bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Electro-Swing Adsorption for CO2 Emissions Mitigation – from Concept to Start-up
Authors: Hatton T. Alan , Voskian Sahag 
Published: September 2023

The increasingly devastating effects of changing climate patterns can be attributed largely to global warming through the continuing accumulation in the environment of anthropogenic greenhouse gases such as carbon dioxide. While reduction of CO2 emissions at relatively concentrated (4-20%) point sources is a crucial component of mitigation strategies for the abatement of the CO2 impact on global temperature rise, it has become increasingly evident that direct removal of accumulated CO2 (at 420ppm, 0.042%) from the environment will also be needed if we wish to limit the global temperature rise by the turn of the century to less that 2°C. Legacy carbon capture processes rely on thermal swings, with elevated temperatures required to break the chemical bonds formed during the cooler capture stage to liberate the CO2 as a pure product stream and regenerate the sorbent. There has recently been a surge of interest in using electrochemically mediated processes for carbon capture and release which can be operated isothermally, are modular, with easy scale out, and can be installed without need for complex heat integration processes. Moreover, they can use renewable and other non-carbon energy resources.
In this presentation, we will trace the development of an electrochemical swing adsorption approach for the capture of CO2, originally conceived in 2015, through to the incorporation of a start-up, Verdox, in 2019 to exploit the technology in both point source and direct air capture applications. This approach exploits the ability of certain redox species, such as quinones, to bind strongly with CO2 when in a reduced state, but which have no affinity for the acid gas when oxidized. The activation by reduction and subsequent de-activation by oxidation of the capture agent can be achieved electrochemically with the redox species either in solution or immobilized on electrode surfaces; it is this latter strategy that we will discuss here. The challenges in electrode development, including the identification and economical synthesis of appropriate redox species for the binding of the CO2, and enhancement of chemical and physical robustness with acceptable uptake kinetics, will be discussed, with projections on the future introduction to industrial applications.
Experimental and Virtual Screening of Phenazine and Phenothiazine Derivatives in Aqueous Solution for Electrochemical Carbon Capture
Authors: Seo Hyowon , Zhang Difan , Hatton T. Alan 
Published: September 2023

Molecular redox-active compounds, including quinone and aza-aromatics, have emerged as tools for capturing carbon dioxide using renewable electricity. Given the vast and highly diverse chemical space of the candidate compounds, accessing their electrochemical properties in a rapid way is attractive for both experimental and virtual screening approaches.
Here we present a study on the experimental screening of a series of commercial redox-active compounds. Phenazine and phenothiazine dyes have been experimentally tested for applications in electrochemical carbon capture, for which they are finding increasing applications as redox mediators due to their unique redox properties in aqueous solution. Nicotinamide has been used as a redox-inactive solubilizing agent to increase the solubilities of general phenazine and phenothiazine derivatives for rapid experimental screening of commercial compounds without time-consuming synthetic modifications. Cyclic voltammetry in aqueous solutions under nitrogen and carbon dioxide indicated reversible behavior in the pH swing of an aqueous solution. Bulk electrolysis experiments demonstrated the chemical stability of phenazine and phenothiazine derivatives. The redox properties and the chemical stability make phenazine and phenothiazine derivatives interesting candidates for future use as redox-active materials in electrochemical carbon capture.
We also present progress towards a virtual screening for the optimization of electrochemical and physicochemical properties of redox-active compounds. Based on our experimental screening of commercial phenazine and phenothiazine compounds identifying neutral red as the lead compound, a virtual screening was performed for optimization of electrochemical and physicochemical properties using machine learning. The virtual screening development steps include (1) chemical library generation using neutral red as a lead compound, (2) molecular property prediction based on quantum chemical calculations, (3) aqueous solubility prediction using machine learning, (4) data processing and database creation, and (5) experimental validation of the optimized compounds for the use of electrochemical carbon capture.

