The Experts below are selected from a list of 149469 Experts worldwide ranked by ideXlab platform
Jiyan Dai - One of the best experts on this subject based on the ideXlab platform.
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Memory effect of an organic based trilayer Structure with au nanocrystals in an insulating polymer matrix
Nanotechnology, 2010Co-Authors: P F Lee, Jiyan DaiAbstract:The Memory effects of gold (Au) nanocrystal (NC) non-volatile Memory Structures consisting of polyvinylpyrrolidone (PVP) K-30 polymer tunneling and control layers are investigated. The trilayer Structure (PV P/Au-NCs + PV P/PV P) on p-type Si substrate was fabricated by spin coating, and transmission electron microscopy study reveals that the average size of the Au-NCs formed is about 5 nm in diameter. Capacitance–voltage (C–V) measurement on the Memory Structure shows a counter-clockwise hysteresis loop with a significant flat band voltage shift, revealing a Memory effect of the Au-NCs with a charge density of up to 1 × 1012 cm − 2 and a flat band voltage shift of 2.0 V. A unique feature of the double loop in the C–V curves suggests double barriers during electron tunneling. The I–V hysteresis is also characterized, and a switching mechanism of resistive change is discussed.
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study of tunneling mechanism of au nanocrystals in hfalo matrix as floating gate Memory
Applied Physics Letters, 2008Co-Authors: K C Chan, P F Lee, Jiyan DaiAbstract:A floating gate Memory Structure containing HfAlO control gate, self-organized Au nanocrystals (NCs), and a HfAlO tunnel layer has been fabricated by pulsed-laser deposition. Owing to the charging effects of Au NCs, a significant threshold voltage shift has been obtained and the Memory window up to 10.0V and stored charge density up to 1×1014∕cm2 has been achieved. Fowler–Nordheim tunneling mechanism is used to analyze the capacitance-voltage characteristics of the trilayer Memory Structure, and it is found that higher density and smaller size of the Au NCs result in a higher tunneling coefficient and a larger Memory window.
W K Choi - One of the best experts on this subject based on the ideXlab platform.
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hafnium aluminum oxide as charge storage and blocking oxide layers in sonos type nonvolatile Memory for high speed operation
IEEE Transactions on Electron Devices, 2006Co-Authors: W K Chim, W K ChoiAbstract:The charge storage and program/erase mechanisms in polysilicon-oxide-nitride-oxide-silicon (SONOS) Memory Structures with charge-storage layers of different materials are investigated in this paper. In particular, the use of a HfAlO charge-storage layer in a SONOS-type Memory Structure is proposed. Compared to other high-/spl kappa/ charge-storage layers, HfAlO has the advantage of high-speed program/erase of HfO/sub 2/ as well as the good charge-retention time of Al/sub 2/O/sub 3/, which makes HfAlO a promising candidate for the charge-storage layer in a SONOS-type Memory. The use of HfAlO with different HfO/sub 2/ and Al/sub 2/O/sub 3/ compositions as a blocking-oxide layer in SONOS-type Structures is also investigated.
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conductance voltage measurements on germanium nanocrystal Memory Structures and effect of gate electric field coupling
Applied Physics Letters, 2006Co-Authors: W K Chim, W K ChoiAbstract:Conductance-voltage (G-V) analyses were performed on trilayer germanium (Ge) nanocrystal Memory capacitor Structures, consisting of a high dielectric constant (high-κ) layer (5nm thick) grown on silicon, a sputtered Ge middle layer (4nm thick), and a 20nm thick sputtered cap oxide layer (either SiO2 for moderate gate electric field coupling or HfAlOx for better electric field coupling). Comparisons of the G-V characteristics were performed with a control capacitor sample without nanocrystals. The distinctive characteristics due to nanocrystals could be separated and identified from the interface traps provided the Memory Structure has sufficiently high electric field coupling from the gate applied voltage, resulting in a large electric field across the tunnel dielectric layer. This work attempts to provide an explanation to the G-V characteristics under the following three conditions: (1) interface trap dominated, (2) nanocrystal dominated, and (3) a combination of effects from both interface traps and na...
W K Chim - One of the best experts on this subject based on the ideXlab platform.
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hafnium aluminum oxide as charge storage and blocking oxide layers in sonos type nonvolatile Memory for high speed operation
IEEE Transactions on Electron Devices, 2006Co-Authors: W K Chim, W K ChoiAbstract:The charge storage and program/erase mechanisms in polysilicon-oxide-nitride-oxide-silicon (SONOS) Memory Structures with charge-storage layers of different materials are investigated in this paper. In particular, the use of a HfAlO charge-storage layer in a SONOS-type Memory Structure is proposed. Compared to other high-/spl kappa/ charge-storage layers, HfAlO has the advantage of high-speed program/erase of HfO/sub 2/ as well as the good charge-retention time of Al/sub 2/O/sub 3/, which makes HfAlO a promising candidate for the charge-storage layer in a SONOS-type Memory. The use of HfAlO with different HfO/sub 2/ and Al/sub 2/O/sub 3/ compositions as a blocking-oxide layer in SONOS-type Structures is also investigated.
