• Title/Summary/Keyword: interface energy

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Analysis of SOHOS Flash Memory with 3-level Charge Pumping Method

  • Yang, Seung-Dong;Kim, Seong-Hyeon;Yun, Ho-Jin;Jeong, Kwang-Seok;Kim, Yu-Mi;Kim, Jin-Seop;Ko, Young-Uk;An, Jin-Un;Lee, Hi-Deok;Lee, Ga-Won
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.1
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    • pp.34-39
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    • 2014
  • This paper discusses the 3-level charge pumping (CP) method in planar-type Silicon-Oxide-High-k-Oxide-Silicon (SOHOS) and Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) devices to find out the reason of the degradation of data retention properties. In the CP technique, pulses are applied to the gate of the MOSFET which alternately fill the traps with electrons and holes, thereby causing a recombination current Icp to flow in the substrate. The 3-level charge pumping method may be used to determine not only interface trap densities but also capture cross sections as a function of trap energy. By applying this method, SOHOS device found to have a higher interface trap density than SONOS device. Therefore, degradation of data retention characteristics is attributed to the many interface trap sites.

Effect of the Deep Donor Level on the Interface Electron Density ($Al_xGa_{1-x}As$-GaAs 이종접합에서 deep donor level 이 interface electron density에 미치는 영향)

  • Nam, Seaung-Hyun;Jung, Hak-Kee;Lee, Moon-Key;Kim, Bong-Ryul
    • Proceedings of the KIEE Conference
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    • 1987.07a
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    • pp.465-468
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    • 1987
  • This paper describes a model to calculate the equilibrium electron density of MODFET at the interface that takes into account the simultaneous shallow and deep level in the Al-GaAs layer. In the present study we have made an investigation of the interface electron density with different values of the AlGaAs doping density and spacer layer thickness, considering simultaneously two doner levels. In this case, the ratio of the shallow to the deep donor concentraction is considered. From the comparison with early experimental results we could find the deep level and that the deep donor concentration is about 50% with the Al mole fraction X ${\sim}0.3$, activation energy Edx=65meV, temperature $77^{\circ}K$ and spacer thickness range $50A{\sim}100A$. Also we have investigated the effect of the temperature. As temperature increase, at critical mole fraction X the nature of the donor concentration changes from $\Gamma$ to L and X.

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A Study on the Si-SiO$_2$Interface State Characteristics of Nonvolatile SNOS FET Memories using The Charge Pumping Method (Charge Pumping 방법을 이용한 비휘발성 SNOS FET기억소자의 Si-SiO$_2$계면상태 특성에 관한 연구)

  • 조성두;이상배;문동찬;서광열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1992.05a
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    • pp.82-85
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    • 1992
  • In this study, charge pumping method was used to investigate the Si-SiO$_2$interface characteristics of the nonvolatile SNOSFET memory devices, fabricated using the CMOS 1 Mbit processes (1.2$\mu\textrm{m}$ design rule), with thin oxide layer of 30${\AA}$ thick and nitride layer of 525${\AA}$ thick on the n-type silicon substrate (p-channel). Charge pumping current characteristics with the pulse base level were measured for various frequencies, falling times and rising times. By means of the charge dynamics in a non-steady state, the average Si-SiO$_2$interface state density and capture cross section were determined to be 3.565${\times}$10$\^$11/cm$\^$-2/eV$\^$-1/ and 4.834${\times}$10$\^$-16/$\textrm{cm}^2$, respectively. However Si-SiO$_2$ interface state densities were disributed 2.8${\times}$10$\^$-11/~5.6${\times}$10$\^$11/cm$\^$-2/~6${\times}$10$\^$11/cm$\^$-2/eV$\^$-1/ in the lover half of energy gap.

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Effect of Bonding Surface Laser Patterns on Interfacial Toughness of GFRP/Al Composite (GFRP/Al 복합재료의 접합부 레이저 패턴이 계면인성에 미치는 영향)

  • Woo Yong Sim;Yu Seong Yun;Oh Heon Kwon
    • Journal of the Korean Society of Safety
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    • v.38 no.2
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    • pp.1-7
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    • 2023
  • Fiber-metal laminates (FMLs) and polymer matrix composites (PMCs) are formed in various ways. In particular, FMLs in which aluminum is laminated as a reinforced layer are widely used. Also, glass fiber-reinforced plastics (GFRPs) are generally applied as fiber laminates. The bonding interface layer between the aluminum and fiber laminate exhibits low strength when subjected to hot press fabrication in the event of delamination fracture at the interface. This study presents a simple method for strengthening the interface bonding between the aluminum metal and GFRP layer of FML composites. The surfaces of the aluminum interface layer are engraved with three kinds of patterns by using the laser machine before the hot press works. Furthermore, the effect of the laser patterns on the interfacial toughness is investigated. The interfacial toughness was evaluated by the energy release rate (G) using an asymmetric double cantilever bending specimen (ADCB). From the experimental results, it was shown that the strip type pattern (STP) has the most proper pattern shape in GFRP/Al FML composites. Therefore, this will be considered a useful method for the safety assessment of FML composite structures.