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(Best Paper Award, Invited) Manufacturing of Nanosheets and Multilayer Nanogaps in Silicon
Authors: Lerch Wilfried , Heigl M , Bui-Tran T.X.A , Eisele Ignaz , Merkel R. 
Published: September 2023

Nanogap technology is the basic concept for many promising devices such as localized SOI, multichannel FETs, and resonant tunneling diodes.
It will be shown that intrinsic bulk strain in single crystalline silicon can be used to create homogeneous nanogaps with a few nanometer gap distance. The strain has been created by epitaxial growth of Si1-xGex/Si multi-layer stacks on 200 mm (100) silicon wafers. The stacks were patterned by RIE to reveal the side walls for subsequent lateral etching with gaseous hydrochloric acid. In accordance with former investigations [1] we found that a selectivity up to 1000:1 for Si1-xGex/Si can be achieved for Ge-concentrations >30% and growth temperatures T<650°C. XRD measurements, SEM pictures and wagon wheel test structures prove that for the anisotropic lateral etching behavior intrinsic strain is the dominant factor. Furthermore, the crystal orientation plays a dominant role (Fig. 1). Based on this behavior multilayer nanogaps with spacings <10 nm had been fabricated.
In a subsequent process nanogaps down to 5 nm have been successfully filled completely with dielectrics and/or metals by low temperature (T<450°C) plasma oxidation, LPCVD as well as ALD (Fig. 2). The resulting nanosheets can be used for device applications.
Vertical diodes and lateral MOS transistors with nanogaps and nanosheets have been fabricated. Diodes with a SiO2 gap filling show perfect Fowler-Nordheim tunneling, which proves the high quality of the gap filling process. The electrical properties of nanogap-MOSFETs and various nanogap-diodes will be presented.
[1] Destefanis et al., Semiconductor Sci. Technol. 23, 1 (2008)

Fig. 1: Wagon wheel structure showing the etch anisotropy of 8 nm SiGe layer in Si

Fig. 2: SEM cross section of a multistack of 6 SiGe layers selectively etched and completely filled with LPCVD oxide
(Invited) Improvements in Thermal Budget and Film Properties Using Low Pressure Cure Technology for Advanced 3D Integration Packaging
Authors: Song Kay , Karim Zia , Tan Xinxuan , Bhat Abhishek , Sautter Kenneth , Mingardi A , Vangoidsenhoven D 
Published: September 2023

3D advanced integration with Fan-Out Wafer-Level Packaging (FOWLP) and Fan-Out Panel Level Packaging (FOPLP) offers multiple benefits: heterogenous chip design and stacking, increased interconnect density, and improved performance. However, it also brings new requirements for more compact form factors, low thermal budget materials and processing, and lower cost. The materials, process, and fabrication of heterogenous integration on redistribution layers (RDLs) consisting of metal and polymer dielectrics have become important enablers of the move to advanced packaging applications. To achieve the low-stress and low-cost benefits required by advanced integrated devices, thermal budgets must be reduced throughout the heterogenous integration flow -- including the dielectric curing step, which demands the use of low temperature processing and reduced cure times.
In this presentation, the low temperature and low pressure thermal polymerization of dielectric polyimides used for redistribution layers (RDLs) is reviewed. Specifically, this presentation illustrates the significant impact of the low pressure cure process in reducing temperature (20° to 50° lower) and cure times (up to a 50% reduction) while providing better mechanical (elongation%, tensile strength, Young’s modulus), thermal (TG, Td 1%, Td 5%), and electrical (Dk, Df, dielectric breakdown strength - DBS) properties for different types of dielectric polyimides, including the Fujifilm LTC-9300 series, the Asahi BL-300 series, and the Toray LT-8300 and PW-1500 series. The post-curing polymerization ratio (FT-IR) and film stress were studied and are described. Finally, a proposed mechanism for the described dielectric polyimides’ polymerization under reduced pressure is discussed.
Ongoing developments in design, materials, process and fabrication for FOWLP and FOPLP devices continue to drive progress in 3D heterogenous integration. This study of thermal processing of dielectric polyimides at low pressure and shorter time demonstrates a promising technique to improve overall process flow by reducing thermal budget, stress, and cost.
Low Temperature Wafer Bonding of Silicon Carbide/Aluminum Nitride
Authors: Huang Wei-Chi , Ruan Jian-Long , Kuo Yang-Kuao , Lee Benjamin T.-H. 
Published: September 2023

