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Статті в журналах з теми "Hot Carriers Injection":
1
Khurgin, Jacob B. "Fundamental limits of hot carrier injection from metal in nanoplasmonics." Nanophotonics 9, no. 2 (February 25, 2020): 453–71. http://dx.doi.org/10.1515/nanoph-2019-0396.
Анотація:
AbstractThe evolution of non-equilibrium carriers excited in the process of decay of surface plasmon polaritons (SPPs) in metal is described for each step – from the generation of carriers to their extraction from the metal. The relative importance of various carrier-generating mechanisms is discussed. It is shown that both the generation of carriers and their decay are inherently quantum processes as, for realistic illumination conditions, no more than a single SPP per nanoparticle exists at a given time. As a result, the distribution of non-equilibrium carriers cannot be described by a single temperature. It is also shown that the originally excited carriers that have not undergone a single electron-electron scattering event are practically the only ones that contribute to the injection. The role of momentum conservation in carrier extraction is discussed, and it is shown that, if all the momentum conservation rules are relaxed, it is the density of states in the semiconductor/dielectric that determines the ultimate injection efficiency. A set of recommendations aimed at improving the efficiency of plasmonic-assisted photodetection and (to a lesser degree) photocatalysis is made in the end.
2
Zhu, Lang, Zongpeng Song, Ran Li, and Haiou Zhu. "Hot carrier dynamics in MoS2/WS2 heterostructure." Nanotechnology 33, no. 19 (February 15, 2022): 195701. http://dx.doi.org/10.1088/1361-6528/ac4e41.
Анотація:
Abstract TMDs based heterostructure have drawn much attention for its potential application in photoelectric devices benefiting from the rapid and effective carrier separation and ultra-long interlayer exciton lifetime. Recent studies on carrier dynamics of TMDs based heterostructures are mainly focused on the transfer process of photo-generated carriers across the interface and lifetime of interlayer exciton but little attention is paid on the dynamics of hot carriers. Here, the carrier dynamics of hot carriers in MoS2/WS2 heterostructure is investigated by transient absorption spectra. Rapid separation of electron and hole is observed. More importantly, hot carriers of C exciton, which contribute to the absorption of most of the visible light, could compensate for the carrier loss in the band edge exciton energy band through the intervalley transfer process. This re-injection process of hot carriers of C exciton could compensate for carrier depletion in photoelectric devices, thus may greatly improve the light utilization in optoelectronic devices.
3
Marrakh, R., and A. Bouhdada. "Modeling of the I–V Characteristics for LDD-nMOSFETs in Relation with Defects Induced by Hot-Carrier Injection." Active and Passive Electronic Components 26, no. 4 (2003): 197–204. http://dx.doi.org/10.1080/08827510310001624363.
Анотація:
The hot-carrier injection is observed increasingly to degrade the I–V characteristics with the scaling of MOS transistors. For the lightly doped drain MOS transistor the injection of the hot-carriers, caused by the high electric field in the MOS structure, is localized in the LDD region. The modeling of the drain current in relation to defects due to the hot-carrier injection allows us to investigate the I–V characteristics and the transconductance of devices. Consequently, we can know the amount of the device degradation caused by these defects in order to find technological solutions to optimize reliability.
4
BHATTACHARYA, PALLAB. "TUNNEL INJECTION LASERS." International Journal of High Speed Electronics and Systems 09, no. 04 (December 1998): 847–66. http://dx.doi.org/10.1142/s0129156498000361.
Анотація:
Carrier heating in conventional quantum well lasers can lead to several deleterious effects and are related to the transport and thermalization characteristics of injected carriers. The properties of a quantum well laser in which the electrons are directly transported to the lasing subband by tunneling is described here. The resulting device — a tunnel injection laser — is shown to have negligible gain compression, superior high-temperature performance, lower Auger recombination and wavelength chirp, and better high frequency modulation characteristics when compared to conventional lasers. All these improvements are attributed to the reduction of hot-carrier population in the active region of the laser. Results are presented here for lasers made with GaAs — and InP — based heterostructure systems.
5
Liu, Tingting, Cheng Zhang, and Xiaofeng Li. "Strain engineering for enhanced hot-carrier photodetection." Journal of Applied Physics 132, no. 6 (August 14, 2022): 064901. http://dx.doi.org/10.1063/5.0099544.
Анотація:
Hot-carrier devices in metal–semiconductor junctions have attracted considerable attention but still with quantum efficiencies far from expectations. Introducing the lattice strain to the material can effectively modulate the electronic structure, providing a way to control the hot-carrier dynamics. Here, we study how this strain affects the generation, transport, and injection of hot carriers in gold (Au) by using first-principles calculations and evaluate the overall responses of Au-based hot-carrier devices by Monte Carlo simulation. We find that the compressive strain can significantly increase the hot-electron generation from direct transition at E > 1.1 eV for Au. The compressive strain delocalizes the band structure and decreases the electron density of state, which, in turn, reduce electron–electron and electron–phonon scatterings to improve the transport of hot carriers. Taking the Au/TiO2 device as an example, we find that the compressive strain (−6%) can enable a 1.5- to 3-fold enhancement of quantum efficiency and responsivity at a photon energy between 1.2 and 3 eV.
6
Wang, Yunxiang, Buyun Chen, Deming Meng, Boxiang Song, Zerui Liu, Pan Hu, Hao Yang, et al. "Hot Electron-Driven Photocatalysis Using Sub-5 nm Gap Plasmonic Nanofinger Arrays." Nanomaterials 12, no. 21 (October 24, 2022): 3730. http://dx.doi.org/10.3390/nano12213730.
Анотація:
Semiconductor photocatalysis has received increasing attention because of its potential to address problems related to the energy crisis and environmental issues. However, conventional semiconductor photocatalysts, such as TiO2 and ZnO, can only be activated by ultraviolet light due to their wide band gap. To extend the light absorption into the visible range, the localized surface plasmon resonance (LSPR) effect of noble metal nanoparticles (NPs) has been widely used. Noble metal NPs can couple incident visible light energy to strong LSPR, and the nonradiative decay of LSPR generates nonthermal hot carriers that can be injected into adjacent semiconductor material to enhance its photocatalytic activity. Here we demonstrate that nanoimprint-defined gap plasmonic nanofinger arrays can function as visible light-driven plasmonic photocatalysts. The sub-5 nm gaps between pairs of collapsed nanofingers can support ultra-strong plasmon resonance and thus boost the population of hot carriers. The semiconductor material is exactly placed at the hot spots, providing an efficient pathway for hot carrier injection from plasmonic metal to catalytic materials. This nanostructure thus exhibits high plasmon-enhanced photocatalytic activity under visible light. The hot carrier injection mechanism of this platform was systematically investigated. The plasmonic enhancement factor was calculated using the finite-difference time-domain (FDTD) method and was consistent with the measured improvement of the photocatalytic activity. This platform, benefiting from the precise controllable geometry, provides a deeper understanding of the mechanism of plasmonic photocatalysis.
