bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Ferroelectric Field-Effect Transistors as High-Density, Ultra-fast, Embedded Non-Volatile Memories
Authors: Khan Asif 
Published: November 2022

Ferroelectric field-effect transistors (FEFETs) are receiving significant attention from the microelectronics community for next-generation memory technologies, especially as embedded non-volatile elements for data-centric applications. The main attractive features of FEFETs are that write energy and speed of FEFETs are within an order of magnitude of respective metrics for SRAMs (FEFET ~1 fJ and 1-10 ns vs. SRAM: <1 fJ and <1 ns), all the while requiring a significantly smaller cell size (FEFET 50-60F2 vs. SRAM 120-150F2) and close-to-zero standby leakage power – provided that FEFETs are integrated at the same advanced technology nodes as SRAMs [1]. In this talk, we will discuss the potential path for FEFET toward fulfilling this vision, by addressing the outstanding technological challenges: ultra-fast read-after write, reliability, voltage scaling and variation. To that end, our recent exposition on the trap and reliability physics of FEFETs will highlighted. We will highlight, based on newly developed experimental schemes, how the simultaneous capture and emission of electrons and holes in write cycles occur at the interface and the grain boundaries in the time domain, where in the band-diagram, these traps (acceptors and donors) are located and how exactly they result in the degradation of the read speed and reliability with continued write cycling. Based on these insights, we move on show how engineering the interfacial layer and the ferroelectric grain structure can enable ultra-fast read-after write and write voltage and dramatic improvements in reliability and variation, towards achieving a high-density, ultra-high speed memory technology.
This research is supported by the National Science Foundation, the Defense Advanced Research Program Agency (DARPA), the Semiconductor Research Corporation (SRC) - Global Research Collaboration (GRC) program, the Applications and Systems-Driven Center for Energy-Efficient Integrated Nano Technologies (ASCENT), one of six centers in the Joint University Microelectronics Program (JUMP), a SRC program sponsored by the DARPA, and an Intel Rising Star award.
[1] Mikolajick, T., Schroeder, U. & Slesazeck, S. The past, the present, and the future of ferroelectric memories. IEEE Trans. Electron Devices 67, 1434–1443 (2020).
[2] Asif Islam Khan, Ali Keshavarzi, and Suman Datta. “The future of ferroelectric field-effect transistor technology." Nature Electronics 3.10 (2020): 588-597.
Process Optimization to Reduce Power in HfO2-Based Rram Devices for in-Memory Computing
Authors: Zeinati Aseel , Misra Durga , Triyoso Dina H. , Clark Robert , Tapily Kandabara , Consiglio Steven , Wajda Cory S , Leusink Gert J 
Published: November 2022

Recently, HfO2-based resistive random-access memory (RRAM) devices have shown promise as candidates for in-memory computing applications. By engineering the distribution of defects or oxygen vacancies, the switching dielectric can potentially enable low power switching and multi-conductance levels. A higher concentration of oxygen vacancies closer to the top electrode a two-terminal RRAM device with a HfO2/Al2O3 bilayer structure reduces switching energy (1). Introducing excess oxygen vacancies near the top electrode through a hydrogen plasma treatment with a Ru as top electrode reduces the switching power of the device (2).
In this work we study the pulsed SET operation of different HfO2-based RRAM devices for their possible uses as multi-level cells. We have compared two different RRAM devices with HfO2-based dielectrics. Device-A is prepared with hydrogen plasma treatment at mid-point of HfO2 deposition (10nm Ti/50nmTiN/3nm HfO2(plasma treatment) 3nm HfO2/5nm Ru/5nm ALD TiN/ 50nm PVD TiN). Whereas Device-B constitutes a HfO2/Al2O3 bilayer structure (10nm Ti/50nmTiN/7nm HfO2/1nm Al2O3/5nm Ru/5nm ALD TiN/50nm PVD TiN). Both the devices have Ru as the top metal.
Fig. 1 and Fig. 2 show the conductance modulation obtained by applying successive pulse sequences (80 pulses) with increasing the pulse width tp (from 4 𝜇s to 10 ms) every 20 pulses where the pulse height, Vp, remained fixed at 2V during the experiment. A read pulse with voltage Vr=0.1V and pulse width tr=1ms is applied immediately after each pulse. The forming compliance current in Device-A is seven time lower than Device-B. Both devices clearly show promising behavior of multi-level conductance.

