bluuebunny/crossref_metadata_2025_split huggingface dataset:
Precise Control of Poly-Silicon Height by Plasma Etching in FinFET Technology Node
Authors: Wang Yan , Zhang Dongping , Zhang Haiyang 
Published: February 2020

The FinFET technology was brought to mass production for several years to replace the planar transistor structures. Critical process control is highly required for better device and yield performance.[1] When IC scale shrinks, the device performance becomes more and more sensitive to its physical dimension, in which the gate height is included.
In the HKMG era, the metal gate height control can be traced back to the poly-silicon height control, including the wafer-level uniformity, wafer to wafer, and lot to lot. Our work is focused on the poly-silicon height control with plasma etch process. The gate height uniformity control was already reported in 2017 by inductively coupled plasma (ICP) etching process.[2]
In this report, a precise control method from the point view of local height variation within die, surface induced polish process stability and advanced process control of the poly height planarization is discussed by plasma etching process. With an insertion of cap layer, the local poly-silicon height variation can be improved over 40%. A plasma treatment post the cap layer etch-back can reduce the break-through time of poly-silicon process, and thus improve the stability of CMP process as well as the CMP uniformity. An advanced process control of poly-silicon etch back process is implemented. Dynamic process time is dependent on the poly-silicon height post CMP process, which is due to the normal process variation, and 1% of the poly-silicon height variation after poly-silicon etch back is finally realized.
This work was partially sponsored by Shanghai Rising-Star Program (B type). The authors would like to thank Tongxun Guo from Lam research for the support of constructive discussion.

Reference:

[1] C. Auth et al., “A 22 nm high performance and low-power CMOS technology featuring fully-depleted tri-gate transistors, self-aligned contacts and high density MIM capacitors,” in VLSI Symp. Tech. Dig., pp. 131–132, 2012.
[2] Y. Wang et al., “Poly-Si Planarization by ICP Plasma Etch at FinFET Technology”, ECS Trans. 77(3), 71-76, 2017.
(Invited) Nitrogen Functionalization and Doping of Conductive Carbons By Means of Low Temperature Plasmas
Authors: Kovacevic Eva , Boulmer-Leborgne Chantal , Strunskus Thomas , Hussain Shahzad , Jagodar Andrea , von Wahl Erik , Sciaqua Dario , Tatarova Elena , Dias Ana , Cvelbar Uros , Berndt Johannes 
Published: February 2020

Nanomaterials, such as nanocomposites, nanorods, nanotubes and graphenes, are nowadays almost past the title “novel materials”, they have been widely investigated and used as either promising or already proven materials for various applications ranging from electronics and black body coatings to fuel cells and supercapacitors. Such advanced nanomaterials, independently of their chemical composition, are also used for the delivery of therapeutic agents, including biomolecules targeting disease sites, for bioimaging, or in general for biomedical engineering.
This contribution presents several examples of plasma synthesized and plasma functionalized carbon based nanomaterials (nanostructures), CBNs, which nowadays play an important role for biomedical engineering, and in particular for the development of novel biosensors. The examples presented in this paper concern materials which are synthesized in low pressure RF plasmas from hydrocarbon precursors, like ethylene, with or without nitrogen presence during their growth. Most of the examples are vertically aligned graphene flakes. The post-treatment of these materials is performed in low pressure radio frequency capacitively coupled plasma and microwave plasma. In this contribution we will focus on surface treatment by nitrogen and ammonia plasma. The goal of such surface treatments with nitrogen containing plasma is doping and functionalization, very often simultaneously obtained. Plasmas were controlled by means of mass spectroscopy.
The method of choice for the analysis of the bonding situation of the materials before and after treatment in this presentation is near edge X-ray absorption fine structure spectroscopy (NEXAFS), and X ray photoemission spectroscopy (XPS) performed on HESGM beamline, HBZ Bessy II Germany.

