Добірка наукової літератури з теми "Electrostatic Discharge Realiability of Electron Devices"

The paper presents the results of a theoretical and experimental study of the deceleration of ion and plasma flows in ion decelerators operating on the basis of an [Formula: see text] discharge with the Hall effect. For quantitative computational analysis of the deceleration process, an analytical model of the electric deceleration layer (E-layer) is proposed; it is based on a diffusion model of a discharge with closed electron drift, in the approximation of classical electron mobility transverse to the magnetic field, taking into account the electron current escape out of the ion beam region. Estimated dependences of the E-layer parameters and the efficiency of ion kinetic energy conversion into electrical energy on the parameters of the incident ion flow are given. The experimental results on the deceleration of plasma and ion flows with the xenon ion energy from 0.15 to 2 keV and ion current density in the range of 1–30 A/m2 are presented. The E-layer properties such as its thickness, the efficiency of the ion kinetic energy conversion into electrical energy, and the layer position in the deceleration channel were determined by test. We studied the effect of partial closure of the electron drift current in the deceleration channel outside the plasma flow volume on the efficiency of energy conversion. The study results can be used to build a detailed phenomenological pattern of plasma flow deceleration in devices with an [Formula: see text] discharge with the Hall effect and to assess the possibility of developing various ion decelerators.

The electrostatic discharge (ESD) reliabilities in different power MOSFETs will be investigated in this paper. From the experimental results, ESD zap pulses at the gate terminal will cause electrons or holes trap in the gate oxide and loss the Si-SiO2 interface integrity, especially for the 100V nDEMOS, 200V nDEMOS, and IRF640, in which they do not have any ESD protection strategy. Electrons or holes trapped in the gate SiO2 layer will be caused the transconductance (Gm) or threshold voltage (Vth) of a MOSFET increasing or reduction, and which is resulted from electron mobility degradation. The RFW2N06RLE and RLD03N06CLE power VDMOS ICs, which with different kinds of ESD protection circuit, are less influenced by ESD pulses experimentally.

This article describes a method of measurement of the current-to-probe voltage characteristic curve of a Langmuir electrostatic probe immersed in a plasma characterized by a low electron temperature that is only one order of magnitude higher than room temperature. These plasmas are widely used in industrial processes related to surface technology, polymers, cleaning, nanostructures, etc. The measurement method complies with the strict requirements to perform representative plasma diagnosis, particularly in the ion saturation zone when the probe is polarized much more negatively that the potential of the plasma bulk surrounding the probe and allows to diagnose the plasma very quickly and locally, making it possible to better monitor and control the plasma discharge uniformity and time drift. The requirements for the Langmuir probe design, the data acquisition and data treatment are thoroughly explained and their influence on the measurement method is also described. Subsequently, the article describes different diagnostic methods of the magnitudes that characterize the plasma, based on theoretical models of that characteristic curve. Each of these methods is applied to different zones of the measured characteristic curve, the obtained results being quite similar, which guarantees the quality of the measurements. The advantages and disadvantages of each method are discussed. A series of measurements of the plasma density for different plasma conditions shows that the method is sensitive enough that the temperature of the ions needs to be taken into account in the data processing. Finally, a Virtual Instrument is included in the LabView environment that performs the diagnosis process with sufficient speed and precision, which allows the scientist to control the parameters that characterize the plasma to increase the quality and performance of the industrial processes in which the plasma diagnosis is to be used. The Virtual Instrument can be downloaded for free from a link that is included, in order to be easily adapted to the usual devices in a plasma laboratory.

The development of novel materials is essential for the next generation of electric vehicles and portable devices. Tin oxide (SnO2), with its relatively high theoretical capacity, has been considered as a promising anode material for applications in energy storage devices. However, the SnO2 anode material suffers from poor conductivity and huge volume expansion during charge/discharge cycles. In this study, we evaluated an approach to control the conductivity and volume change of SnO2 through a controllable and effective method by confining different percentages of SnO2 nanoparticles into carbon nanotubes (CNTs). The binder-free confined SnO2 in CNT composite was deposited via an electrostatic spray deposition technique. The morphology of the synthesized and deposited composite was evaluated by scanning electron microscopy and high-resolution transmission electron spectroscopy. The binder-free 20% confined SnO2 in CNT anode delivered a high reversible capacity of 770.6 mAh g−1. The specific capacity of the anode increased to 1069.7 mAh g−1 after 200 cycles, owing to the electrochemical milling effect. The delivered specific capacity after 200 cycles shows that developed novel anode material is suitable for lithium-ion batteries (LIBs).

