scholarly journals Performance Degradation of Nanofilament Switching Due to Joule Heat Dissipation

Electronics ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 127
Author(s):  
Mohammad Shah Al-Mamun ◽  
Marius K. Orlowski
Keyword(s):  
Cross Talk ◽  
Heat Dissipation ◽  
Memory Cell ◽  
Performance Degradation ◽  
Joule Heat ◽  
Electrical Performance ◽  
Temperature Sensitive ◽  
Thermal Reliability ◽  
Crossbar Array ◽  
The Impact

When a memory cell of a Resistive Random Access Memory (ReRAM) crossbar array is switched repeatedly, a considerable amount of Joule heat is dissipated in the cell, and the heat may spread to neighboring cells that share one of the electrode lines with the heat source device. The remote heating of a probed memory cell by another cell allows separating the influence of temperature effects from the impact of the electric field on the resistive switching kinetics. We find that the cell-to-cell heat transfer causes severe degradation of electrical performance of the unheated neighboring cells. A metric for the thermal degradation of the I–V characteristics is established by a specific conditioning of a so-called “marginal” device used as a temperature-sensitive probe of electrical performance degradation. We find that even neighboring cells with no common metal electrode lines with the heated cell suffer substantial electrical performance degradation provided that intermediate cells of the array are set into a conductive state establishing a continuous thermal path via nanofilaments between the heated and probed cells. The cell-to-cell thermal cross-talk poses a serious electro-thermal reliability problem for the operation of a memory crossbar array requiring modified write/erase algorithms to program the cells (a thermal sneak path effect). The thermal cross-talk appears to be more severe in nanometer-sized memory arrays even if operated with ultra-fast, nanosecond-wide voltage/current pulses.

scholarly journals Thermal and Chemical Integrity of Ru Electrode in Cu/TaOx/Ru ReRAM Memory Cell

2019 ◽  
Vol 8 (12) ◽  
pp. N220-N233
Author(s):  
Mohammad Al-Mamun ◽  
Sean W. King ◽  
Marius Orlowski
Keyword(s):  
Memory Cell ◽  
Operating Conditions ◽  
Electrical Performance ◽  
Pt Electrode ◽  
Switching Performance ◽  
Inert Electrode ◽  
Work Function Difference ◽  
The Impact ◽  
Si Wafer

A good candidate for replacing the inert platinum (Pt) electrode in the well-behaved Cu/TaOx/Pt resistive RAM memory cell is ruthenium (Ru), already successfully deployed in the CMOS back end of line. We benchmark Cu/TaOx/Ru device against Cu/TaOx/Pt and investigate the impact of embedment of Cu/TaOx/Ru on two different substrates, Ti(20nm)/SiO2(730nm)/Si and Ti(20nm)/TaOx(30nm)/SiO2(730nm)/Si, on the cell's electrical performance. While the devices show similar switching performance at some operating conditions, there are notable differences at other operation regimes shedding light on the basic switching mechanisms and the role of the inert electrode. The critical switching voltages are significantly higher for Ru than for Pt devices and can be partly explained by the work function difference and different surface roughness of the inert electrode. The poorer switching properties of the Ru device are attributed to the degraded inertness properties of the Ru electrode as a stopping barrier for Cu+ ions as compared to the Pt electrode. However, some of the degraded electrical properties of the Ru devices can be mitigated by an improved integration of the device on the Si wafer. This improvement is attributed to the suppression of crystallization of Ru and its silicidation reactions that take place at elevated local temperatures, present mainly during the reset operation. This hypothesis has been corroborated by extensive XRD studies of multiple layer systems annealed at temperatures between 300K and 1173K.

Performance Degradation Due to Nonlocal Heating Effects in Resistive ReRAM Memory Arrays

MRS Advances ◽  
2019 ◽  
Vol 4 (48) ◽  
pp. 2593-2600 ◽  
Author(s):  
M. Al-Mamun ◽  
M. Orlowski
Keyword(s):  
Heat Dissipation ◽  
Heat Exposure ◽  
Memory Cell ◽  
Performance Degradation ◽  
Conduction Path ◽  
Pt Electrode ◽  
Heating Effects ◽  
Frequent Switching ◽  
Intermediate Cells ◽  
Nonlocal Heating