Acknowledgments

The authors would like to acknowledge the support obtained by French National Research Agency via projects ANR PlasBioSens and PlasmaBond, APR Apropore, French Regionals support by APR Capt’Eau, and PIVOT. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 730872 (CALYPSO plus for the work at the HZB BESSY II synchrotron, Berlin, Germany) and grant agreement No766894 (FET-OPEN project PEGASUS).
(Invited) Electrophoretic Deposition of Energy Storage Metal Oxides
Authors: Penner Reginald 
Published: February 2020

Electrodeposition is an attractive tool for synthesizing energy storage materials - such as transition metal oxides (TMOs) - for batteries and capacitors. A key advantage of electrodeposition is that the material of interest is synthesized directly on a metal or carbon current collector promoting an intimate, low resistance contact between the deposited material and the current collector. But electrodeposition methods have limited reach if a soluble form of the metal ion does not exist. LixNb2O5 is one technologically important TMO that falls into this category.
The electrophoretic deposition (EPD) process we have developed produces nanoporous, phase pure T-Nb2O5 films 38 nm to 144 nm in thickness. These films exhibit unusually high specific capacities, Csp (units: mAh/g). For example, films of 60 nm thickness produce Csp = 420 mAh/g at 5 A/g and 220 mAh/g at 50 A/g which is to be compared with a theoretical Faradaic capacity of 202 mAh/g. T-Nb2O5 films also produce impressive energy and power with specific energy from 770 - 486 Wh/kg, and specific power in the range from 9-90 kW/kg. It is important to add here that the accuracy of all of these mass-normalized metrics is insured by directly measuring the mass of these films using quartz crystal microbalance (QCM) gravimetry. Our investigation of T-Nb2O5 is still in its early stages, but the exceptional performance seen for these EPD T-Nb2O5 films is very encouraging. Our hypothesis is that EPD provides a general method for the synthesis of energy storage materials with signicant advantages relative to competing methods, including the ability to impart a controllable porosity and the ability to facilitate the enhancement of mechanical and electrical properties via compositing.
In this presentation, I will discuss this EPD process and our recent investigations of the mechanisms of degradation operating in the T-Nb2O5 films prepared using this process. Gold@T-Nb2O5 core@shall nanowires can also be obtained by EPD and the properties of these systems for electrical energy storage will be compared with those of T-Nb2O5 films. Finally, the lithiation/potential-dependent electrical conductivity of solid (non core-shell) T-Nb2O5 nanowires prepared by has been measured for the first time, in-situ. These data, showing variations in electrical conductivity by three orders of magnitude with lithiation state, will also be discussed.
(Invited) Electrodeposited Metallic Nanowires for Bioanalytic Nanofluidic Devices
Authors: Park Sunggook , Podlaha Elizabeth J. , Beheshti Mohammad , Choi Junseo , Li Deyang , Geng Xiaohua 
Published: February 2020

Electrodeposited metallic nanowires have been demonstrated as electrode or sensing materials in many applications such as optoelectronic devices, energy devices, and biosensors due to their excellent electrical and optical properties. However, most of previous demonstrations utilized the metallic nanowires in the form of percolating networks. Individual nanowires also have potential as nanoscale electrodes or nanoscale sensing materials for the applications where electrical signals need to be extracted from nanoscale components of the device. In this sense, metallic nanowires are suitable electrode or sensing materials for bioanalytic nanofluidic devices where electrical signals from nanoscale single molecules need to be interrogated in a device with nanoscale components.
This talk will present strategies and technical challenges to be resolved in applying individual metallic nanowires in bioanalytic nanofluidic devices. While high rate synthesis of metallic nanowires can be achieved via electrodeposition in a nanoporous template, the main challenges to produce nanofluidic devices with individual nanowire electrodes include position and aligning the nanowires at designated locations and cover-plate bonding in the presence of electrode structures. Also, the efforts on device fabrication need to be combined with the effort on engineering nanowires with both sufficient mechanical strength and improved electrical conductivity, so that the nanowires are compatible with both the fabrication and operational protocols. This work is a part of the effort from the NIH Center for BioModular Multiscale Systems for Precision Medicine (CBM2) where the center goal is to design, produce and deliver to the medical community mixed-scale tools for analyzing circulating biomarkers for disease management for precision medicine
Electrodeposition of Bismuth Telluride from a Weakly Coordinating, Non-Aqueous Solution
Authors: Meng Lingcong , Cicvaric Katarina , Bartlett Philip N. , Han Yisong , Hussein Haytham , Sweeney Francis , Kashtiban Reza , Macpherson Julie , Hector Andrew L , Reid Gill , Smith David , Beanland Richard , Groot K. 
Published: February 2020