Developing an interface strength technique using the laser shock method

  • James A. Smith;Bradley C. Benefiel;Clark L. Scott
    • Nuclear Engineering and Technology
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    • v.55 no.2
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    • pp.432-442
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    • 2023
  • Characterizing the behavior of nuclear reactor plate fuels is vital to the progression of advanced fuel systems. The states of pre- and post-irradiation plates need to be determined effectively and efficiently prior to and following irradiation. Due to the hostile post-irradiation environment, characterization must be completed remotely. Laser-based characterization techniques enable the ability to make robust measurements inside a hot-cell environment. The Laser Shock (LS) technique generates high energy shockwaves that propagate through the plate and mechanically characterizes cladding-cladding interfaces. During an irradiation campaign, two Idaho National Laboratory (INL) fabricated MP-1 plates had a fuel breach in the cladding-cladding interface and trace amounts of fission products were released. The objective of this report is to characterize the cladding-cladding interface strengths in three plates fabricated using different fabrication processes. The goal is to assess the risk in irradiating future developmental and production fuel plates. Prior LS testing has shown weaker and more variability in bond strengths within INL MP-1 reference plates than in commercially produced vendor plates. Three fuel plates fabricated with different fabrication processes will be used to bound the bond strength threshold for plate irradiation insertion and assess the confidence of this threshold value.

Development of the IFC based IDF Converter for Energy Performance Assessment in the Early Design Phase (초기 설계단계 에너지 성능평가를 위한 IFC 기반 IDF 변환기 개발)

  • Kim, In-Han;Kim, Ji-Eun;Choi, Jung-Sik
    • Korean Journal of Computational Design and Engineering
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    • v.16 no.2
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    • pp.146-155
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    • 2011
  • As the seriousness of environmental pollution being on a rise, a low carbon and environment-friendly design for energy efficiency has been issued. With respect to energy in the construction industry, an adoption of BIM which is possible for the various energy performance assessments in the early design phase has been actively working on. In the most cases of energy performance assessment, the data compatibility from the lack of standard software and format became a problem and the improvement for data compatibility system has been needed. This study is to develop the IFC based IDF converter as a middleware which connects between BIM software and energy analysis software. For the building energy performance assessment, Energy Plus and IFC are selected for the standard energy analysis software and its file format. Parameters are organized by steps and the integrated material library is built so it is trying to reduce the existing problem of energy software interface as much as possible. The development of IDF Converter will promote the spread of related fields with increasing the BIM standard and the utilization of energy performance assessment.

Safety and Reliability Assessment by using Dynamic Reliability Analysis Method

  • Lee, Sook-Hyung;Park, Jong-Woon;Lim, Jae-Cheon
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1995.11a
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    • pp.75-81
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    • 1995
  • DYLAM and its related applications are reviewed in detail and found to have many favourable characteristics. Concerning human factor analysis, the study demonstrates that DYLAM methodology represents an appropriate tool to study man-machine behaviour provided that DYLAM is used to model machine behaviour and an appropriate operator interface human factor model is included. A hybrid model which is a synthesis of the DYLAM model, a system thermodynamic simulation model and a neural network predicative model, is implemented and used to analyse dynamically the CANDU pressurizer system.

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Energy-level alignment and charge injection at electrodeorganic interfaces

  • Helander, M.G.;Wang, Z.B.;Lu, Z.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.112-114
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    • 2009
  • Charge injection at electrode-organic interfaces is key to the performance, lifetime and stability of organic electronic devices. The link between fundamental material properties and the energy-level alignment at electrode-organic interfaces will be discussed. In addition the impact of the injection barrier height-a parameterization of the energylevel alignment-on device characteristics will also be discussed.

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PEFP CONTROL SYSTEM USING EPICS

  • Choi HyunMi;Hong In.Seok;Song YoungGi;Cho YongSub
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.656-658
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    • 2005
  • KAERI (Korea Atomic Energy Research Institute) has been performing the project named PEFP (proton engineering frontier project). PEFP has been performing the project of a high power proton accelerator. Control system for 20 MeV proton accelerating structure has developed. We use the EPICS(Experimental Physics and Industrial Control System) tool kit as a foundation of the control system. EPICS is adopted for control systems which have OPI(OPerator Interface) and IOqlnput Output Controller). We have performed the PEPF control system on SUN workstation host computer. In this paper, we present the vacuum monitor, RFQ, and DTL Turbo pump control system.

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