tran- sient thermal response. The approach of this new IGBT model is to solve the ambipolar diffusion equation (ADE), describ- ing the dynamic charge, with the Fourier-series-based solution method [19], [20]. This method also results in a similar solution as proposed in [21]. The number of nodes required in our method is typically lower than the number of effective time constants (equivalent to nodes) proposed in [21], though the resulting elec- trical equivalent circuit is the same in both thermal models, an equivalent RC-ladder network with associated current sources. Another disadvantage described in [21] is the need to use FEM simulations of heating curves (thermal impedances) to create the necessary model matrix used in the circuit simulations. Our method does not require any simulated or experimental data, but only knowledge of the package system materials and physical dimensions.
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Bayesian Lifetime Modeling for Power Semiconductor Devices

Bayesian Lifetime Modeling for Power Semiconductor Devices

10000) and the percentage of failed tests is the indica- tor for the model quality The comparison of the pre- dicted and the real density of two representative datasets is shown in figure 5. The used model fits the data of test T02 almost perfectly, because only 0.01% of the GoF tests fail. In contrast to this result 100% of the GoF tests fail for test T 15. In total, three posterior predic- tive distributions fit the data well (failed GoF < 3%), two show weaknesses (failed GoF ≈ 35%) and three show poor fitting quality (failed GoF > 87%).

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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

As a significant contribution to my thesis, we have undertaken a project whose goal is to determine how local structure of a network is determined by the degree sequence alone of local samples of the network. In determining this structure, we are interested in those structural properties captured by the Laplacian spectrum of the studied samples. To this end, we have taken four local snowball samples of the network and determined their degree sequence and spectrum. For each sample, we ran a Monte-Carlo Markov chain (MCMC) on the space of graphs with the corresponding degree sequence to produce a large number of random graphs with this corresponding degree sequence. We computed the spectrum of each random graph and then created an empirical probability density function for these spectra to see whether there are any observable localized eigenvalues. Appendix B contains this data, in which one can see the degree sequence and spectrum of each network sample as well as the empirical probability density function for the corresponding MCMC generated spectra.
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Ferroelectric HfO2 for Emerging Ferroelectric Semiconductor Devices

Ferroelectric HfO2 for Emerging Ferroelectric Semiconductor Devices

In this work, a program has been created using MATLAB based on Miller’s [15] and Lue’s [16] models. Their approach uses the switching physics of ferroelectric devices along with the physics of MOSFET, based on Brew’s charge sheet model. The main difference lies in the expression of the polarization. Both models were computed and compared with simulated data from papers as well as with experimental data. A good match was found between experimental and simulated data, with ferroelectric characteristics similar to the one extracted with the TF 1000 analyzer. This program offers a friendly user interface which can be used to simulate ferroelectric films for FeFET applications.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Increasing parent-child communication about sex and contraception is identified as a protective factor that is most amenable to change directly by a teen pregnancy prevention program. The purpose of this study was to explore African American and White 18-19 year old males’ sexual risk communication with their parents during early adolescence and how these experiences affected their attitudes and beliefs about sex and contraception. From June through July 2012, a total of six focus groups (N=30) were conducted. Qualitative coding and analysis revealed themes related to parenting style, males experiences communicating with their parents about sex and contraception, and beliefs and attitudes about sex and contraception. Supporting qualitative data are presented in connection with each theme. This study gained insight about the characteristics and quality of parent-son sexual risk communication from the son’s perspective. Implications for interventions promoting improved parent-child sexual risk communication are discussed.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Landscape ecologists have increasingly turned to the use of landscape graphs in which a landscape is represented as a set of nodes (habitat patches) connected by links representing inter-patch-dispersal. This study explores the use of a novel regionalization method, GraphRECAP (Graph-based REgionalization with Clustering And Partitioning), to detect structural groups of habitat patches (compartments) in a landscape graph such that the connections (i.e. the movement of individual organisms) within the groups are greater than those across groups. Specifically, we mapped compartments using habitat and dispersal data for ring-tailed lemurs (Lemur catta) in an agricultural landscape in southern Madagascar using both GraphRECAP and the widely-used Girvan and Newman method. Model performance was evaluated by comparing compartment characteristics and three measures of network connectivity and traversability: the connection strength of habitat patches in the compartments (modularity), the potential ease of individual organism movements (Harary Index), and the degree of alternative route presence (Alpha Index). Compartments identified by GraphRECAP had stronger within-
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

studio framework. This software package allows for code to be developed in a simulation environment before being applied directly to the hardware. Once the binary file has been compiled from C code, the targeted cores from the DSP system are then connected and the binary file loaded. For any memory needs, such as loading the index data and short reads into memory, a memory browser is used to load directly to the memory architectures available. The selected cores may then be executed to run the loaded binary instructions. In a production environment, the short reads would be able to be transferred through one of the DSP’s many high throughput communication modules available. This system of streaming short reads from the NGS frees up additional memory from the DSP. Unlike alternate coprocessors, the design of the DSP allows for an implementation to entirely run on a self-contained board. The Advantech board used in this thesis requires that power be supplied over a PCI Express connection provided by a computer, but no other functionality is used from that connection. Ideally, testing would be completed with an alternate power source and the board would operate outside of a computer environment, but precise power measurements are still able to be obtained for testing purposes of this thesis.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Baseline and follow-up (Phase II) in-person interviews were conducted with consenting families (n=481 baseline; n=292 follow-up). Baseline interviews were administered 13 months (mean time) following the screening (from 9/03 to 1/06 and follow-up interviews began 20 months later (9/07-2/09). The participating caregiver was often the child’s mother. Interviews (baseline and follow-up) were completed primarily in-person; written questionnaires for parents were sent home in advance of the interview and collected and checked for completeness during the interview. Interviews were conducted via telephone and parent measures returned by mail if families moved away, did not wish to meet at the study interview site or the child’s school, or have interviewers come to their home. Participants were given an incentive (gift cards at baseline or cash at follow-up) for participation in the study. Following each interview, diagnostic data were independently reviewed by a project child psychiatrist. Parents were sent a findings letter, and referral information was provided if findings suggested a probable diagnosis.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