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(Invited, Digital Presentation) Amoeba-Inspired Electronic Computing System for Combinatorial Optimization
Authors: Kasai Seiya , Aono Masashi 
Published: November 2022

A single-celled amoeboid organism is known to maximize nutrient acquisition efficiently by deforming its body (Fig. 1(a)). This ability made it possible for the organism to survive in the harsh natural environment over a billion years. Its sophisticated search capability has been demonstrated by means of the amoeba-based computer in which the amoeboid organism is used to search for a solution of the optimization problem [1]. However, from engineering point of view, the deformation speed of the organism is too slow to compute compared to the modern computers. Here, our idea is to artificially represent the amoeba search capability by electronically mimicking the spatiotemporal dynamics of the organism, which is called “electronic amoeba” (Fig. 1(b)) [2]. We have demonstrated that our system can find a reliable and swift solution to the intractable combinatorial optimization problems including maximum cut problem, satisfiability problem (SAT), and traveling salesman problem (TSP) [3]. In this paper, we show the important features of the amoeba dynamics in terms of the solution search and their electronic representations. We also show how to map the problem to the system, which has a great advantage than the currently available optimization computers called Ising machine.
[1] e.g. L. Zhu, S.-J. Kim, M. Hara, and M. Aono, R. Soc. Open Sci. 5, 180396 (2018). [2] S. Kasai, M., Aono & M. Naurse, Appl. Phys. Lett. 103, 163703 (2013). [3] K. Saito, M. Aono & S. Kasai, Sci. Rep. 10, 20772 (2020).

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(Energy Technology Division Walter van Schalkwijk Award in Sustainable Energy Technology Address) Low Temperature Water Electrolysis as a Near Term Enabler in Climate Change Mitigation
Authors: Ayers Katherine E. , Capuano Christopher , Carmo Marcelo , Deporcellinis Diana , Dalton Luke , Roemer Andy , Motz Andrew R 
Published: November 2022

Generating hydrogen from renewable production methods such as water electrolysis is fundamental to meeting decarbonization goals and mitigating climate change. Regardless of the end market split for hydrogen in ground transportation applications, hydrogen is the major feedstock for industrial chemicals such as ammonia and methanol. The only way to make these processes sustainable is to eliminate carbon dioxide emissions from production of the hydrogen feedstock. Currently, over 95% of this hydrogen is generated from natural gas and other fossil fuels, producing roughly 9 g CO2/g H2. A combination of technologies such as natural gas reforming with carbon capture, utilization and sequestration (CCUS) and water splitting via electrolysis therefore need to be deployed as quickly as possible. In addition, any scheme to convert carbon dioxide to useful chemicals requires a renewable source of hydrogen atoms. So to address both curtailment of ongoing emissions and mitigation of existing CO2 waste streams, renewable hydrogen is a lynchpin for success.
Low temperature electrolysis has commercially deployed for decades, making it one of the only water splitting technologies likely to make an impact in the next 5-10 years. Both liquid alkaline electrolyzers (or alkaline water electrolyzers, AWE) and proton exchange membrane water electrolyzers (PEMWE) have been deployed at >10 MW scale, and many companies are actively working to scale manufacturing to gigawatt capacity. While 2050 goals will likely involve implementation of a broader portfolio of technologies, scaling deployment of existing carbon neutral hydrogen technologies provides the greatest long term benefit by reducing overall emissions earlier. We therefore cannot let “perfect [become] the enemy of good”[1] in terms of waiting for the most efficient, lowest cost solution. At the same time, there are significant improvements that can be made in both AWE and PEMWE products, through advanced materials, processes, and automation. The PEMWE technology in particular can leverage much of the investment in PEM fuel cell research and development, although understanding of electrolysis specific materials and processes in ongoing. This talk will focus on the relationships between material research, process development, and understanding of degradation mechanisms in commercializing reliable technology, and the importance of academia, national labs, and industry to work together in this effort.