Because of the wide energy gap material properties and high compatibility with existing silicon material processing, silicon carbide (SiC) has become the preferred material for power management chips that have been used in electric vehicles. On the other hand, aluminum nitride (AlN) material has become the first choice for carrying wafers due to its high strain-resistant mechanical properties, strong dielectric coefficient, excellent thermal conductivity, and high etching resistance. In this study, the surface chemistry of silicon carbide was changed into an AlN-based material to perform wafer bonding processing to develop low-temperature bonding technology for silicon carbide/aluminum nitride materials. We found through experiments that it is quite difficult for a SiC wafer to bond with an AlN wafer even if the surfaces ofthe SiC wafer and the AlN wafer are subjected to conventional surface activation treatment using oxygen plasma or argon plasma. The possible reason is that although the surface of the SiC wafer is bombarded by oxygen or argon plasmas to generate some dangling bonds, the chemical properties of Si-C and Al-N, such as electronegativity, make it difficult to generate chemical bonds between the matching surfaces of SiC/AlN. Through a material modification technology, a high-temperature sputtering method is used to make highly active AlN clusters sputtered from the target directly bond with SiC and finally form a thin AlN layer that strongly adheres to the surface of the SiC wafer. And then through the bonding of AlN/AlN homogeneous materials, although the surface roughness measurement (RMS) cannot satisfy the condition of being less than 5 angstroms for wafer bonding, the goal of low-temperature bonding can be achieved by capillary bonding. Therefore, the SiC surface is changed into an AlN-based thin layer by high-temperature sputtering, which can further chemically bond with the AlN wafer surface by capillary bonding to achieve the low-temperature bonding of SiC/AlN, as shown in Figure 1.
Reference
1. Shao-Ming Nien, Jian-Long Ruan, Yang-Kuao Kuo, and Benjamin Tien-Hsi Lee, Low-temperature rough-surface wafer bonding with aluminum nitride ceramics implemented by capillary and oxidation actions, Ceramics International, Volume 48, Issue 6, 2022

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(Invited) Probing and Utilizing Hot Carriers for Plasmonic Photoelectrochemical Processes
Authors: Park Jeong Young 
Published: September 2023

The detection of hot electrons and understanding the correlation between hot electron generation and surface phenomena are challenging questions in the surface science and catalysis community. Hot electron flow generated on a gold thin film by photon absorption (or internal photoemission) appears to be correlated with localized surface plasmon resonance. It has been found that the hot electron flux generated under photon absorption and exothermic chemical reaction is the major mediator of energy conversion process [1-3]. In this talk, I introduce the research direction to attempt to detect the surface plasmon driven hot carrier at the nanometer scale by using scanning probe microscopy. To detect and utilize the hot electron flows at the macroscale level, the metal-semiconductor nanodiodes were constructed. At the nanometer scale, we utilized photoconductive atomic force microscopy to observe photoinduced hot electrons on a triangular Au nanoprism on n-type TiO2 under incident light. This is the direct proof of the intrinsic relation between hot electrons and localized surface plasmon resonance. We observed surface plasmon induced hot hole by using the system of Au nanoprism on p-type GaN [4]. I will discuss the impact of hot carriers in the photocatalytic activity under photoelectrochemical water splitting by using Au-based plasmonic nanostructures [5].
References
[1] J. Y. Park et al. Chemical Reviews 115, 2781-2817 (2015).
[2] J. Y. Park et al. Accounts of Chemical Research 48, 2475-2483 (2015).
[3] S. W. Lee et al. Surface Science Reports 76 100532 (2021).
[4] H. Lee et al. Advanced Science 7, 2001148 (2020).
[5] K. Song et al. ACS Energy Lett. 6, 4, 1333–1339 (2021).
Rare Earth Doped Lead Zirconate Titanate Thin Films for Memory and Power Device Applications
Authors: Bhattarai Mohan , Morell Gerardo , Katiyar Ram S. 
Published: September 2023