Thermoelectric materials are of interest for converting waste heat to electricity and could be useful in applications such as power generation.1 Currently, bulk bismuth telluride (Bi2Te3) is the most commonly used material for thermoelectric coolers and waste heat recovery. However, theoretical calculation2 predicts that the thermoelectric performance of Bi2Te3 can be dramatically improved by confining its dimensions to the nanometre scale.
Electrodeposition provides a bottom-up technique compared to conventional coating methods, such as physical vapor deposition (PVD). It is of advantage in the efficient use of the starting material and can be used to plate curved surfaces and even inside of topologically demanding surfaces.3 The use of electrodeposition to fill nano-structures is also achievable, which is exploited in the Damascene process to grow 20 nm diameter Cu wire.4

In electrochemical experiments water is the most commonly used solvent but its limitation includes narrow potential window, which is crucial in electrodeposition as water reduction will be a competing process for metal reduction/deposition and introduces complexity to experiments. Here we employ an electrolyte system based on tetrabutylammonium chlorometallate metal sources with compatible tetraalkyl halide supporting electrolytes in non-aqueous, weakly coordinating solvents,5,6 which provides the ability to deposit alloys with desired structures and properties.
In this work we report the deposition of Bi2Te3 films from dichloromethane. Bi2Te3 is a narrow band gap layered semi-conductor and it is demonstrated that the composition and structure of the BiTe films can be controlled by tuning the electrochemical parameters, such as the electrolyte concentration and deposition potential (Figure 1).7 We then investigate Bi2Te3 nucleation and growth using transmission electron microscopy (TEM) with a boron doped diamond electrode, acting as the electron transparent substrate.8 We observe the initial stage of Bi, Te and BiTe nuclei after electrodeposition (from individual atoms to atom arrays and nanocrystals)
This work is conducted as part of the ADEPT project funded by EPSRC (EP/N035437/1).
[1] Materials 7.4 (2014): 2577-2592. [2] Physical review B 47.24 (1993): 16631. [3] Proceedings of the National Academy of Sciences 106.35 (2009): 14768-14772. [4] IBM Journal of Research and Development 42.5 (1998): 567-574. [5] Chemistry-A European Journal 22.1 (2016): 302-309. [6] RSC Advances 3.36 (2013): 15645-15654. [7] Journal of Electroanalytical Chemistry 839 (2019): 134-140. [8] ACS nano 12.7 (2018), 7388-7396

Figure 1
(Invited) The Electrodeposition of Porous Catalysts for CO2 Reduction
Authors: Ambrozik Stephen , Raciti David , Moffat Thomas P. 
Published: February 2020

Electrocatalytic carbon dioxide reduction exhibits promise as way to combat anthropogenic climate change and convert CO2 into fuels and chemical feedstocks. The efficient reduction of CO2 requires a catalyst that operates at low overpotential, high turnover frequency and high selectivity. Recent trends in state-of-the-art CO2 reduction catalysis involve the utilization of high surface area porous and/or oxide derived catalysts to promote the reduction of CO2 to multi-carbon products. The activity and selectivity of these catalysts has been attributed to a variety of different structural, electronic and geometric aspects ranging from the presence of high energy grain boundaries following oxide reduction1, and residual subsurface oxygen2,3, to cascading reactions coupled with mass transport through the porous catalyst networks4,5,6. This work is focused on examining the effect of high surface area porous catalysts on CO2 reduction. The electrodeposition of high surface area catalysts with well-defined interconnected porosity will be demonstrated and CO2 reduction activity and selectivity will be tested with respect to the catalysts composition, thickness, and pore and ligament size.

References:

1.) Kanan, M. W., Nature
508, 504-507 (2014)
2.) Cuenya, B. R. al, Nature Comm.
7, 1-8 (2016)
3.) Nilsson, A. al, J. Phys Chem. Lett., 8, 285-290 (2017)
4.) Surendranath, Y. al, J. Am. Chem. Soc.,
137, 14834-14837 (2015)
5.) Broekmann, P. al, ACS Catal., 7, 5431-5437 (2017)
6.)Wang, C. al, Catal. Sci. Technol., 8, 2364-2369 (2018)
(Invited) From the Lab to Technical Scale—Aluminum Electroplating from Ionic Liquids
Authors: Gollas Bernhard 
Published: February 2020