[1] Commonly attributed to Voltaire, and others.
Soh Prediction of Li-Ion Batteries with Machine Learning-Based Method
Authors: Choi Jung-goo , Kim Jinwon , Lee Jaeyoung 
Published: November 2022

As fossil fuel-driven society has brought environmental pollution and climate crisis, environmentally friendly alternative energy has been in the spotlight. In particular, electric vehicles receive attention as a next-generation transportation method. The most core technology for electric vehicles is the lithium-ion battery and the battery management system (BMS). However, due to the long lifespan of lithium-ion batteries, it is very time-consuming to measure and improve performance over time. In addition, since the batteries are driven under various conditions, it is not easy to measure the SOC and SOH in real-time because there are many variables. With the recent development of prediction technology through machine learning, it has become possible to predict with high accuracy without complex physical knowledge through high-quality data.
In this study, machine learning technology was applied by utilizing charge/discharge data of lithium ion batteries. The measured values in the initial charge/discharge cycles were selected as independent variable, and the number of cycles remaining until the end of the life was selected as a dependent variable, and then a regression algorithm was applied. After that, model tuning was performed to increase accuracy by reducing overfitting of the data. This study used machine learning technology to predict the SOH of a lithium ion battery with high accuracy with only the initial cycles, thereby contributing to real-time data of BMS and raising the time efficiency of the study.
(Invited, Digital Presentation) ML-Based Fast on-Chip Transient Thermal Simulation for Heterogeneous 2.5D/3D IC Designs
Authors: Chang Norman 
Published: November 2022

Large 3DIC designs with multiple chips require
several iterations of transient thermal analysis particularly for
fine-grain on-chip dynamic thermal management. This requires
a fast thermal analysis technology as opposed to traditional
CFD/FEA based methods which have severe runtime/capacity
limitations for large chips (e.g., 2cmx2cm) in 3DIC while
generating fine grained (e.g., 10umx10um) transient thermal
response. The fast transient thermal analysis is based on the idea
of combining the global, intermediate, and local transient
response curves generated from an ML-predictor. The local,
intermediate, and global transient response curves are scaled
based on the far-field and near-field transient decay surface
components respectively, computed using the trained ML decay
surface predictor, followed by linear superposition of the curves
for each power value in the transient power profile to generate
the effective transient response curve. The runtime for
generating thermal results for a large chip is in the order of
minutes, compared to several hours/days while using CFD/FEA
based tools with good accuracy correlation. The fast transient
thermal solver is implemented on distributed ML computing
platform for parallel computation of transient thermal inference
model.
Cu Deposition on AAO Substrate for Interposer Applications
Authors: Kim Chae Yoon , Kim In Yea , Kim Dong Hyun , Lim Gi hwan , Lee Min-Jeong , Kim Jaehun , Lim Jae-Hong 
Published: November 2022

In recent days, the demand for high-performance devices has increased in the semiconductor industry. These devices require integrated circuits to test out their performance. For this purpose, interposer with both vertical and horizontal copper circuits which offers advanced connections is used. Interposer consists of a substrate material and metal circuits. Common substrate materials for the interposer are silicon and glass. Whereas anodized aluminum oxide (AAO) has less current leakage than silicon substrate, which results in no need for the insulation, and has a vertically self-aligned nanopore structure though wet etching process, which enables high density holes with less cost. AAO was proposed as a substrate material for interposer.
AAO substrate was fabricated using 0.3M oxalic acid solution, followed by fabricating through-hole of AAO. For the interconnection, copper layer was deposited on the surface and hole of AAO substrate by electroless and electrochemical techniques sequentially. Sol-gel catalyst was adopted followed by heat treatment, instead of Sn/Pd catalyzation, to increase the adhesion property and breakdown voltage. Fabricated AAO is a circle shape with 4.8 cm diameter and average pore size is about 98 nm. Cu electroless deposition was performed on AAO with and without through-holes. Thin Cu layer was deposited without voids. The adhesion was measured by SCRATCH TESTER PRO, J&L Tech, Korea, showing first crack around 1.5 N to 2 N. Pulse electrodeposition with surfactant was used to fill the trough-hole of AAO substrate for through-AAO interconnects. The more details will be presented.