One of the main problems for inertial electrostatic confinement devices with electron injection is the space charge neutralization. This work is devoted to the analysis of the problem of plasma quasineutrality in the scheme of plasma oscillatory confinement based on nanosecond vacuum discharge (NVD). Electrodynamics modeling of the processes of aneutronic fusion of proton–boron showed that the plasma in the NVD, and especially on the discharge axis, really corresponds to a quasineutral regime, which is rather different from the well-known scheme of periodically oscillating plasma spheres (POPS). In this case, small oscillations in the NVD are a mechanism of resonant ion heating, unlike coherent compressions in the original POPS model. The scaling of the fusion power turns out to be close to the fusion scheme with POPS, but differs significantly in the values of the parameter of quasineutrality and the compression ratio.

We report the poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP)-based microporous polymer membranes, prepared by phase inversion technique, incorporated with different amounts of nanosized zirconium dioxide (ZrO2) filler. Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and thermal studies confirm the role of ZrO2 nanofiller to modify the polymer structure, pore geometry and crystallinity. The nanofillers interact with the PVdF-HFP chains via surface groups and electrostatic interactions, and their incorporation led to an increase in crystalline content of the membrane and ionic conductivity (when activated with a liquid electrolyte (LE)). A possible mechanism for the increase in crystallinity in the polymer due to interaction with nanofiller particles has also been presented. The optimized membrane has been saturated with an LE sodium perchlorate-ethylene carbonate:propylene carbonate for use as a separator/electrolyte in electrical double-layer capacitor (EDLC). The cells fabricated with the nanofiller-incorporated membrane show better performance in terms of specific electrode capacitance, specific energy and specific power (approximately 76 F g−1, approximately 20.9 Wh kg−1 and 2.62 kW kg−1) than the cells using the membrane devoid of nanofillers (approximately 61 F g−1, approximately 17.3 Wh kg−1 and approximately 3.16 kW kg−1), respectively. The EDLC shows approximately 85% retention in specific capacitance for 10,000 charge–discharge cycles.

Single-electron tunneling transistors (SETs) and boxes (SEBs) exploit the phenomenon of Coulomb blockade to achieve unprecedented charge sensitivities. Single-electron boxes, however, despite their simplicity compared to SETs, have rarely been used for practical applications. The main reason for that is that unlike a SET where the gate voltage controls conductance between the source and the drain, an SEB is a two terminal device that requires either an integrated SET amplifier or high-frequency probing of its complex admittance by means of radio frequency reflectometry (RFR). The signal to noise ratio (SNR) for a SEB is small, due to its much lower admittance compared to a SET and thus matching networks are required for efficient coupling ofSEBs to an RFR setup. To boost the signal strength by a factor of N (due to a random offset charge) SEBs can be connected in parallel to form arrays sharing common gates and sources. The smaller the size of the SEB, the larger the charging energy of a SEB enabling higher operation temperature, and using devices with a small footprint (<0.01 µm2), a large number of devices (>1000) can be assembled into an array occupying just a few square microns. We show that it is possible to design SEB arrays that may compete with an SET in terms of sensitivity. In this, we tested SETs using RF reflectometry in a configuration with no DC through path (“DC-decoupled SET” or DCD SET) along with SEBs connected to the same matching network. The experiment shows that the lack of a path for a DC current makes SEBs and DCD SETs highly electrostatic discharge (ESD) tolerant, a very desirable feature for applications. We perform a detailed analysis of experimental data on SEB arrays of various sizes and compare it with simulations to devise several ways for practical applications of SEB arrays and DCD SETs.