ABSTRACTFrequent switching of resistive memory cell may lead to a local accumulation of Joules heat in the device. Since the ReRAM cells are arranged in crossbar arrays with the two electrodes running perpendicular to each other, the heat generated in one device spreads via common electrode metal lines to the neighboring cells causing their performance degradation. Also cells that do not share any of the two electrodes (e.g. the diagonal array cells) with the hot device may also degrade provided the intermediate cells are set to an on-state establishing thus a continuous thermal conduction path between the heated and the probed device. It is found that the heat conduction along the active Cu electrode is more pronounced than that along the inert Pt electrode. Devices with Rh inert electrode performed better than those with Pt electrode due to better heat conductivity properties of Rh vs Pt. The heat dissipation is also found worse for a heated device with narrow and thin lines causing, however less degradation of more distant neighbor cells than for wide and thick metal lines. Finally, there is a trade-off between dissipating the heat quickly form the heated device to increase its maximum switching cycles and the heat exposure of the neighboring devices.

scholarly journals Pre-Emphasis Pulse Design for Random-Access Memory

Electronics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1454
Author(s):  
Yoshihiro Sugiura ◽  
Toru Tanzawa
Keyword(s):  
Time Constant ◽  
Random Access ◽  
Memory Cell ◽  
Random Access Memory ◽  
Memory Access ◽  
Access Time ◽  
Access Memory ◽  
Delay Times ◽  
Cell Current ◽  
The Impact

This paper describes how one can reduce the memory access time with pre-emphasis (PE) pulses even in non-volatile random-access memory. Optimum PE pulse widths and resultant minimum word-line (WL) delay times are investigated as a function of column address. The impact of the process variation in the time constant of WL, the cell current, and the resistance of deciding path on optimum PE pulses are discussed. Optimum PE pulse widths and resultant minimum WL delay times are modeled with fitting curves as a function of column address of the accessed memory cell, which provides designers with the ability to set the optimum timing for WL and BL (bit-line) operations, reducing average memory access time.

Are neutrophil extracellular traps the link for the cross-talk between periodontitis and rheumatoid arthritis physiopathology?

Rheumatology ◽  
2021 ◽  
Author(s):  
Sicília Rezende Oliveira ◽  
José Alcides A de Arruda ◽  
Ayda Henriques Schneider ◽  
Valessa Florindo Carvalho ◽  
Caio Machado ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Cross Talk ◽  
Neutrophil Extracellular Traps ◽  
Periodontal Therapy ◽  
Clinical Parameters ◽  
Extracellular Traps ◽  
Early Ra ◽  
The Cross ◽  
High Concentrations ◽  
The Impact

Abstract Objectives Neutrophil extracellular traps (NETs) play a role in the pathogenesis of periodontitis and rheumatoid arthritis (RA). However, it remains poorly understood whether NETs participate in the cross-talk between periodontitis and RA. Herein, we investigated the production of NETs in individuals with periodontitis and RA and its association with clinical parameters. The impact of periodontal therapy on RA and NET release was also assessed. Methods The concentration of NETs and cytokines was determined in the saliva and plasma of individuals with early RA (n = 24), established RA (n = 64), and individuals without RA (n = 76). The influence of periodontitis on the production of NETs and cytokines was also evaluated. Results Individuals with early RA had a higher concentration of NETs in saliva and plasma than individuals with established RA or without RA. Periodontitis resulted in an increase in the concentration of NETs of groups of individuals without RA and with early RA. The proportion of individuals with high concentrations of IL-6, IL-10 and GM-CSF was higher among individuals with periodontitis than among individuals without periodontitis. The concentrations of TNF-α, IL-6, IL-17/IL-25, and IL-28A were particularly high in individuals with early RA. Worse periodontal clinical parameters, RA onset and RA activity were significantly associated with circulating NETs. Periodontal therapy was associated with a reduction in the concentration of NETs and inflammatory cytokines and amelioration in periodontitis and RA. Conclusion This study reveals that NETs are a possible link between periodontitis and RA, with periodontal therapy resulting in a dramatic switch in circulating NET levels.