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(Invited) Towards the Physical Reliability of 3D-Integrated Systems: Broadband Dielectric Spectroscopic (BDS) Studies of Material Evolution and Reliability in Integrated Systems
Authors: Amoah Papa K. , Sunday Christopher E , Okoro Chukwudi , Ahn Jungjoon , You Lin , Veksler Dmitry , Kopanski Joseph , Obeng Yaw 
Published: November 2022

In this talk, we present an overview of our current research focus in developing non-destructive metrology for monitoring reliability issues in 3D-integrated electronic systems. Working closely with the semiconductor industry, we have been looking at various performance limiting phenomena in 3D-interconnects, the associated dielectrics, and advanced packaging for integrated circuits.
The talk will identify some common reliability concerns, and identify some metrology gaps, for 3-D integrated systems. We will introduce a suite of microwave-based Broadband Dielectric Spectroscopic (BDS) techniques and show how these non-destructive metrologies can serve as early warning monitors for reliability issues. These techniques are based on the application of high frequency microwaves, to probe impedance changes due to material and structural changes in integrated circuits under various external stress. For example, we will also discuss the combination of BDS with scanning probe infrastructure to create the Scanning Microwave Microscopy (SMM) technique, which has been used to detect buried artifacts and characterize metallic contacts. We further illustrate the capabilities of the BDS-based techniques with case studies of three potential reliability issues in 3D IC.
We conclude with a forward look at the future metrology and standards needs 3-D interconnects and the associated advanced packaging.
Enabling High Aspect Ratio 3D NAND Scaling through Deposition and Etch Co-Optimization (DECO)
Authors: Shen Meihua , Hoang John , Chi Hao , Routzahn Aaron , Church Jonathan , Subramonium Pramod Subramonium , Puthenkovilakam Ragesh , Reddy Sirish Reddy , Bhadauriya Sonal , Roberts Sloan , Lill Thorsten , Kamarthy Gowri 
Published: November 2022

Over the past decade, the demands for 3D NAND flash memory devices have been increased tremendously due to ever growing digital economics in consumer electronics, data centers, IOT, healthcare and automotive industries. The growth is further accelerated during the recent Covid period. The industry was able to keep up the scaling roadmap by stacking more memory cell in vertical direction to realize higher bit density at reducing cost per Gig-bit.
Unlike devices scaling via feature size reduction, 3D NAND flash vertical stack scaling puts challenges mostly on film deposition and etch. Among many steps, high aspect ratio (HAR) ONON channel hole formation modules remained the most critical steps. Forming billions of perfect channel holes from top to bottom without distortion and twisting is the grand challenge. Besides individual etch and deposition module optimization, deposition and etch Co-optimization (DECO) could provide new opportunities. In this paper, we will present a summary of the recent progress in the approaches and the benefits of DECO as potential pathways to overcome the HAR ONON patterning. We will discuss the ONON Tier Optimization for profile control to reduce the top bowing and enlarge the bottom CD. We will introduce a sacrificial liner approach to prevent top CD enlargement at deeper etch depth. We will also discuss new mask materials for better etch selectivity and profile control to enable the scaling roadmap.
(Digital Presentation) Importance of Electrified Interfaces in Researchable Metal Anode Batteries: Ionic Liquid Electrolyte Composition and Electrode Preconditioning
Authors: Rakov Dmitrii 
Published: November 2022