7
Jang, Taejin, Myung-Hyun Baek, Suhyeon Kim, Sungmin Hwang, Jeesoo Chang, Kyung Kyu Min, Kyungchul Park, and Byung-Gook Park. "Analysis of a Schottky Barrier MOSFET for Synaptic Device Using Hot Carrier Injection." Journal of Nanoscience and Nanotechnology 20, no. 11 (November 1, 2020): 6592–95. http://dx.doi.org/10.1166/jnn.2020.18766.
Анотація:
In this paper, we analyze the hot carrier injection (HCI) in an asymmetric dual-gate structure with a metallic source/drain. We propose a program/erase scheme where HCI occurs on the source side of the body. Owing to the large resistance of the Schottky barrier used, a large electric field is formed around the Schottky barrier. Therefore, impact ionization occurs as the gate voltage is increased and hot carriers are injected into the source side, which is less influenced by the drain voltage. We also analyze the program and erase efficiency by adjusting the Schottky barrier height or by using dopant segregation technique. We expect a small amount of current to flow and great efficiency of the program/erase operations to use as a synaptic device.
8
Belenky, G. L., A. Kastalsky, S. Luryi, P. A. Garbinski, A. Y. Cho, and D. L. Sivco. "Measurement of the effective temperature of majority carriers under injection of hot minority carriers in heterostructures." Applied Physics Letters 64, no. 17 (April 25, 1994): 2247–49. http://dx.doi.org/10.1063/1.111659.
9
Wang, Yimin, Yun Li, Yanbin Yang, and Wenchao Chen. "Hot Carrier Injection Reliability in Nanoscale Field Effect Transistors: Modeling and Simulation Methods." Electronics 11, no. 21 (November 4, 2022): 3601. http://dx.doi.org/10.3390/electronics11213601.
Анотація:
Hot carrier injection (HCI) can generate interface traps or oxide traps mainly by dissociating the Si-H or Si-O bond, thus affecting device performances such as threshold voltage and saturation current. It is one of the most significant reliability issues for devices and circuits. Particularly, the increase in heat generation per unit volume due to high integration density of advanced integrated circuits leads to a severe self-heating effect (SHE) of nanoscale field effect transistors (FETs), and low thermal conductivity of materials in nanoscale FETs further aggravates the SHE. High temperature improves the HCI reliability in the conventional MOSFET with long channels in which the energy of carriers can be relaxed. However, high temperature due to severe SHE deteriorates HCI reliability in nanoscale FETs, which is a big concern in device and circuit design. In this paper, the modeling and simulation methods of HCI in FETs are reviewed. Particularly, some recently proposed HCI models with consideration of the SHE are reviewed and discussed in detail.
10
Li, Mengyao, Yating Zhang, Xin Tang, Jitao Li, Silei Wang, Tengteng Li, Hongliang Zhao, Qingyan Li, Qi Wang, and Jianquan Yao. "Improving performance of hybrid perovskite/graphene-based photodetector via hot carriers injection." Journal of Alloys and Compounds 895 (February 2022): 162496. http://dx.doi.org/10.1016/j.jallcom.2021.162496.
Дисертації з теми "Hot Carriers Injection":
1
Zaka, Alban. "Carrier injection and degradation mechanisms in advanced NOR Flash memories." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENT118/document.
2
Tran, Thi-Phuong-Yen. "CMOS 180 nm Compact Modeling Including Ageing Laws for Harsh Environment." Thesis, Bordeaux, 2022. http://www.theses.fr/2022BORD0185.
Анотація:
Au cours des dernières décennies, la demande de fonctionnalités complexes et d'intégration haute densité pour les Circuits Intégrés (CI) a mené à une réduction de la taille des dispositifs métal-oxyde-silicium (MOS). Dans ce scénario, les problèmes de fiabilité sont les préoccupations considérables par suite de la miniaturisation de l'appareil, telles que Hot Carrier Injection (HCI) et Bias Temperature Instability (BTI) qui ont un impact sérieux sur les performances de l'appareil. Dans certains domaines d'application où le coût des pannes est extrêmement élevé, comme l'espace, les champs pétrolifères ou les soins de santé, l'appareil doit pouvoir fonctionner de manière stable et fiable, en particulier dans une plage de températures étendue. Bien que les mécanismes de défaillance des dispositifs aient été intensivement étudiés dans le passé, les investigations de ces mécanismes à hautes températures sont rarement étudiées.L'objectif de cette thèse est de développer les lois de vieillissement de la technologie CMOS 0.18µm afin d'optimiser la conception des circuits pour une durée de vie ciblée sous des températures extrêmes. Nous avons mené une campagne intensive de tests de vieillissement pour nMOS et pMOS avec plusieurs longueurs de grille. Les mécanismes HCI et BTI intrinsèques ont été caractérisés et modélisés sous des tensions de polarisation de fonctionnement typique pour éviter le risque de sur-accélération d'autres mécanismes d'usure qui ne sont pas censés être expérimentés dans l'application pratique. Notre expérimentation est un test à longue durée avec un temps de stress allant jusqu'à 2,000 heures. Cette thèse présente des résultats de mesure jusqu'à 230°C qui n'ont jamais été étudiés auparavant dans la littérature pour cette technologie.Les lois de vieillissement sont finalement intégrées dans un environnement de conception assistée par ordinateur (EDA) pour prédire l'évolution des paramètres électriques dégradés du transistor/circuit et l'estimation de la durée de vie en conséquence des effets du vieillissement. De plus, le test de fiabilité au niveau du circuit a été réalisé pour valider et vérifier les modèles de vieillissement proposés. Cette approche offre la possibilité d'évaluer et de simuler la dérive de spécification du CI due à l'effet du vieillissement dans la phase de conception précoceIn the past decades, the demand for complicated functionality and high-density integration for Integrated Circuits (ICs) has resulted in metal-oxide-silicon (MOS) devices' scaling down. In this scenario, the reliability problems are the considerable concerns due to the device miniaturization, such as Hot Carrier Injection (HCI) and Bias Temperature Instability (BTI) that seriously impact the device performance. In some application fields where the cost of failure is extremely high such as space, oilfield, or healthcare, the device must be able to stably and reliably work, especially at an extensive temperature range. Although device failure mechanisms have been intensively investigated in the past, the investigations of these mechanisms at high temperatures are seldom studied.This thesis aims to develop the aging laws for 0.18µm CMOS technology to optimize circuit design for a targeted lifetime under extreme temperatures. We conducted an intensive aging test campaign for both nMOS and pMOS featuring several gate lengths. The intrinsic HCI and BTI mechanisms were characterized and modeled under typical operating voltage biases to avoid the risk of overaccelerating other wear-out mechanisms that are not supposed to be experienced in practical application. Our experiment is a long-term test with a stress time of up to 2,000 hours. This thesis presents measurement results up to 230°C that have never been studied before in the literature for this technology.The aging laws are finally integrated into an electronic design automation (EDA) environment to predict the evolution of the degraded transistor/circuit electrical parameters and the lifetime estimation due to the aging effects. In addition, the reliability test at the circuit level has been performed to validate and verify the proposed aging models. This approach offers the possibility to assess and simulate the IC specification drift due to the aging effect in the early design phase and optimize the circuit design over lifetime
3
Li, Binhong. "Etude de l'effet du vieillissement sur la compatibilité électromagnétique des circuits intégrés." Thesis, Toulouse, INSA, 2011. http://www.theses.fr/2011ISAT0033/document.