AbstractMagnesium batteries are regarded as promising candidates for energy storage devices owing to their high volumetric capacity. The practical application is hindered, however, by strong electrostatic interactions between Mg2+ and the host lattice and due to the formation of a passivation layer between anode and electrolyte. V2O5 is a typical intercalation compound with a layered crystal structure ((0 0 1) interlayer spacing ~ 11.53 Å), which can act as a good host for the reversible insertion and extraction of multivalent cations. Herein, we have presented an investigation of the effects of S injection on the structure, electrochemical performance and Mg2+ diffusion in V2O5 cathode materials for Mg-ion batteries. The V2O5/S composite structure was investigated using X-ray diffraction, field-emission scanning electron microscope and energy dispersive X-ray spectroscopy. The integrated electrode exhibits an improvement in the electrical and electrochemical properties compared to the V2O5 electrode. The as-prepared V2O5/S composite has an initial discharge capacity of 310 mAh g−1 compared to 160 mAh g−1 for the V2O5 electrode. The V2O5/S composite is a promising cathode material for magnesium-ion battery applications.

Main text : Performance engineering of electrochemical energy-storage devices such as Supercapacitors (SCs) requires updated modelling capable of characterizing their electrical output in unique device geometries. In this work, an Equivalent Electrical Circuit (EEC) is developed to fit the impedance data of MXene/reduced Graphene Oxide (rGO) hybrid fiber-shaped supercapacitors (FSCs) fabricated by wet-spinning [1]. The model is applied for the interpretation of impedance data measured on FSCs using different active materials - rGO and MXene in the case of pseudo-capacitors (Figure - upper right side) and pure carbon in the case of Electrical Double-Layer Capacitors (EDLCs) - and polyvinylalcohol (PVA) gel infiltrated with sulfuric acid as the electrolyte and separator. The FSC charge storage behavior is modelled using a Transmission Line Model (TLM) including a finite Warburg impedance for pseudo-capacitance [2], and a Constant-Phase Element (CPE) for the electrostatic contribution (Figure – upper left side). The high frequency part of the Nyquist plots is characterized by a 45° straight line and the use of a TLM clearly improves the fit quality compared to a Randles circuit usually used for pseudo-capacitor modeling [1,2]. The 45° high frequency line and the difference between the two circuits becomes more visible as the length of the SC yarns increases (Figure – lower left side), which is consistent with the observed increase in internal resistance with fiber length evidenced with the TLM. Finally, the low frequency part of the spectra is correctly modeled by a CPE without any leakage resistance, showing that self-discharge is not a significant issue for the electrostatic contribution, at least in the frequency range tested. The fitting results on all tested devices indicate that the internal resistance of the TLM predominantly corresponds to the electrical resistance of the fiber (Figure – lower right side), i.e. the electron conductive phase of the electrode, instead of the electrolyte ionic resistance in usual SCs [2-4]. [1] N. He, Q. Pan, Y. Liu and W. Gao, "Graphene-Fiber-Based Supercapacitors Favor N-Methyl-2-pyrrolidone/Ethyl Acetate as the Spinning Solvent/Coagulant Combination," ACS Appl. Mater. Interfaces, vol. 9, pp. 24568-24576, 2017. [2] S. Touhami, J. Mainka, J. Dillet, S. Ait Hammou Taleb and O. Lottin, "Transmission Line Impedance Models Considering Oxygen Transport Limitations in Polymer Electrolyte Membrane Fuel Cells," J. Electrochem. Soc., vol. 166, no. 15, pp. F1209-F1217, 2019. [3] L. M. Da Silva, R. Cesar, C. M. Moreira, J. H. Santos, L. G. De Souza, B. Morandi Pires, R. Vicentini, W. Nunes and H. Zanin, "Reviewing the fundamentals of supercapacitors and the difficulties involving the analysis of the electrochemical findings obtained for porous electrode materials," Energy Storage Mater., vol. 27, pp. 555-590, 2020. [4] D. I. Abouelamaiem, G. He, T. P. Neville, D. Patel, S. Ji, R. Wang, I. P. Parkin, A. B. Jorge, M.-M. Titirici, P. R. Shearing and D. J. Brett, "Correlating electrochemical impedance with hierachical structure for porous carbon-based supercapacitors using a truncated transmission line model," Electrochim. Acta, vol. 284, pp. 597-608, 2018. Figure caption: (Left) Experimental impedance spectra measured on rGO/MXene fibers-shaped supercapacitors (FSCs) of different length and fitting curves obtained with the herein developed equivalent electrical circuit (EEC). (Right) Internal resistance of the EEC identified by fitting the spectra on the left side per unit length of the FSCs and electric resistance of the rGO/MXene fibers of the electrodes. Figure 1