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conductance voltage measurements on germanium nanocrystal Memory Structures and effect of gate electric field coupling
Applied Physics Letters, 2006Co-Authors: W K Chim, W K ChoiAbstract:Conductance-voltage (G-V) analyses were performed on trilayer germanium (Ge) nanocrystal Memory capacitor Structures, consisting of a high dielectric constant (high-κ) layer (5nm thick) grown on silicon, a sputtered Ge middle layer (4nm thick), and a 20nm thick sputtered cap oxide layer (either SiO2 for moderate gate electric field coupling or HfAlOx for better electric field coupling). Comparisons of the G-V characteristics were performed with a control capacitor sample without nanocrystals. The distinctive characteristics due to nanocrystals could be separated and identified from the interface traps provided the Memory Structure has sufficiently high electric field coupling from the gate applied voltage, resulting in a large electric field across the tunnel dielectric layer. This work attempts to provide an explanation to the G-V characteristics under the following three conditions: (1) interface trap dominated, (2) nanocrystal dominated, and (3) a combination of effects from both interface traps and na...
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over erase phenomenon in sonos type flash Memory and its minimization using a hafnium oxide charge storage layer
IEEE Transactions on Electron Devices, 2004Co-Authors: Yanny Tan, W K Chim, Byung Jin Cho, Weekiong ChoiAbstract:The over-erase phenomenon in the polysilicon-oxide-silicon nitride-oxide-silicon (SONOS) Memory Structure is minimized by using hafnium oxide or hafnium aluminum oxide to replace silicon nitride as the charge storage layer (the resulting Structures are termed SOHOS devices, where the "H" denotes the high dielectric constant material instead of silicon nitride). Unlike SONOS devices, SOHOS Structures show a reduced over-erase phenomenon and self-limiting charge storage behavior under both erase and program operations. These are attributed to the differences in band offset and the crystallinity of the charge storage layer.
Luis Calvo - One of the best experts on this subject based on the ideXlab platform.
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context nodes in the operation of a long term Memory Structure for an evolutionary cognitive architecture
Genetic and Evolutionary Computation Conference, 2017Co-Authors: Richard J Duro, J A Becerra, Juan Monroy, Luis CalvoAbstract:This paper describes the creation and use of context nodes, or Cnodes, as an integral part of the Structure of a network based Long Term Memory that has been constructed within the Multilevel Darwinist Brain cognitive architecture. Context nodes are networks with multiplicative inputs that support the storage of context related information, that is, a Cnode relates the world the system is in, as well as the system's goal and current state, to the most adequate policy to operate in this context in terms of its previous experience. These Structures provide a simple, yet very effective way of retrieving (or activating) long term Memory or experience based information when part of a context is detected. A simple example of the operation of the Long Term Memory using Cnodes is presented and discussed.
Yoed N Kenett - One of the best experts on this subject based on the ideXlab platform.
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a semantic network cartography of the creative mind
Trends in Cognitive Sciences, 2019Co-Authors: Yoed N Kenett, Miriam FaustAbstract:The role of semantic Memory in creativity is theoretically assumed, but far from understood. In recent years, computational network science tools have been applied to investigate this role. These studies shed unique quantitative insights on the role of semantic Memory Structure in creativity, via measures of connectivity, distance, and Structure.
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remotely close associations openness to experience and semantic Memory Structure
European Journal of Personality, 2018Co-Authors: Alexander P. Christensen, Katherine N Cotter, Yoed N Kenett, Roger E Beaty, Paul J SilviaAbstract:Openness to experience—the enjoyment of novel experiences, ideas, and unconventional perspectives—has shown several connections to cognition that suggest open people might have different cognitive processes than those low in openness. People high in openness are more creative, have broader general knowledge, and show greater cognitive flexibility. The associative Structure of semantic Memory might be one such cognitive process that people in openness differ in. In this study, 497 people completed a measure of openness to experience and verbal fluency. Three groups of high (n = 115), moderate (n = 121), and low (n = 118) openness were created to construct semantic networks—graphical models of semantic associations that provide quantifiable representations of how these associations are organized—from their verbal fluency responses. The groups were compared on graph theory measures of their respective semantic networks. The semantic network analysis revealed that as openness increased, the rigidity of the semantic Structure decreased and the interconnectivity increased, suggesting greater flexibility of associations. Semantic Structure also became more condensed and had better integration, which facilitates open people’s ability to reach more unique associations. These results were supported by open people coming up with more individual and unique responses, starting with less conventional responses, and having a flatter frequency proportion slope than less open people. In summary, the semantic network Structure of people high in openness to experience supports the retrieval of remote concepts via short associative pathways, which promotes unique combinations of disparate concepts that are key for creative cognition.
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how semantic Memory Structure and intelligence contribute to creative thought a network science approach
Thinking & Reasoning, 2017Co-Authors: Mathias Benedek, Yoed N Kenett, Miriam Faust, Konstantin Umdasch, David Anaki, Aljoscha C NeubauerAbstract:ABSTRACTThe associative theory of creativity states that creativity is associated with differences in the Structure of semantic Memory, whereas the executive theory of creativity emphasises the role of top-down control for creative thought. For a powerful test of these accounts, individual semantic Memory Structure was modelled with a novel method based on semantic relatedness judgements and different criteria for network filtering were compared. The executive account was supported by a correlation between creative ability and broad retrieval ability. The associative account was independently supported, when network filtering was based on a relatedness threshold, but not when it was based on a fixed edge number or on the analysis of weighted networks. In the former case, creative ability was associated with shorter average path lengths and higher clustering of the network, suggesting that the semantic networks of creative people show higher small-worldness.