Анотація:
Avec la tendance continue vers la technologie nanométrique et l'augmentation des fonctions complexes intègres dans les électroniques systèmes embarqués, Assurant la compatibilité électromagnétique (CEM) des systèmes électroniques est un grand défi. CEM est devenu une cause majeure de redesign des Circuits intègres (CI). D’ailleurs, les performances des circuits pourraient être affectés par les mécanismes de dégradation tels que hot carrier injection (HCI), negative bias temperature instability (NBTI), gate oxide breakdown, qui sont accélérés par les conditions d'exploitation extrême (haute / basse température, surcharge électrique, le rayonnement). Ce vieillissement naturel peut donc affecter les performances CEM des circuits intégrés.Les travaux développés dans notre laboratoire vise à clarifier le lien entre les dégradations induites par le vieillissement et les dérives CEM, de développer les modèles de prédiction et de proposer des "insensibles au cours du temps" structures pour CEM protection, afin de fournir des méthodes et des guidelines aux concepteurs d'équipements et CI pour garantir la CEM au cours de durée de vie de leurs applications. Ce sujet de recherche est encore sous-exploré en tant que communautés de recherche sur la «fiabilité IC» et «compatibilité électromagnétique IC» n’a souvent pas de chevauchement.Ce manuscrit de thèse introduit une méthode pour quantifier l'effet du vieillissement sur les CEM des circuits intégrés par la mesure et la simulation. Le premier chapitre donne un aperçu du contexte général et le deuxième chapitre est dédié a l’état de l'art de CEM des circuits intégrés et de problèmes de fiabilité IC. Les résultats expérimentaux de circuits CEM évolution sont présentés dans le troisième chapitre. Ensuite, le quatrième chapitre est consacré à la caractérisation et la modélisation des mécanismes de dégradation du CI. Un EMR modèle qui inclut l'élément le vieillissement pour prédire la dérive du niveau CEM de notre puce de test après stress est proposéWith the continuous trend towards nanoscale technology and increased integration of complex electronic functions in embedded systems, ensuring the electromagnetic compatibility (EMC) of electronic systems is a great challenge. EMC has become a major cause of IC redesign. Meanwhile, ICs performance could be affected by the degradation mechanisms such as hot carrier injection (HCI), negative bias temperature instability(NBTI), gate oxide breakdown, which are accelerated by the harsh operation conditions (high/low temperature, electrical overstress, radiation). This natural aging can thus affect EMC performances of ICs. The work developed in our laboratory aims at clarifying the link between ageing induced IC degradations and related EMC drifts, developing prediction models and proposing “time insensitive” EMC protection structures, in order to provide methods and guidelines to IC and equipment designers to ensure EMC during lifetime of their applications. This research topic is still under-explored as research communities on “IC reliability” and “IC electromagnetic compatibility” has often no overlap. The PhD manuscript introduced a methodology to quantify the effect of ageing on EMC of ICs by measurement and simulation. The first chapter gives an overview of the general context and the second chapter states the EMC of ICs state of the art and IC reliability issues. The experimental results of ICs EMC evolution are presented in the third chapter. Then, the fourth chapter is dedicated to the characterization and modeling IC degradation mechanism. An EMR model which includes the ageing element to predict our test chip’s EMC level drift after stress is proposed
4
Bertolini, Clément. "Estimation à haut-niveau des dégradations temporelles dans les processeurs : méthodologie et mise en oeuvre logicielle." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00952867.
Анотація:
Actuellement, les circuits numériques nécessitent d'être de plus en plus performants. Aussi, les produits doivent être conçus le plus rapidement possible afin de gagner les précieuses parts de marché. Les méthodes rapides de conception et l'utilisation de MPSoC ont permis de satisfaire à ces exigences, mais sans tenir compte précisément de l'impact du vieillissement des circuits sur la conception. Or les MPSoC utilisent les technologies de fabrication les plus récentes et sont de plus en plus soumis aux défaillances matérielles. De nos jours, les principaux mécanismes de défaillance observés dans les transistors des MPSoC sont le HCI et le NBTI. Des marges sont alors ajoutées pour que le circuit soit fonctionnel pendant son utilisation, en considérant le cas le plus défavorable pour chaque mécanisme. Ces marges deviennent de plus en plus importantes et diminuent les performances attendues. C'est pourquoi les futures méthodes de conception nécessitent de tenir compte des dégradations matérielles en fonction de l'utilisation du circuit. Dans cette thèse, nous proposons une méthode originale pour simuler le vieillissement des MPSoC à haut niveau d'abstraction. Cette méthode s'applique lors de la conception du système c.-à-d. entre l'étape de définition des spécifications et la mise en production. Un modèle empirique permet d'estimer les dégradations temporelles en fin de vie d'un circuit. Un exemple d'application est donné pour un processeur embarqué et les résultats pour un ensemble d'applications sont reportés. La solution proposée permet d'explorer différentes configurations d'une architecture MPSoC pour comparer le vieillissement. Aussi, l'application la plus sévère pour le vieillissement peut être identifiée.
5
Chen, Chang-Chih. "System-level modeling and reliability analysis of microprocessor systems." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53033.
Анотація:
Frontend and backend wearout mechanisms are major reliability concerns for modern microprocessors. In this research, a framework which contains modules for negative bias temperature instability (NBTI), positive bias temperature instability (PBTI), hot carrier injection (HCI), gate-oxide breakdown (GOBD), backend time-dependent dielectric breakdown (BTDDB), electromigration (EM), and stress-induced voiding (SIV) is proposed to analyze the impact of each wearout mechanism on state-of-art microprocessors and to accurately estimate microprocessor lifetimes due to each wearout mechanism. Taking into account the detailed thermal profiles, electrical stress profiles and a variety of use scenarios, composed of a fraction of time in operation, a fraction of time in standby, and a fraction of time when the system is off, this work provides insight into lifetime-limiting wearout mechanisms, along with the reliability-critical microprocessor functional units for a system. This enables circuit designers to know if their designs will achieve an adequate lifetime and further make any updates in the designs to enhance reliability prior to committing the designs to manufacture.
6
Lakhdari, Hacène. "Etude par technique spectroscopique de capacite transitoire des defauts a l'interface semiconducteur-isolant." Paris 6, 1988. http://www.theses.fr/1988PA066341.