Electrical-Thermal-Reliability Co-Design for TSV-Based 3D-ICs

2015 ◽  
Author(s):  
Tiantao Lu ◽  
Ankur Srivastava
Keyword(s):  
Mechanical Stress ◽  
Electrical Performance ◽  
Mechanical Reliability ◽  
Thermal Reliability ◽  
Conduction Path ◽  
Placement Problem ◽  
Thermal Profile ◽  
3D Ic ◽  
3D Ics ◽  
Simulation Based

This paper presents an electrical-thermal-reliability co-design technique for TSV-based 3D-ICs. Although TSV-based 3D-IC shows significant electrical performance improvement compared to traditional 2D circuit, researchers have reported strong electromigration (EM) in TSVs, which is induced by the thermal mechanical stress and the local temperature hotspot. We argue that rather than addressing 3D-IC’s EM issue after the IC designing phase, the designer should be aware of the circuit’s thermal and EM properties during the IC designing phase. For example, one should be aware that the TSVs establish vertical heat conduction path thus changing the chip’s thermal profile and also produce significant thermal mechanical stress to the nearby TSVs, which deteriorates other TSV’s EM reliability. Therefore, the number and location of TSVs play a crucial role in deciding 3D-IC’s electrical performance, changing its thermal profile, and affecting its EM-reliability. We investigate the TSV placement problem, in order to improve 3D-IC’s electrical performance and enhance its thermal-mechanical reliability. We derive and validate simple but accurate thermal and EM models for 3D-IC, which replace the current employed time-consuming finite-element-method (FEM) based simulation. Based on these models, we propose a systematic optimization flow to solve this TSV placement problem. Results show that compared to conventional performance-centered technique, our design methodology achieves 3.24x longer EM-lifetime, with only 1% performance degradation.

Bio-inspired Passive Skin Cooling for Handheld Microelectronics Devices

2012 ◽  
Vol 134 (1) ◽  
Author(s):  
Zhi Huang ◽  
Xinsheng Zhang ◽  
Ming Zhou ◽  
Xiaoding Xu ◽  
Xianzheng Zhang ◽  
...  
Keyword(s):  
Heat Dissipation ◽  
Handheld Devices ◽  
Solution Temperature ◽  
Passive Cooling ◽  
Temperature Sensitive ◽  
Operation System ◽  
Critical Solution Temperature ◽  
Handheld Device ◽  
Skin Cooling ◽  
Cooling Technology

Increasing functionality demands more heat dissipation from the skin of handheld devices. The maximum amount of heat that can be dissipated passively, prescribed by the natural convection and blackbody radiation theories, is becoming the bottleneck. In this letter, we propose a novel bio-inspirited technique that may overcome this passive cooling limit. It is made possible by using a biomimetic skin capable of perspiration on demand. The key component of the biomimetic skin is a thin layer of temperature sensitive hydro gel (TSHG). The TSHG layer can sweat the skin with moisture when the skin temperature is higher than the TSHG’s lower critical solution temperature (LCST), and thus boost the heat dissipation rate through evaporation. The TSHG layer can absorb moisture at low temperature to replenish. With this novel passive cooling technology, a handheld device can have nearly four times more power beyond the traditional passive cooling limit, and may be powerful enough to run a desktop operation system like a full functional personal computer.

Design of Optimum Plate-Fin Natural Convective Heat Sinks

2003 ◽  
Vol 125 (2) ◽  
pp. 208-216 ◽  
Author(s):  
Avram Bar-Cohen ◽  
Madhusudan Iyengar ◽  
Allan D. Kraus
Keyword(s):  
Nusselt Number ◽  
Specific Heat ◽  
Rectangular Plate ◽  
Heat Sink ◽  
Heat Dissipation ◽  
Thermal Design ◽  
Heat Sinks ◽  
And Performance ◽  
Nusselt Number Correlation ◽  
The Impact

The effort described herein extends the use of least-material single rectangular plate-fin analysis to multiple fin arrays, using a composite Nusselt number correlation. The optimally spaced least-material array was also found to be the globally best thermal design. Comparisons of the thermal capability of these optimum arrays, on the basis of total heat dissipation, heat dissipation per unit mass, and space claim specific heat dissipation, are provided for several potential heat sink materials. The impact of manufacturability constraints on the design and performance of these heat sinks is briefly discussed.

scholarly journals Modeling of Photovoltaic Module Using the MATLAB

2019 ◽  
Vol 9 ◽  
pp. 59-69
Author(s):  
Alok Dhaundiyal ◽  
Divine Atsu
Keyword(s):  
Standard Test ◽  
Electrical Performance ◽  
Photovoltaic Module ◽  
Solar Pv ◽  
Pv Module ◽  
Proposed Model ◽  
Current Voltage ◽  
Pv Modules ◽  
The Impact ◽  
The Mathematical Model