Electrode/electrolyte interface is an important part of many electrochemical systems, as its local structure, so called electric double layer (EDL), defines mechanism of charge transfer and stability of the device. Alkaline metal anodes possess high theoretical capacity due to ability of metal-ions to pack in the dense crystal structure, however, their application is rather limited due to formation of dendrites from non-uniform metal deposition and/or poor quality of the interphase. Experimentally, it was found that variation of ionic liquid (IL) electrolyte composition (salt concentration, presence of cosolvent) and applied current density for the formation cycling, i.e., cycling to activate electrode surface before utilisation, significantly affect dendritic growth and stability of metal anode. This presentation aims to show the molecular level relationships between interfacial structure, value of metal deposition potential and the interphase formation with ionic liquid electrolyte of different compositions (salt concentration, presence of cosolvent). Each electrolyte composition results in a particular interfacial metal-ion solvation environment which controls the reductive stability, metal-ion deposition potential, and ultimately the composition and properties the solid-electrolyte interphase (SEI). The latter is dependent on the EDL composition such as the IL cation/metal cation-IL anion ratio or the presence of other surface active additives. Based on this work, our group at Deakin University developed a theoretical framework to choose an optimum current density for the formation cycling of lithium/sodium metal anodes with ionic liquid electrolytes of different composition (salt concentration, presence of cosolvent). Details of these findings are published in following literature [1, 2].
References
1. Rakov Dmitrii A., Chen F, Ferdousi SA, Li H, Pathirana T, Simonov AN, Howlett PC, Atkin R, Forsyth M. Engineering high-energy-density sodium battery anodes for improved cycling with superconcentrated ionic-liquid electrolytes. Nature materials. 2020 May 4:1-6.
2. Dmitrii Rakov, Meisam Hasanpoor, Artem Baskin, John W. Lawson, Fangfang Chen, Pavel V. Cherepanov, Alexandr N. Simonov, Patrick C. Howlett, Maria Forsyth. Stable and Efficient Lithium Metal Anode Cycling Through Understanding the Effects of Electrolyte Composition and Electrode Preconditioning, Chemistry of Materials, 2022, 34, 1, 165–177, https://doi.org/10.1021/acs.chemmater.1c02981
Confocal Fluorescence Microscopy to Probe in Operando electrochemical Conversion
Authors: Graf Anton Marius , Cochard Thomas , Amini Kiana , Rubinstein Shmuel , Aziz Michael 
Published: November 2022

The development of electrochemical devices, such as flow batteries, fuel cells and electrolysers, is critical for the transition to a sustainable economy. Given the critical role of porous electrodes in the performance of these devices, understanding their structure-function relationship is crucial. Although porous electrodes with many different internal structures have been utilized, there is no clear consensus as to what features lead to what aspects of electrode performance. Transport in porous electrodes is commonly approximated by mean-field theories, which assumes a homogenous, Darcy-like permeability in the porous structure. Recent findings have challenged the suitability of these assumptions by revealing extreme heterogeneities in the electrolyte transport, on commercially relevant length scales exceeding the electrode pore size by an order of magnitude. [1]
In this study, we introduce a new analytical method for electrochemical flow devices: 4D Confocal Optical Fluorescence Microscopy. This non-invasive in-situ analytical technique distinguishes between oxidized and reduced molecular species by their fluorescence spectra and maps out 3D molecular concentration fields with single-digit micron resolution (Figure 1). 3D movies, correlated with macroscopic chronoamperometry, add time as a fourth dimension. Thus, electrochemical conversion and species advection and diffusion can be monitored at heretofore unprecedented resolution, giving us new routes to understanding local phenomena in porous electrodes. We demonstrate this method by monitoring the reversible electrolytic reduction of 2,7 anthraquinone disulfonate (AQDS) to its corresponding hydroquinone, H2AQDS, in aqueous electrolyte in a transparent electrochemical cell. We monitor changes in the concentration field as a response to the variation of applied potential and current in real time. We correlate the fluorescence intensity of a particular band of wavelengths to the electrolyte state of charge. Furthermore, high sensitivity to non-linear optical effects enables us to capture the reversible formation of a dimer, specific to the AQDS/H2AQDS system, quantitatively in an operating battery.
This new high-resolution 4D technique of characterizing operando electrochemical devices is expected to provide insight into the relationship between electrode microstructure and electrochemical performance features.
Literature cited:
[1] A.A. Wong, S.M. Rubinstein and M.J. Aziz, “Direct visualization of electrochemical reactions and heterogeneous transport within porous electrodes in operando by fluorescence microscopy” Cell Reports Phys. Sci.
2021, 100388; https://doi.org/10.1016/j.xcrp.2021.100388

Figure 1