First, the electron-phonon interaction model, which has recently been developed by authors for thermal predictions within the silicon devices in micro/nanoscales, is verified through the comparison with the experimental measurement of average temperature rise in the channel region of a silicon-on-insulator (SOI) transistor. The effect of the silicon layer thickness of the SOI transistor on phonon thermal characteristics is also investigated. It is found that the thickness effect on the peak temperature of the optical phonon mode in the hot spot region is negligible due to its very low group velocity. Thus the acoustic phonons in a specific frequency band, which has the highest scattering rate with the optical phonons, experience relatively less reduction in the peak temperature as the silicon layer thickness increases. Second, the electron-phonon interaction model is applied to the transient thermal transport simulation during the electrostatic discharge (ESD) event in an n-type metal-oxide-semiconductor (NMOS) transistor. The evolution of the peak temperature in the hot spot region during the ESD event is simulated and compared with that obtained by the previous full phonon dispersion model, which treats the electron-phonon scattering as a volumetric heat source. The results show that the lower group velocity acoustic phonon modes (i.e., higher frequency) and optical mode of negligible group velocity acquire high energy density from electrons during the ESD event, which might cause the devices melting problem. The heat transfer rates by individual phonon modes are also examined, and it is found that the key parameter to determine the phonon heat transfer rate during the ESD event is the product of the phonon specific heat and the scattering rates with higher energy density phonons in the hot spot region.