Анотація:
Explication du comportement inhabituel de certaines structures mos en dlts (non-saturation du spectre dlts pour un remplissage total de la densite d'etats d'interface) par une interaction par effet tunnel entre les porteurs libres du semiconducteur et les defauts des premieres couches d'oxyde (etats lents). Etude de la degradation des interfaces si-sio::(2) sous injection d'electrons chauds en comparant la cinetique de creation des etats lents et rapides. Etude des defauts induits par plasma ionique reactif
7
Tseng, Shun-Shing, and 曾順星. "ILFD Using Dual Injection MOSFETs and Hot-Carrier Effects." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/5tk2a9.
Анотація:
碩士國立臺灣科技大學
電子工程系
102
First, A wide operation range parallel resonant divide-by-3 injection-locked frequency divider (ILFD) using a standard 0.18 μm CMOS process is presented. The ÷3 ILFD circuit is realized with a parallel resonant cross-coupled n-core MOS LC-tank oscillator. A tunable MOSFET resistor is used to tune the oscillation frequency and widens the operation range. Two direct-injection MOSFETs in series are used as a frequency doubler and a dynamic linear mixer to widen the locking range. The core power consumption of the ILFD core is 4.896 mW. At the incident power of 0 dBm, and the supply voltage of 0.8V, the maximum locking range is 1.6 GHz, from 10.6 GHz to 12.2 GHz and the operation range percentage of 47.6%, from 5 GHz to 13 GHz Secondly, we A wide locking and operation range parallel resonant divide-by-2/4 injection-locked frequency divider (ILFD) using a standard 0.18 μm CMOS process is presented. The ÷4/2 ILFD circuit is realized with a parallel resonant cross-coupled n-core MOS LC-tank oscillator. The ILFD uses a tunable resonator to have both wide operation and wide locking range. At the supply voltage of 0.92V, the core power consumption of the ILFD core is 7.9 mW. At the incident power of 0 dBm, the divide-by-2 locking range is 6 GHz, from 4.9 GHz to 10.9 GHz and the divide-by-4 locking range is 1.8 GHz, from 10.4 GHz to 12.2 GHz. The ILFD resonator can operates as a dual-resonance resonator or a single-resonance resonator. Finally, we investigates hot carrier (HC) effect on the RF characteristics of a wide-locking range divide-by-4 injection-locked frequency divider (ILFD). The ILFD was implemented in the TSMC 0.18 μm CMOS process. High supply voltage stresses were applied at room temperature on the ILFD. The main observed degradation is a decrease in power consumption due to channel mobility degradation. It was also found that the phase noises in both the free-running and locked state increase with stress time. The locking range of ILFD decreases with stress time and the optimized bias of injection transistor for the largest locking range shifts versus stress time.
8
Lin, Fa-Bo, and 林法伯. "Design of Injection Locked Frequency Divider and Hot Carrier Effects of Injection Locked Frequency Divider." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/50431791342256963033.
Анотація:
碩士國立臺灣科技大學
電子工程系
102
This thesis presents two Injection Locked Frequency Dividers (ILFDs). First one is a wide-locking range Injection Locked Frequency Divider by 2. Second one is a wide-locking range Injection Locked Frequency Divider by 4. Finally, we present two Injection locked frequency divider’s hot-carrier effects experiment. The above circuits are fabricated in the TSMC 0.18 μm CMOS process and 0.18um SiGe process. Firstly, we present a novel wide locking range divide-by-2 injection-locked frequency divider (ILFD) and the divider is implemented in the TSMC 0.18 μm 1P6M CMOS process. The divide-by-2 ILFD is based on a cross-coupled voltage-controlled oscillator (VCO)consist of a parallel-tuned LC resonator as well as injection MOSFETs with source voltage coupled from VCO output and the injection MOSFET is a linear mixer. At the drain-source bias of 0.9 V, and at the incident power of 0 dBm the locking range of the divide-by-2 ILFD is 6.4 GHz, from the incident frequency 3.7 GHz to 10.1 GHz, the percentage is 92.75%. A novel wide locking range divide-by-4 injection-locked frequency divider (ILFD) is proposed in the thesis and was implemented in the TSMC 0.18 μm 1P6M CMOS process. The divide-by-4 ILFD is based on a cross-coupled voltage-controlled oscillator (VCO) with a parallel-tuned LC resonator and injection MOSFETs with source voltage coupled from VCO output and the injection MOSFET is a linear mixer. At the drain-source bias of 0.9 V, and at the incident power of 0 dBm the locking range of the divide-by-4 is 2.7 GHz, from the incident frequency 14.1 GHz to 16.8 GHz, the percentage is 17.47%. The core power consumption is 16.56 mW. The die area is 0.839 ×0.566 mm2. Secondly, a divide-by-2 injection-locked frequency divider (ILFD) is designed for hot-carrier stress experimental study. The ILFD is made of a parallel-tuned cross-coupled voltage-controlled oscillator and a capacitive direct-injection MOSFET composite, consisted two MIM capacitors in series with an injection MOSFET. The injection MOSFET is first dc-stressed, and degradation in locking range in the post-stress ILFD was found. Then the whole ILFD is overvoltage-stressed, and degradation in locking range in the post-stress ILFD was also found. The latter stress reduces the current consumption and output power, while the former increases the current consumption and output power. Finally, a divide-by-2 injection-locked frequency divider (ILFD) is designed in the 0.18μm CMOS technology for hot-carrier stress experimental study. The ILFD was tested at two bias conditions. At fixed supply voltage, the stress damage is larger when the gate of injection MOSFET is dc-biased below the supply voltage rather than equal to the supply voltage. The stress cause the degradation of locking range, current consumption and shifts the oscillation frequency.
9
Hsieh, Jen-Hsiang, and 謝仁翔. "Design and Hot Carrier Stress Effect ofNovel Injection-Locked Frequency Divider." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/42871692762723508514.