After several decades of intense research, room temperature chloroaluminate ionic liquids can now be considered a viable alternative to organic solvent-based alkyl-aluminum electrolytes for the commercial electroplating of aluminum [1]. While their possible use also includes electrochemical energy storage in secondary batteries [2], the development of chloroaluminate ionic liquid electrolytes was initially aimed at surface finishing [3], mainly for corrosion protection of steel. The properties of various combinations of Lewis acidic aluminum halogenides and Lewis basic organic halogenide salts have been established in numerous studies and the reaction mechanism of aluminum electrodeposition and dissolution has been explored, also by modeling [4]. In order to compete with the established SIGAL process [5], various aspects regarding the properties of the electroplated aluminum layers as well as practical issues of the plating process from chloroaluminate ionic liquids have to be addressed.
The morphology and structure of the aluminum layers correlate with their chemical and mechanical properties and must therefore be tailored to the respective application. Here, the current density and bath additives play a major role. Keeping in mind that the Lewis acidity of the electrolyte on the cathode surface has to be maintained, the limiting current can be maximized by adjusting the viscosity through co-solvents or temperature and by agitation of the bath. However, co-solvents as well as increased temperature might compromise the electrolyte stability [6]. Additives can be used as levelers, grain refiners, and/or brighteners. However, the highly reactive Lewis acidic mixture can severely limit their persistence and efficiency [7]. The pre-treatment of the substrate surface must be compatible with the water sensitive electrolyte and directly affects the adhesion of the electroplated layers. In addition, the post-treatment has to be adjusted to the reactive ionic liquid in order to maximize the layer quality.
These issues will be addressed in the talk showing examples from own work. Further aspects such as drag-out loss, bath maintenance, recycling, disposal, and cost, all relevant for a scale-up of the process, will be discussed.
[1] T. Tsuda, G. R. Stafford, and C. L. Hussey, J. .Electrochem. Soc., 164, H5007 (2017).
[2] G.A. Elia, K. Marquardt, K. Hoeppner, S. Fantini, R. Lin, E. Knipping, W. Peters, J.‐F. Drillet, S. Passerini, and R. Hahn, Adv. Mater, 28, 7564 (2016).
[3] F. H. Hurley and T. P. Wier, Jr., J. Electrochem. Soc., 98, 207 (1951).
[4] S. Schaltin, M. Ganapathi, K. Binnemans, and J. Fransaer, J. Electrochem. Soc., 158, D634 (2011).
[5] Y. Zhao and T. J. VanderNoot, Electrochim. Acta, 42, 3 (1997).
[6] P. Kosmus, O. Steiner, W. Goessler, and B. Gollas, Electrophoresis, 35, 1334 (2014)
[7] P. Kosmus, O. Steiner, W. Goessler, B. Gollas, and G. Fauler, Electrophoresis
37, 1095 (2016).
(Invited) Electrochemically Induced Phase Separation in Ionic Liquid Mixtures
Authors: Endres Frank 
Published: February 2020

Liquid-liquid phase separation is mainly dependent on temperature and composition. Electric fields have also been shown to influence demixing of binary liquid mixtures. However, a puzzling behavior that remains elusive is the electric field–induced phase separation in ion-containing solvents at low voltages, as predicted by Tsori and Leibler. Here, we report an experimental study of such a phenomenon in ionic liquid–silane mixtures, which not only results in phase separation at the electrode-electrolyte interface (EEI) but also is accompanied by deposition of porous structures of micrometer size on the electrode. This multiscale phenomenon at the EEI was found to be triggered by an electrochemically induced process. Using several analytical methods, we reveal the involved mechanism in which the formation of new Si–N bonds becomes unstable and eventually decomposes into the formation of silane-rich and silane-poor phases. The deposition of porous structures on the electrode surface is therefore a realization of the silane-rich phase. The finding of an electrochemically induced phase separation not only brings a paradigm shift in understanding the EEI in ionic liquids but also provides alternative strategies toward designing porous surfaces. Further examples like e.g. macroporous conducting polymers will be presented.
reference: Abhishek Lahiri, Niklas Behrens, Giridhar Pulletikurthi, Arik Yochelis, Edwin Kroke, Tong Cui, Frank Endres, Science Advances 26 Oct 2018: Vol. 4, no. 10, eaau9663
DOI: 10.1126/sciadv.aau9663
Treatment of a Highly Concentrated Industrial Effluent with a Pre-Pilot Electrochemical Reactor – Approach to a Practical Application
Authors: García-Rodríguez Orlando , Zhu Si , Olvera-Vargas Hugo , Wang Zuxin , Lefebvre Olivier 
Published: February 2020