Electrostatic Discharge (ESD) reliability is one of the major reliability concerns in integrated circuits (IC), which if not addressed while designing devices and circuits, can lead to a permanent damage to the Integrated Circuits. The same becomes a rather more stringent in case of system level ESD events (System level ESD), which usually occurs in uncontrolled or harsh environments. To address these issues physical insights into the non-equilibrium electron-phonon (electro-thermal) behaviour of these devices, under nano-second time scale high-current conditions, are required to be developed. These insights are subsequently used to develop reliability aware device. Keeping this larger problem in mind, in this work, we focus on developing physical insights into ESD behaviour of advanced high voltage CMOS/BiCMOS & beyond CMOS device options. Using the physical insights developed, this work also demonstrates using computations and experiment’s reliability aware device design. The thesis/work is divided into following threads: In the first part of this work, insights into various system level ESD problems in advanced High Voltage CMOS devices is developed. High voltage functionalities are the key for building system on chips (SoC) in mobile and automotive products. However, high voltage LDMOS/DeNMOS devices are prone to early ESD induced damages with charge modulation induced current _laments. To withstand extremely high current levels ( 30 A), during system level ESD events, in lowest possible area footprint, Silicon Controlled Rectifier (SCR) solutions are preferred. SCR can switch from a high voltage blocking state to an ohmic state and conduct high current levels. However, implementing SCR in High voltage LDMOS/DeNMOS technologies presents different challenges. First part of the thesis focuses on three of such major challenges i.e. Power scalability, Window failures when stressed through Common Mode Choke (CMC) and Air discharge failures. Furthermore, HBM and CDM qualified HV-SCR devices have found to cause early failures during system level stress conditions. System level discharges can last longer than HBM & CDM time scales (100ns), SCR should survive for pulse widths > 100ns. In this thesis, a unique low current ESD failures in LDMOS based SCRs during snapback is reported for the first time. Failure is universal to LDMOS-SCR devices designed as an efficient MOS switch and found to be specific to a window of current between trigger and holding state and can only be captured using high resistance load-line in Transmission Line Pulse (TLP) test system. This resulted in severe power scalability issues in LDMOS-SCRs for longer stress durations (Pulse width>100 ns). While using systematic experiments and 3D Technology Computer Aided Design (TCAD) simulations, we have developed detailed physical insights into the low current ESD failure phenomenon in LDMOS-SCR devices. Physical insights developed has resulted in design solutions to avoid low current failure and mitigate power scalability issue without interfering with functional operation and MOS performance. Further, the severity of the power scalability problem with increasing LDMOS voltage classes (from 40V Design to 80V LDMOS) is highlighted with a need for novel design strategies. A systematic design approach is presented to evaluate the effect of different design parameters on LDMOS _lament and SCR turn-on near the snapback region. New design guidelines are presented to improve the power scalability without compromising on its ON-state DC (functional) and Safe Operating Area (SOA) characteristics. On the other hand, signalling at certain high voltage I/Os can go below ground levels. Hence, Bidirectional SCR (BDSCR) protection elements are needed to block high voltage under different stress polarities. Power Scalability of High Voltage BDSCR for long duration pulse discharges (PW >100 ns), is also studied in this thesis. Power scalability trends are found to be sensitive to the Transmission Line Pulse (TLP) measurement set-up. Detailed physical insights into the early formation of current filaments along with filament motion in BDSCR is presented in detail using 3D TCAD. Dynamic current filament motion in Bi-directional high voltage SCRs is found. Back and forth current filament motion is found to improve the power scalability trends in BDSCR devices for long stress durations. Finally, impact of silicide blocking in mitigating filament strength has been studied, which in turn improves the ESD robustness and overall power scalability. The device design and physical understanding from investigations in helped to come-up with a new approach to engineer LDMOS drivers for safe snapback. Proposed method considers engineering both static filament & Dynamic/Moving current filaments in LDMOS design. Dynamic filament motion and its relation to NPN turn-on engineering is studied. A unique window failure in LDMOS near snap-back discussed for the first time in LDMOS designs. The presented approach resulted in 10-time improvement in ESD robustness for self-protecting concepts. Finally, different fundamental questions related to origin of filament motion are explored with the help of engineered LDMOS Designs. Another major challenge in development of HVSCR is, its survival against system level ESD stress through Common Mode Choke (CMC). Some of the communication pins (CAN) in automotive ICs need to pass system level IEC test through choke. CMC is an on-chip component present in ESD stress path. A unique failure mechanism for system level ESD stress through a CM choke is investigated. Presence of choke in stress path is found to change current waveform shape that ESD protection devices experience on-chip. Minor variations in the stress current waveform shape for specific IEC stress levels are found to cause an unexpected window failure in Drain Extended NMOS SCRs (DeNMOS-SCR). 3D TCAD simulations are used to understand the device behaviour and failure under the peculiar two-pulse shaped IEC current waveform. A novel DeNMOS-SCR design is demonstrated to increases ESD robustness against the peculiar two pulse stimulus and to avoid system level ESD failures. Air discharge failure in HV-SCRs is another major bottleneck in developing on- chip system level protections. High voltage BDSCR devices are found to be vulnerable to system level air discharge failures. The failure observed is sporadic in nature and found to be function of pulse rise time. Root cause for such SCR failure sensitivity to specific rise times is studied in detail using Multi-Finger 3D TCAD Simulations. A novel design solution is prosed to improve BDSCR robustness against the air discharge failures. Second part of the thesis focuses on understanding ESD device physics of new transistor concepts such as Tunnel FETs and graphene-based FETs. Current as well as the time evolution of the junction breakdown, device turn-ON, voltage snapback, and finally the failure mechanism is studied using both 2-D and 3-D TCAD simulations In Tunnel FETs. The interaction between the band-to-band tunnelling, avalanche multiplication, and thermal carrier generation leading to voltage snapback and failure is presented in detail, along with the electro-thermal instability initiated _lamentation. Impact of various technology and device design parameters on the ESD behavior and robustness of TFETs is discussed. The obtained details will be useful in designing ESD protection concepts in future TFET technologies. Experimental ESD studies on Graphene FETs using matured technology platform are carried out to study the impact of diffusive vs. ballistic carrier transport and top-gate vs. back-gate on failure mechanisms. Insights on current saturation in graphene FET in ESD time scales and a novel step by step failure in dielectric capped transistors is presented. Finally, influence of various top-gate designs on the ESD performance is reported. Safe Operating area boundary definitions in Graphene FETs is also explored. Obtained insights on device failures in these budding technologies, will help in building stronger ESD protection concepts in graphene-based technologies.