Анотація:
碩士國立臺灣科技大學
電子工程系
101
In the RF transceiver, PLL characteristics are very important, PLL to including Phase Frequency Detector (PFD),Charge Pump (CP),Loop Filter (LF),Voltage Controlled Oscillator (VCO), and Frequency Divider (FD), In order to pursue low-power, low phase noise, wide operating frequency range, Among them, the most important performance of the VCO and Divider. First, this thesis presents two divider-by-3 injection locked frequency dividers. In the first circuit, we use internal feedback to enhance locking frequency, the ILFD was implemented with the TSMC 0.18 μm SiGe 3P6M BiCMOS process, and the core power consumption is 13.2 mW at the dc drain-source bias of 0.8 V. and tuning range is from 3.079 to 3.163 GHz. At the input power of 0 dBm, the locking range is from 8.9 GHz to 10.8 GHz (19.28 %), the operation range is from 8.9 to 11 GHz(21.1%), and the die area is 0.620 * 0.871 mm2. Secondly, we presents a mixer twice in divider-by-3 injection locked frequency dividers, the ILFD was implemented with the TSMC 0.18 μm 1P6M CMOS process, and the core power consumption is 11.496 mW at the dc drain-source bias of 0.8 V. The tuning range is from 4.32 to 3.78 GHz, At the input power of 0 dBm, the locking range is from 10.5 GHz to 13.5 GHz (25 %), while the operation range is from 9.9 to 13.5 GHz(30.76%), The die area is 0.659 * 0.887 mm2. Then, we measure hot carrier stress effects on the different parameters of these two circuit of circuit architecture, such as phase noise, locking range, current, tuning range, we do analysis and discussion for the measured result. Finally, we presents a Triple-Band Voltage-Controlled Oscillator, the VCO was implemented with the TSMC 0.18 μm 1P6M CMOS process, and the core power consumption is 3.735 mW at the dc drain-source bias of 0.75 V. The VCO can generate differential signals in the frequency range of 6.98-7.41GHz, 5.28-5.31GHz, and 4.27-4.49GHz. The die area is 0.568*1.189 mm2.
10
Yih, Cherng-Ming, and 易成名. "Investigation of Hot-Carrier Injection Induced Reliability Issues in Flash Memories." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/73427801549497138777.
Анотація:
博士國立交通大學
電子工程系
87
Hot carrier induced reliability issues have become increasingly important for miniaturized flash memory design. These reliability issues include hot carrier related issues, such as oxide damage, program/erase cycling endurance, disturbance, and data retention. In this dissertation, the hot-carrier injection induced reliability problems in stacked-gate flash memories is investigated. First, a new model based on the charge-balance theory was proposed to accurately calculate the floating gate voltage. Based on the new model, the method to determine the capacitive coupling coefficients and a compact SPICE model was developed. Then, an oxide damage characterization method was developed for simultaneously determining the lateral distributions of interface states (Nit) and oxide charges (Qox) under both channel-hot-electron programming bias and source FN erase bias stress conditions. According to the extracted profiles of Nit and Qox, a new gate current model was successfully developed for the first time by taking the hot-electron stress generated Nit and Qox into account. In this model, we suggest that Nit filled with electrons will serve as a new scattering center and reduce the hot-electron injection probability. The generated Qox is also introduced as an additional factor affecting the potential barrier at the Si-SiO2 interface. Moreover, the oxide-field dependent stress-induced leakage current (SILC) as well as its related disturbance on the source FN erased flash memory has been studied by using a new approach. The salient features of the method are two fold. One is that the individual contributions of SILC and disturbance due to either carrier charging/discharging in the oxide or positive charge-assisted/trap-assisted tunneling (PCAT/TAT) of electrons into the floating gate can be separated. The other one is that it is very sensitive to determine the ultra-low SILC (< 10-20 A). In this study, we first observed that the generated Nit dominates the gate current degradation not only at the IB,max stress condition but also at the IG,max stress condition. The major programming degradation mechanisms of flash memory cells after P/E cycles due to Nit was also identified. In addition, we also observed that the carrier charging/discharging in the oxide is the main disturb mechanism at low oxide field. At high oxide field, PCAT/TAT of electrons into the floating gate is the major cause for the disturb failure.
Частини книг з теми "Hot Carriers Injection":
1
Huard, Vincent, Florian Cacho, Xavier Federspiel, and Pascal Mora. "Hot-Carrier Injection Degradation in Advanced CMOS Nodes: A Bottom-Up Approach to Circuit and System Reliability." In Hot Carrier Degradation in Semiconductor Devices, 401–44. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-08994-2_14.
2
Bhargava, Mudit, and Ken Mai. "A High Reliability PUF Using Hot Carrier Injection Based Response Reinforcement." In Cryptographic Hardware and Embedded Systems - CHES 2013, 90–106. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-40349-1_6.
3
Kühn, Johannes Maximilian, Oliver Bringmann, and Wolfgang Rosenstiel. "Increasing Reliability Using Adaptive Cross-Layer Techniques in DRPs: Just-Safe-Enough Responses to Reliability Threats." In Dependable Embedded Systems, 121–38. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-52017-5_5.
Анотація:
AbstractThe developments in the semiconductor industry as predicted by institutions such as the ITRS present a difficult question to hardware and software developers alike: How to implement increasingly complex, power hungry, and critical applications reliably in today’s and tomorrow’s semiconductor technology? The present trend of semiconductor technology is characterized by a sharp increase in complexity, cost, and delicacy. Also, it does not scale along the demands which are still based on and often exceed Moore’s Law. In this chapter, we propose to exploit the architectural redundancies provided by potent, yet energy efficient massively parallel architectures, modeled using Dynamically Reconfigurable Processors (DRP). Using DRPs, we built an extensive cross-layer approach, offering different levels of reliability measures to operating system (OS) and software developers through low-cost hardware redundancy schemes and appropriate physical operating condition tuning. On the hardware side, online testing schemes and error detection are deployed to trigger dynamic remapping to avoid the usage of faulty components. This approach is further complemented through hardware health monitoring that can detect reliability issues such as negative bias temperature instability (NBTI) or hot carrier injection (HCI) before they surface as an error as well as further tuning of operating conditions to delay such phenomena from surfacing.
4
"Hot Carrier Injection Instability." In Silicon RF Power MOSFETs, 243–74. WORLD SCIENTIFIC, 2005. http://dx.doi.org/10.1142/9789812569325_0010.
5
Pejovi, Momilo, Predrag Osmokrovi, Milica Pejovi, and Koviljka Stankovi. "Influence of Ionizing Radiation and Hot Carrier Injection on Metal-Oxide-Semiconductor Transistors." In Current Topics in Ionizing Radiation Research. InTech, 2012. http://dx.doi.org/10.5772/39263.
6
Vuillaume, D. "Chapter 4 Hot carrier injections in SIO2 and related instabilities in submicrometer mosfets." In New Insulators, Devices and Radiation Effects, 265–339. Elsevier, 1999. http://dx.doi.org/10.1016/s1874-5903(99)80010-x.
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Enoki, Toshiaki, Morinobu Endo, and Masatsugu Suzuki. "Highly Conductive Graphite Fibers." In Graphite Intercalation Compounds and Applications. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195128277.003.0012.