In looking at the literature we see how the passage and implementation of Title IX has affected the gains, academic and social, of females in the United States. Today, more girls are participating in higher level math and science classes and enrolling in higher education. Some authors have classified our current situation as a boy crisis while others say it is simply a matter of girls catching up and competing. We also have seen how the passage of NCLB has enabled the current rush to find better programs to meet the accountability requirements of the federal government. One of these programs, the creation of single gender classrooms, has caused a stir among educational theorists, practitioners, and feminist’s organizations. The proponents of single gender classes have told us that boys and girls learn differently and separating them by gender will accentuate their academic progress by teaching to their gender strengths. Opponents of the single gender program point to the progress made by women since the passage of Title IX, and we should keep the status quo in order to further help women to meet the challenges of the world today. Opponents feel implementing single gender programs will have a harmful effect on future generations and point to the lack of data proving single gender classes provide any enhancement for either gender.
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Prevention of Cold Boot Attacks on Linux Systems

Prevention of Cold Boot Attacks on Linux Systems

Cold - boot attacks can be initiated with the right tools. We have looked at how memory can remain in the physical module due to data remanence flaw in the nature of semiconductor technology. Further by cooling the RAM module the decay rates can be slowed down which enables this side channel attack. Thus data can be retrieved by using a pre execution boot environment tool.

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Micro Data Handling for nm Range Semiconductor Device Using High Resolution ADC

Micro Data Handling for nm Range Semiconductor Device Using High Resolution ADC

The proposed device can be used to measure particular range of resistivity with effect of noise under consideration. The IV characteristic of the device on the Si chip can also be measured effectively. The room temperature also affects the Si devices. The temperature is observed by using temperature sensor. This will increase accuracy of measured value. Higher accuracy in measurement of current can be achieved using 24 bit high precision sigma-delta (∑-∆) ADC. All the measured parameters are displayed using graphical LCD display which leads in simplicity and ease of use. The entire work processes a low cost solution over the existing methods of current measurement.
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Simulating nanoscale semiconductor devices

Simulating nanoscale semiconductor devices

of parallel solver packages. Our implementation of LOCA with our RTD simulator makes use of several other packages in Trilinos, including NOX – the nonlinear solver package, AztecOO – the preconditioned Krylov linear solver package, Anasazi – the eigensolver package, and Epetra – a parallel data structure package. We used a Newton- GMRES algorithm to solve the nonlinear equations, which grouped together the NOX and AztecOO packages, and the Anasazi eigensolver to determine when oscillation onsets. To handle the fine grid simulations, we parallelized the RTD simulator, which involved using the Epetra package.
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Design and Analysis of Multilevel Inverter Topology using less number of Switches

Design and Analysis of Multilevel Inverter Topology using less number of Switches

Multilevel voltage source inverter is recognized as an important alternative to the normal two level voltage source inverter especially in high voltage application. Using multilevel technique, the amplitude of the voltage is increased, stress in the switching devices is reduced and the overall harmonics profile is improved. Among the familiar topologies, the most popular one is cascaded multilevel inverter. It exhibits several attractive features such as simple circuit layout, less components counts, modular in structure and avoid unbalance capacitor voltage problem. However as the number of output level increases, the circuit becomes bulky due to the increase in the number of power devices. In this project, it is proposed to employ a new technique to obtain a multilevel output using less number of power semiconductor switches when compared to ordinary cascaded multilevel inverter.
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Effects of ionizing radiation on nanomaterials and III-V semiconductor devices.

Effects of ionizing radiation on nanomaterials and III-V semiconductor devices.

Devices based on III-V semiconductors and nanomaterials are expected to be critical components of future microsystems as the demand for greater functionality, range of application, and robustness continue to increase. There currently is a need for small-scale power supplies which can be used to power microsystems thereby enabling autonomous functionalities. The use of III-V semiconductor-based solid state devices and nanomaterials to convert the radiant energy of a radioisotope source into electricity has been investigated as a viable option to fulfill this demand. The energy imparted to a material by incident alpha-particles, resulting in electron-hole pair formation and ionization, may be converted into usable electrical power by a radioisotope microbattery (RIMB). A model describing the spatially varying rate of ionizing energy deposited in an absorber material held in close proximity to an isotropic alpha-emitting radioisotope source has been developed. The alpha-particle energy deposition model (ADEP) allows the total energy exciting the RIMB devices to be calculated and thereby provides a means to determine the efficiency of the experimentally measured devices. Two RIMB designs are investigated including a direct conversion microbattery based on a nipi-diode structure and an indirect conversion microbattery employing radioluminescent nanophosphors.
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