This paper presents the modeling and simulation of the characteristics and electrical performance of photovoltaic (PV) solar modules. Genetic coding is applied to obtain the optimized values of parameters within the constraint limit using the software MATLAB. A single diode model is proposed, considering the series and shunt resistances, to study the impact of solar irradiance and temperature on the power-voltage (P-V) and current-voltage (I-V) characteristics and predict the output of solar PV modules. The validation of the model under the standard test conditions (STC) and different values of temperature and insolation is performed, as well as an evaluation using experimentally obtained data from outdoor operating PV modules. The obtained results are also subjected to comply with the manufacturer’s data to ensure that the proposed model does not violate the prescribed tolerance range. The range of variation in current and voltage lies in the domain of 8.21 – 8.5 A and 22 – 23 V, respectively; while the predicted solutions for current and voltage vary from 8.28 – 8.68 A and 23.79 – 24.44 V, respectively. The measured experimental power of the PV module estimated to be 148 – 152 W is predicted from the mathematical model and the obtained values of simulated solution are in the domain of 149 – 157 W. The proposed scheme was found to be very effective at determining the influence of input factors on the modules, which is difficult to determine through experimental means.

A comprehensive review on the impact of nanofluid in solar photovoltaic/thermal system

2021 ◽  
pp. 095440622110556
Author(s):  
E Manikandan ◽  
K Mayandi ◽  
M Sivasubramanian ◽  
N Rajini ◽  
S Rajesh ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Physical Properties ◽  
Energy Resource ◽  
Green Energy ◽  
Electrical Performance ◽  
Solar Photovoltaic ◽  
Solar Pv ◽  
The Impact ◽  
Thermo Physical Properties ◽  
T System

Solar energy is a major renewable energy resource used in power production, heating processes, and other applications such as domestic and industrial utilization. It is an abundant form of green energy. Different techniques have been made for energy conversion and one among them is solar photovoltaic/thermal (PV/T) system. Unfortunately, the greatest cause of concern is the rise in temperature of solar PV cells, which will have a negative effect on electrical performance. Thereby, eliminating excess heat on PV cells with heat transfer fluids to lower the temperature of the cells can improve electrical efficiency. A nanofluid is a promising heat transfer fluid to effectively enhance the system efficacy compared with conventional fluids. As the nanoparticle size is very small, the surface area of the nanoparticle is large so it enhances the heat transfer rate. Thereby, recently it has taken on a new dimension for research studies to enhance its thermal behavior for engineering application. This review paper discusses about the importance of nanofluid in solar PV/T system and advantages of employing nanofluid in PV/T system which has high thermo-physical properties. Nanoparticle and nanofluid preparation methods were presented. The thermo-physical properties like thermal conductivity, viscosity, density, and specific heat capacity were also discussed.

Methodology to Quantify Impact of Package Delamination on Performance of High-Side Smart Power Switch Design

2020 ◽  
Vol 2020 (1) ◽  
pp. 000015-000020
Author(s):  
Min Chu ◽  
Jie Chen ◽  
Abidur Rahman ◽  
Rajen Murugan
Keyword(s):  
Electrical Performance ◽  
Diagnostic Feature ◽  
Electromagnetic Modeling ◽  
Smart Power ◽  
Modeling Methodology ◽  
Power Switch ◽  
High Side ◽  
Die Attach ◽  
Power Switches ◽  
The Impact

Abstract Generally, IC packages with exposed pads have excellent thermal and electrical performance – assuming high fidelity and integrity of die attach material. However, reliability challenges associated with die attach impacts electrical performance of vertical power FETs for high-side power switches. As such, it is critical to quantify the impact of these challenges on high-side power switches operation, so that their protection and diagnostic feature circuitries can be properly designed for mission critical applications. In this paper we present on a package and PCB co-modeling methodology that was developed to assess impact of die attach integrity on performance of high-side power switch designs. We explain how electrical co-optimization of the system (viz. FET-Package-PCB) interactions, was achieved through a coupled circuit-to-electromagnetic modeling, simulation, and analysis methodology. Silicon laboratory measurements data that validate the modeling methodology will be presented.

Sign in / Sign up

Export Citation Format

Share Document