Анотація:
From the viewpoint of applications of GICs, a very interesting development is the enhancement in conductivity of the host graphite up to the range of metals, especially for pristine materials with fibrous forms. Much attention has been paid to the exploitation of the order of magnitude intercalation-induced enhancement of the electrical conductivity of graphite fibers for the fabrication of practical high-conductivity, lightweight conductors (Vogel et al., 1977; Goldberg and Kalnim, 1981; Manini et al., 1983, 1985; Murday et al., 1984; Meschi et al., 1986; Natarajan and Woollam, 1983; Natarajan et al., 1983a). The fiber geometry (large aspect length/diameter) ratio offers advantages relative to highly oriented pyrolytic graphite (HOPG) or bulk graphite for the measurement of several of the transport properties of GICs and for increasing the compositional stability of GICs both under ambient conditions and at elevated temperatures (Endo et al., 1981, 1983a). For bulk GICs, intercalation increases the density of carriers by the injection of electrons into the graphite planes in the case of donor guest species, and by injection of holes in the case of acceptor type (see Chapters 5 and 6). The intercalation-induced decrease in carrier mobility that results from the increased scattering by defects and the increased effective mass is outweighed by the larger increase in carrier density, resulting in a large conductivity enhancement as discussed in Section 6.1. The carriers are localized in the graphene planes, and for high-stage compounds (n ≥ 2) the carrier density falls off rapidly with distance from the graphite bounding layer owing to the screening of the charged intercalate layer by the surrounding graphite bounding layers. From an application standpoint, many of the applications of intercalated carbon fibers exploit the high specific conductivity of GICs, which can be expressed as a figure of merit in terms of the conductivity σ divided by the mass density ρm; for a good conductor like copper this is ~ 6 x 10−2 cm /gμΩ. For example, intercalated carbon fibers can provide a lightweight conductor for huge aircraft or motor vehicles, in which, respectively, about 1.5 tonne or 30 kg conventional metallic conductor is used.
8
Kennel, Charles F. "Coordination Of The Geosynchronous And Auroral Substorms." In Convection and Substorms. Oxford University Press, 1996. http://dx.doi.org/10.1093/oso/9780195085297.003.0017.
Анотація:
Studies using data from the ATS-5 geosynchronous spacecraft revealed a clear relationship between midnight region injection events near the spacecraft and auroral displays near the ATS magnetic conjugate point (Hones et al., 1971a; Mende et al., 1972; Eather et al., 1976; Mende and Shelley, 1976). A comparison of ATS-5 particle and magnetic field data with all-sky photographs taken at the conjugate point, Great Whale River, indicated that an injection at geostationary orbit generally corresponded to the brightening of the onset arc when the spacecraft was in the midnight sector (Akasofu et al., 1974). Results such as this whetted the collective appetite. How closely can the initial onset and injection be related to one another in time, do the onset and injection start on the same field field line, does the westward propagation of dipolarization correspond to the westward surge, can one relate the fine structures of the auroral expansion and the dipolarization? As time passed, increasingly precise answers have been given to these and similar questions, and auroral and geosynchronous substorm phenomenology has become more tightly integrated. In this chapter, we sample some of the evidence that supports this statement. The GEOS 2 spacecraft was stationed with its magnetic conjugate point near Kiruna, Sweden, so that the conjugate aurora could be studied with the extensive network of ground-based observatories in Scandinavia (Knott, 1975; Knott et al., 1979). In the first part of this chapter, we review some of the correlation studies carried out in the GEOS 2 project. In one particular series of four substorms, it was found that the dipolarization occurred at the same time as the aurora brightened and expanded poleward over the ground conjugate region (Section 14.2). In another case, a dispersionless injection at GEOS 2 corresponded to an intensification of the auroral X-ray band in Scandinavia (Section 14.2). Westward surges at the auroral conjugate point were associated with dipolarization at the spacecraft on a statistical basis (Section 14.3). Finally, the close relationship between both the auroral and geostationary substorm phenomena was extended to small spatio-temporal scales.
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Voren, Robert van, and Robert Keukens. "The abuse of psychiatry." In Psychiatric Ethics, edited by Sidney Bloch and Stephen A. Green, 143–56. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780198839262.003.0007.
Анотація:
Abuse of psychiatry was in the Soviet Union, for several decades, a State policy to quell dissent, and was carried out in collaboration with the then leadership of Soviet psychiatry. Approximately one-third of all political prisoners were subjected to this practice. The Soviet case has been taken as the main example. However, this branch of medicine has been misused elsewhere, in particular, in the Eastern Bloc in the 1980s, and in the People’s Republic of China in the late 1990s. Before World War II, on the pretext of setting up a merciful euthanasia programme, the Nazi regime made medical and nursing staff kill, by injection and gassing, tens of thousands of patients suffering from an incurable physical or mental illness. The chapter ends with thoughts on how the political abuse of psychiatry can be prevented.
10
Haq, Shamsul. "Effect of Materials Content on Dimensional Stability, Nano Roughness and Interfaced Morphology for Virgin or Recycled Polypropylene Based Wood Composites." In Engineered Wood Products for Construction [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99588.
Анотація:
The compositions of mango wood-polypropylene composites (WPCs) are formulated, with different compositions of virgin polypropylene (PP) or recycled PP, mango wood waste and a coupling agent. The compositions are fabricated via melt extrusion compounding pursued by injection hot molding. The tests of the prepared compositions are carried out for, water absorption, thickness swelling, surface properties at a nano-scale and interfaced morphology. Comparative study of WPCs composition has done on respective properties. All processing variable conditions are constant for different compositions. The recycled PP based wood composites with or without the coupling agent possessed superior properties in comparison to virgin PP based composites. FESEM images show that coupled composite is having the better bonding strength and smoothness along with a higher dimensional stability in comparison to none coupled composite. Future endeavor should be focused on optimizing the composition of reinforcement wood and recycled plastics matrix according to intended application. The quality of WPCs can also be improved with the co-ordination of latest development in technology and processing technique relevant to them. WPCs study supports “turning waste into something useful”. This provides the mileage in price performance ratio and also the product’s environmental footprints to be adjusted to suit the products application.
Тези доповідей конференцій з теми "Hot Carriers Injection":
1
Matsui, Takayuki, Yi Li, Rupert F. Oulton, Lesley F. Cohen, and Stefan A. Maier. "Plasmonic Hot Carrier Detection via SrTiO3 Interfacial Layer." In JSAP-OSA Joint Symposia. Washington, D.C.: Optica Publishing Group, 2018. http://dx.doi.org/10.1364/jsap.2018.19p_211b_12.
Анотація:
Energetic hot carrier injection from metal plasmonic structure to adjacent semiconductor lies at the center of the application of non-radiative decays, photochemical reactions and energy harvesting. Plasmonic hot-electron devices, till now, have been highly focused on a Schottky barrier structures to separate the energetic carriers before the thermalization. For instance, much efforts were putted in exploring high absorption structure with enough thin metal; enough thin compared to mean free path. However, interfacial engineering of the device; exploring a new device structure, have not been fully investigated.
2
Baeg, Sanghyeon, Pierre Chia, ShiJie Wen, and Richard Wong. "DRAM failure cases under hot-carrier injection." In 2011 18th IEEE International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA 2011). IEEE, 2011. http://dx.doi.org/10.1109/ipfa.2011.5992747.