We fabricated thin films of (PbZr0.53Ti0.47)O3 (PZT) and (PbZr0.53Ti0.47)0.90(LaxSc1-x)0.10O3 where; x= 0, 0.2, 0.4, 0.6 and 0.8 denoted as [abbr. PL10x] PL0, PL2, PL4, PL6, and PL8 respectively on the LSMO buffer layer (bottom electrode) by using a PLD technique. The X-ray diffraction peaks show a single-phase perovskite structure of thin films with a preferred (100) orientation that coincides with the MgO and has tetragonal phase symmetry (P4mm). Pt electrodes were deposited at the top of thin films as top electrodes. We achieved higher dielectric permittivity (ε’) for PL0 and PL6 compared to other compositions. We noticed that the role of increasing lanthanum content (decreasing scandium) resulted in the broadening of ε’ with temperature and ferroelectric phase transition decreased to 450 K. However, the scandium doping alone (PL0) didn’t lower the ferroelectric phase transition. We analyzed the temperature-dependent ε’ using the modified Curie-Weiss law. The PL0, PL6, and PL8 thin film capacitors exhibited relaxor ferroelectric properties that were further supported by the Vogel-Fulcher relation.
The P-E hysteresis loops exhibited the role of lanthanum and scandium causing compositional changes in coercive fields. The P-E loops of PZT, PL2, and PL4 exhibited typical ferroelectric features. Whereas, PL0, PL6, and PL8 showed a relaxor ferroelectric behavior which was corroborated by the analysis of the dielectric data. The PL0 and PL6 thin films showed better spontaneous polarization Ps. We achieved superior energy storage performance Ure = 54.63 J/cm3 with η ~ 70% for PL0 and Ure = 26.54 J/cm3 with η ~ 66% for PL8 thin film capacitors. The study demonstrated the idea that by tuning La3+ and Sc3+ the dielectric and ferroelectric properties of thin films can be controlled for suitable electronic applications, such as memory, power devices, and energy storage.
(Invited) Doping of Aluminum Gallium Oxide Alloys
Authors: Wickramaratne Darshana 
Published: September 2023

Designs of electronic devices using aluminum gallium oxide (ALGO) alloys as the barrier layer and gallium oxide (Ga2O3) as the active layer are being considered. The success of these devices is predicated in part on the ability to achieve controlled doping of the ALGO barrier layer. First-principles calculations using hybrid functionals can be instrumental in guiding this effort. I will highlight which dopants can lead to controlled doping in high-Al content ALGO alloys, identify the optimal doping conditions and discuss the impact of the different ALGO polymorphs on this effort.
This work was performed in collaboration with J.B.Varley and J.L. Lyons and was supported by the ONR/NRL 6.1 Basic Research Program.
(Invited) Extraction of Trap Level in GaN Hemt from Transient Current upon Back Gate Voltage Application
Authors: Nishida Kisara , Hoshii Takuya , Wakabayashi Hitoshi , Tsutsui Kazuo , Kakushima Kuniyuki 
Published: September 2023

Gallium nitride (GaN) have attracted attention as a high frequency and high voltage power device material because they have wide bandgap and high mobility [1]. However, large number of defects exists in the epitaxial layer. Current collapse originated from the traps at the surface and in the buffer layer is one of the results of the defects [2]. To distinguish the bulk traps from the whole current collapse, back-gate voltage application is commonly used [3]. In this study, we measured the bulk traps by measuring the drain transient current by back gate voltage application.
TLM pattern (L/W=120/100 mm) was fabricated on an epitaxial wafer; GaN(2nm)/AlGaN(26nm)/ GaN(150/350nm)/C-GaN/buffer/Si sub. Fig. 1 shows the I
d-V
B characteristic of the TLM, where a threshold voltage (V
th) of -300/-450 V can be extracted. A large clock-wise hysteresis suggests large amount of electron trapping in the epitaxial layer. Fig. 2(a) shows the voltage application sequence for measuring the transient I
d 2DEG current. A negatively high V
B below the V
th was applied to clear all the traps initially exists in the epitaxial layers. Then, a step voltage was applied to a certain voltage, and the transient I
d was monitored until the value saturates. Fig. 2(b) shows typical transient I
d on V
B. To analyze the time constant (t) of the transient, the differential of the I
d on logarithm time was used, as the time at the peak signal corresponds to the time constant. Fig. 3(a) shows analysis result, and the peak of this graph correspond to t. On the other hand, the amplitude is related to trap density. Fig. 3(b) shows the Alenius plot of the extracted t, and activation energy from 0.2 to 0.3 eV was detected.
In conclusion, we have measured the transient I
d of GaN-HEMT device with a step voltage application to the substrate back gate. From analysis, we extracted defect levels with activation energy of 0.2 to 0.3 eV. The method is useful for characterizing the trap density in the epitaxial layers.
[1] T. Mizutani, et al., IEEE Trans Electron Devices,
50, 10, 2015 (2003).
[2] G. Meneghesso, et al., IEEE Trans Electron Devices, 53, 12, 2932 (2006).
[3] X. Chen, et al., Appl. Phys. Lett.,
117, 26, 263501 (2020).