Electrochemical advanced oxidation processes (EAOPs) rely on the non-selective and strong oxidant •OH to mineralize organic pollutants in contaminated effluents [1]. Among them, electro-Fenton (EF) has proven efficient and robust for the degradation of recalcitrant organic pollutants [2]. However, most of the studies on EF are limited to reactors with volumes below 1 L and synthetic effluents. Aiming at practical applications, a pre-pilot scale EF reactor is disclosed here with the highest working volume (50 L) among all reports to date. The reactor incorporated commercial BDD or DSA anodes, as well as our patented cathodes , made of carbon fibers coated with graphene. A local company provided us with real wastewater, originating from the fabrication of flat sheet membranes, with an initial TOC of 10,000 ppm and containing hexane, n, n-dimethylformamide (DMF), trimesoyl chloride (TMC), m-phenylene diamine (MPD) and isopropyl alcohol. One of the biggest challenges of scaling up the EF system was to maintain the same efficiency (in terms of mineralization and energy consumption) as in smaller scale laboratory setups. Figure 1A shows the main results at different stages of scaling up the process. The initial lab-scale stage consisted of beaker experiments with a mineralization efficiency of 98% in 24 h. The bench-scale stage, conducted in a specially-designed flow-through recirculated reactor, saw a decrease in mineralization efficiency (36.2%) and an increase in energy consumption (38.4 Wh g-1 of TOC ), which laid the foundations to improve the engineering design of the pre-pilot scale reactor, using a flow simulation CAD software (Fig. 1B). As a result, the energy consumption decreased to 12.8 Wh g-1 of TOC in that final setup and the 24-h mineralization yield attained 64.8%. In conclusion, we demonstrated the successful scale-up of EF for treatment of real industrial wastewater with high organic load, with good mineralization and energy consumption efficiencies.
References
[1] H. Olvera-Vargas, N. Oturan, M.A. Oturan, E. Brillas, Electro-Fenton and solar photoelectro-Fenton treatments of the pharmaceutical ranitidine in pre-pilot flow plant scale, Separation and Purification Technology, 146 (2015) 127-135.
[2] O. Garcia-Rodriguez, Y.Y. Lee, H. Olvera-Vargas, F. Deng, Z. Wang, O. Lefebvre, Mineralization of electronic wastewater by electro-Fenton with an enhanced graphene-based gas diffusion cathode, Electrochimica Acta, 276 (2018) 12-20.

Figure 1
A High Efficiency Osmotic Energy Harvester with Vertically Aligned Boron-Nitride-Nanopore Membrane
Authors: Kim Sangil , Pendse Aaditya , Cetindag Semih , Behura Sanjay , Berry Vikas , Shan Jerry 
Published: February 2020

Application of the abundant salinity-gradients in the environment, motivated by the Gibbs free energy of mixing fresh and salt water, has been under intensive investigation for clean-energy harvesting. Globally, there is a potential of at least 2.6 TW of power that could be generated at coastal estuaries from the ion-concentration gradient. Recent investigation on an energy conversion efficiency of single boron nitride nanotube (BNNT) has revealed the huge potential of an efficient exploitation of electrokinetic phenomena in nanofluidic systems for energy harvesting.
Here, for the first time, we demonstrate rationally designed nanostructured vertically aligned boron-nitride-nanopore membranes (VA-BNNP) which can efficiently harness osmotic power from salinity gradient. A thin hexagonal boron nitride (hBN) layer was uniformly deposited within the pores of anodized alumina substrates by low-pressure chemical vapor deposition which produced first-ever macroscopic VA-BNNP membrane with high nanopore density, up to ~108 pores/cm2. Cross-sectional scanning-electron-microscope (SEM) images show the hBN layer (~35 nm) was uniformly deposited along the pores without excessive hBN on the top surface, ensuring that most pores remained open. In addition, the results of scanning confocal Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) showed the high quality of the hBN layers in the AAO pores. We investigated the power generation of the macroscopic VA-BNNP membranes at different pH and salinity concentrations. The power generation per unit pore area increased as the salt concentration and pH increased. The highest power density of the membrane was up to ~100 W/m2 which is two orders of magnitude higher than that of other macro-scale, salinity gradient driven, power generation system reported so far. In addition, we also elucidate the fundamental ion transport mechanism in BN nanopore using the molecular dynamic simulations to support to the experimental power density values. These findings indicate the great potential of large-area VA-BNNP membranes as next-generation nanostructured membranes for renewable energy harvesting.