3
Cacho, F., W. Arfaoui, P. Mora, X. Federspiel, V. Huard, and E. Dornel. "Modeling of hot carrier injection across technology scaling." In 2014 IEEE International Integrated Reliability Workshop Final Report (IIRW). IEEE, 2014. http://dx.doi.org/10.1109/iirw.2014.7049514.
4
Bolshakov, P., R. A. Rodriguez-Davila, M. Quevedo-Lopez, and C. D. Young. "Deconvolution of Hot Carrier and Cold Carrier Injection in ZnO TFTs." In 2020 IEEE Silicon Nanoelectronics Workshop (SNW). IEEE, 2020. http://dx.doi.org/10.1109/snw50361.2020.9131625.
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Lahbib, Insaf, Aziz Doukkali, Patrick Martin, Guy Imbert, and Denis Raoulx. "Hot carrier injection effect on threshold voltage of NMOSFETs." In 2015 11th Conference on Ph.D. Research in Microelectronics and Electronics (PRIME). IEEE, 2015. http://dx.doi.org/10.1109/prime.2015.7251360.
6
Mitsuhashi, J., S. Nakao, and T. Matsukawa. "Mechanical stress and hydrogen effects on hot carrier injection." In 1986 International Electron Devices Meeting. IRE, 1986. http://dx.doi.org/10.1109/iedm.1986.191199.
7
Grupen, Matthew E., and Karl Hess. "Hot carrier effects in conventional injection and tunneling injection quantum well laser diodes." In Photonics West '97, edited by Marek Osinski and Weng W. Chow. SPIE, 1997. http://dx.doi.org/10.1117/12.275598.
8
Lee, Dong Seup, Dhanoop Varghese, Arif Sonnet, Jungwoo Joh, Archana Venugopal, and Srikanth Krishnan. "Impact of self-heating effect in hot carrier injection modeling." In 2018 IEEE 30th International Symposium on Power Semiconductor Devices and ICs (ISPSD). IEEE, 2018. http://dx.doi.org/10.1109/ispsd.2018.8393666.
9
Sabnis, A. G., and J. T. Nelson. "Characterization of Si/SiO2interface degradation due to hot-carrier injection." In 1985 International Electron Devices Meeting. IRE, 1985. http://dx.doi.org/10.1109/iedm.1985.190889.
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Rao, R. A., R. F. Steimle, M. Sadd, C. Swift, R. Muralidhar, B. Hradsky, S. Straub, E. Prinz, J. Yater, and B. E. White Jr. "Hot Carrier Injection/Fowler Nordheim Erase Silicon Nanocrystal Memory Cell." In 2003 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2003. http://dx.doi.org/10.7567/ssdm.2003.b-6-1.
Звіти організацій з теми "Hot Carriers Injection":
1
Ficht, Thomas, Gary Splitter, Menachem Banai, and Menachem Davidson. Characterization of B. Melinensis REV 1 Attenuated Mutants. United States Department of Agriculture, December 2000. http://dx.doi.org/10.32747/2000.7580667.bard.
Анотація:
Brucella Mutagenesis (TAMU) The working hypothesis for this study was that survival of Brucella vaccines was directly related to their persistence in the host. This premise is based on previously published work detailing the survival of the currently employed vaccine strains S19 and Rev 1. The approach employed signature-tagged mutagenesis to construct mutants interrupted in individual genes, and the mouse model to identify mutants with attenuated virulence/survival. Intracellular survival in macrophages is the key to both reproductive disease in ruminants and reticuloendothelial disease observed in most other species. Therefore, the mouse model permitted selection of mutants of reduced intracellular survival that would limit their ability to cause reproductive disease in ruminants. Several classes of mutants were expected. Colonization/invasion requires gene products that enhance host-agent interaction or increase resistance to antibacterial activity in macrophages. The establishment of chronic infection requires gene products necessary for intracellular bacterial growth. Maintenance of chronic infection requires gene products that sustain a low-level metabolism during periods characterized little or no growth (1, 2). Of these mutants, the latter group was of greatest interest with regard to our originally stated premise. However, the results obtained do not necessarily support a simplistic model of vaccine efficacy, i.e., long-survival of vaccine strains provides better immunity. Our conclusion can only be that optimal vaccines will only be developed with a thorough understanding of host agent interaction, and will be preferable to the use of fortuitous isolates of unknown genetic background. Each mutant could be distinguished from among a group of mutants by PCR amplification of the signature tag (5). This approach permitted infection of mice with pools of different mutants (including the parental wild-type as a control) and identified 40 mutants with apparently defective survival characteristics that were tentatively assigned to three distinct classes or groups. Group I (n=13) contained organisms that exhibited reduced survival at two weeks post-infection. Organisms in this group were recovered at normal levels by eight weeks and were not studied further, since they may persist in the host. Group II (n=11) contained organisms that were reduced by 2 weeks post infection and remained at reduced levels at eight weeks post-infection. Group III (n=16) contained mutants that were normal at two weeks, but recovered at reduced levels at eight weeks. A subset of these mutants (n= 15) was confirmed to be attenuated in mixed infections (1:1) with the parental wild-type. One of these mutants was eliminated from consideration due to a reduced growth rate in vitro that may account for its apparent growth defect in the mouse model. Although the original plan involved construction of the mutant bank in B. melitensis Rev 1 the low transformability of this strain, prevented accumulation of the necessary number of mutants. In addition, the probability that Rev 1 already carries one genetic defect increases the likelihood that a second defect will severely compromise the survival of this organism. Once key genes have been identified, it is relatively easy to prepare the appropriate genetic constructs (knockouts) lacking these genes in B. melitensis Rev 1 or any other genetic background. The construction of "designer" vaccines is expected to improve immune protection resulting from minor sequence variation corresponding to geographically distinct isolates or to design vaccines for use in specific hosts. A.2 Mouse Model of Brucella Infection (UWISC) Interferon regulatory factor-1-deficient (IRF-1-/- mice have diverse immunodeficient phenotypes that are necessary for conferring proper immune protection to intracellular bacterial infection, such as a 90% reduction of CD8+ T cells, functionally impaired NK cells, as well as a deficiency in iNOS and IL-12p40 induction. Interestingly, IRF-1-/- mice infected with diverse Brucella abortus strains reacted differently in a death and survival manner depending on the dose of injection and the level of virulence. Notably, 50% of IRF-1-/- mice intraperitoneally infected with a sublethal dose in C57BL/6 mice, i.e., 5 x 105 CFU of virulent S2308 or the attenuated vaccine S19, died at 10 and 20 days post-infection, respectively. Interestingly, the same dose of RB51, an attenuated new vaccine strain, did not induce the death of IRF-1-/- mice for the 4 weeks of infection. IRF-1-/- mice infected with four more other genetically manipulated S2308 mutants at 5 x 105 CFU also reacted in a death or survival manner depending on the level of virulence. Splenic CFU from C57BL/6 mice infected with 5 x 105 CFU of S2308, S19, or RB51, as well as four different S2308 mutants supports the finding that reduced virulence correlates with survival Of IRF-1-/- mice. Therefore, these results suggest that IRF-1 regulation of multi-gene transcription plays a crucial role in controlling B. abortus infection, and IRF-1 mice could be used as an animal model to determine the degree of B. abortus virulence by examining death or survival. A3 Diagnostic Tests for Detection of B. melitensis Rev 1 (Kimron) In this project we developed an effective PCR tool that can distinguish between Rev1 field isolates and B. melitensis virulent field strains. This has allowed, for the first time, to monitor epidemiological outbreaks of Rev1 infection in vaccinated flocks and to clearly demonstrate horizontal transfer of the strain from vaccinated ewes to unvaccinated ones. Moreover, two human isolates were characterized as Rev1 isolates implying the risk of use of improperly controlled lots of the vaccine in the national campaign. Since atypical B. melitensis biotype 1 strains have been characterized in Israel, the PCR technique has unequivocally demonstrated that strain Rev1 has not diverted into a virulent mutant. In addition, we could demonstrate that very likely a new prototype biotype 1 strain has evolved in the Middle East compared to the classical strain 16M. All the Israeli field strains have been shown to differ from strain 16M in the PstI digestion profile of the omp2a gene sequence suggesting that the local strains were possibly developed as a separate branch of B. melitensis. Should this be confirmed these data suggest that the Rev1 vaccine may not be an optimal vaccine strain for the Israeli flocks as it shares the same omp2 PstI digestion profile as strain 16M.