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(Invited) implantable and Bioresorbable Chemical Sensors for in-Vivo Real-Time Tracking of Analytes of Clinical Interest
Authors: Barillaro Giuseppe 
Published: September 2023

Imagine your doctor could slip a miniaturized sensing system under your skin and use it to continuously monitor the concentration of almost any molecule in real-time as it circulates through your peripheral blood. This would revolutionize many areas of diagnostics, enabling individualized reports on both disease progression and drug efficacy to be achieved continuously, in real-time. Imagine the sensing system implanted under your skin to communicate with your mobile phone (wireless communication) to transfer the clinically relevant data (biomarker or drug concentration) directly to your doctor. This would impact the way we diagnose diseases and monitor drug efficacy, currently based on single-moment-in-time tests, enabling personal, timely, and effective medical feedback (real-time personalized medicine). Finally, imagine the biochemical sensor in your body is resorbed upon a click, once you don’t need it anymore. This would eliminate any need for sensor retrieval, avoiding risks connected to surgery and providing a risk-free “red button” to destroy it, in case issues will occur (e.g., end of the therapeutic process, inflammation, malfunctioning).
In this lecture, cutting-edge research on the use of bioresorbable nanostructured materials for the development of implantable bioresorbable sensors for analytes of clinical interest (e.g., drugs, biomarkers, ions) in-vivo, in-situ, and in real time that completely dissolve with biologically benign by-products after use will be will reviewed and discussed.
References
A. Paghi, Corsi, A. A. La Mattina, G. Egri, L. Dähne, and G. Barillaro, Wireless and Flexible Optoelectronic System for In-Situ Monitoring of Vaginal pH Using a Bioresorbable Fluorescence Sensor, Advanced Materials Technologies (2022)
M. Corsi, A. Paghi, S. Mariani, G. Golinelli, A. Debrassi, G. Egri, G. Leo, E. Vandini, A. Vilella, L. Dähne, D. Giuliani, and G. Barillaro, Bioresorbable Nanostructured Chemical Sensor for Monitoring of pH Level In Vivo, Advanced Science
, 2202062 (2022). DOI: 10.1002/advs.202202062.
A. A. La Mattina, S. Mariani, G. Barillaro, Bioresorbable Materials on the Rise: From Electronic Components and Physical Sensors to In Vivo Monitoring Systems, Advanced Science, 1902872 (2020). DOI: 10.1002/advs.201902872
Acinetobacter Baumannii Detection Using A Bio-FET Device: Towards Healthcare Infection Management
Authors: Cheng John ChauFu 
Published: September 2023

Acinetobacter is a group of bacteria commonly found in the environment, like in soil and water. While there are many types, the most common cause of infections is Acinetobacter baumannii, which accounts for most Acinetobacter infections in humans.
Acinetobacter baumannii could result in infections in the blood, urinary tract, in wounds of the body or lungs. Traditionally, medical technicians in hospital use the sample from patients (like stool, urine, or sputum) to streak on a plate or do bacteria culture test. It takes too much time and patients cannot wait so long. Therefore, it is vital that a new diagnostic technique can be used to detect Acinetobacter baumannii much faster than the traditional methods.
The electrical double layer (EDL)-gated field-effect transistor-based biosensor (BioFET) is a fast and promising diagnostic technique because it is highly sensitive, quickly response, and high selective to the target analyte. Besides, a portable device could help the medical personnel detect the bacteria and treat the patients as early as possible. Here, we used a portable BioFET device from STARX co. (Model II) to detect the complementary Deoxyribonucleic acid (DNA) of Acinetobacter Baumannii via a specific DNA probe we designed. We utilized the portable device to examine the specificity and selectivity in various conditions, such as urine and blood. Thus, the results showed that the system with the portable device could give the hospital personnel a tool to control healthcare associated infection caused by Acinetobacter baumannii.

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