2
Altstein, Miriam, and Ronald J. Nachman. Rational Design of Insect Control Agent Prototypes Based on Pyrokinin/PBAN Neuropeptide Antagonists. United States Department of Agriculture, August 2013. http://dx.doi.org/10.32747/2013.7593398.bard.
Анотація:
The general objective of this study was to develop rationally designed mimetic antagonists (and agonists) of the PK/PBAN Np class with enhanced bio-stability and bioavailability as prototypes for effective and environmentally friendly pest insect management agents. The PK/PBAN family is a multifunctional group of Nps that mediates key functions in insects (sex pheromone biosynthesis, cuticular melanization, myotropic activity, diapause and pupal development) and is, therefore, of high scientific and applied interest. The objectives of the current study were: (i) to identify an antagonist biophores (ii) to develop an arsenal of amphiphilic topically active PK/PBAN antagonists with an array of different time-release profiles based on the previously developed prototype analog; (iii) to develop rationally designed non-peptide SMLs based on the antagonist biophore determined in (i) and evaluate them in cloned receptor microplate binding assays and by pheromonotropic, melanotropic and pupariation in vivo assays. (iv) to clone PK/PBAN receptors (PK/PBAN-Rs) for further understanding of receptor-ligand interactions; (v) to develop microplate binding assays for screening the above SMLs. In the course of the granting period A series of amphiphilic PK/PBAN analogs based on a linear lead antagonist from the previous BARD grant was synthesized that incorporated a diverse array of hydrophobic groups (HR-Suc-A[dF]PRLa). Others were synthesized via the attachment of polyethylene glycol (PEG) polymers. A hydrophobic, biostablePK/PBAN/DH analog DH-2Abf-K prevented the onset of the protective state of diapause in H. zea pupae [EC50=7 pmol/larva] following injection into the preceding larval stage. It effectively induces the crop pest to commit a form of ‘ecological suicide’. Evaluation of a set of amphiphilic PK analogs with a diverse array of hydrophobic groups of the formula HR-Suc-FTPRLa led to the identification of analog T-63 (HR=Decyl) that increased the extent of diapause termination by a factor of 70% when applied topically to newly emerged pupae. Another biostablePK analog PK-Oic-1 featured anti-feedant and aphicidal properties that matched the potency of some commercial aphicides. Native PK showed no significant activity. The aphicidal effects were blocked by a new PEGylated PK antagonist analog PK-dF-PEG4, suggesting that the activity is mediated by a PK/PBAN receptor and therefore indicative of a novel and selective mode-of-action. Using a novel transPro mimetic motif (dihydroimidazole; ‘Jones’) developed in previous BARD-sponsored work, the first antagonist for the diapause hormone (DH), DH-Jo, was developed and shown to block over 50% of H. zea pupal diapause termination activity of native DH. This novel antagonist development strategy may be applicable to other invertebrate and vertebrate hormones that feature a transPro in the active core. The research identifies a critical component of the antagonist biophore for this PK/PBAN receptor subtype, i.e. a trans-oriented Pro. Additional work led to the molecular cloning and functional characterization of the DH receptor from H. zea, allowing for the discovery of three other DH antagonist analogs: Drosophila ETH, a β-AA analog, and a dF analog. The receptor experiments identified an agonist (DH-2Abf-dA) with a maximal response greater than native DH. ‘Deconvolution’ of a rationally-designed nonpeptide heterocyclic combinatorial library with a cyclic bis-guanidino (BG) scaffold led to discovery of several members that elicited activity in a pupariation acceleration assay, and one that also showed activity in an H. zea diapause termination assay, eliciting a maximal response of 90%. Molecular cloning and functional characterization of a CAP2b antidiuretic receptor from the kissing bug (R. prolixus) as well as the first CAP2b and PK receptors from a tick was also achieved. Notably, the PK/PBAN-like receptor from the cattle fever tick is unique among known PK/PBAN and CAP2b receptors in that it can interact with both ligand types, providing further evidence for an evolutionary relationship between these two NP families. In the course of the granting period we also managed to clone the PK/PBAN-R of H. peltigera, to express it and the S. littoralis-R Sf-9 cells and to evaluate their interaction with a variety of PK/PBAN ligands. In addition, three functional microplate assays in a HTS format have been developed: a cell-membrane competitive ligand binding assay; a Ca flux assay and a whole cell cAMP ELISA. The Ca flux assay has been used for receptor characterization due to its extremely high sensitivity. Computer homology studies were carried out to predict both receptor’s SAR and based on this analysis 8 mutants have been generated. The bioavailability of small linear antagonistic peptides has been evaluated and was found to be highly effective as sex pheromone biosynthesis inhibitors. The activity of 11 new amphiphilic analogs has also been evaluated. Unfortunately, due to a problem with the Heliothis moth colony we were unable to select those with pheromonotropic antagonistic activity and further check their bioavailability. Six peptides exhibited some melanotropic antagonistic activity but due to the low inhibitory effect the peptides were not further tested for bioavailability in S. littoralis larvae. Despite the fact that no new antagonistic peptides were discovered in the course of this granting period the results contribute to a better understanding of the interaction of the PK/PBAN family of Nps with their receptors, provided several HT assays for screening of libraries of various origin for presence of PK/PBAN-Ragonists and antagonists and provided important practical information for the further design of new, peptide-based insecticide prototypes aimed at the disruption of key neuroendocrine physiological functions in pest insects.