Chemistry Commons^™

Kinetics, Products, And Brown Carbon Formation By Aqueous-Phase Reactions Of Glycolaldehyde With Atmospheric Amines And Ammonium Sulfate, David O. De Haan, Alyssa A. Rodriguez, Michael A. Rafla, Hannah G. Welsh, Elyse A. Pennington, Jason R. Casar, Lelia N. Hawkins, Natalie G. Jimenez, Alexia De Loera, Devoun R. Stewart, Antonio Rojas, Matthew-Khoa Tran, Peng Lin, Alexander Laskin, Paola Formenti, Mathieu Cazaunau, Edouard Pangui, Jean-François Doussin

Chemistry and Biochemistry: Faculty Scholarship

Glycolaldehyde (GAld) is a C₂ water-soluble aldehyde produced during the atmospheric oxidation of isoprene and many other species and is commonly found in cloudwater. Previous work has established that glycolaldehyde evaporates more readily from drying aerosol droplets containing ammonium sulfate (AS) than does glyoxal, methylglyoxal, or hydroxyacetone, which implies that it does not oligomerize as quickly as these other species. Here, we report NMR measurements of glycolaldehyde’s aqueous-phase reactions with AS, methylamine, and glycine. Reaction rate constants are smaller than those of respective glyoxal and methylglyoxal reactions in the pH range of 3–6. In follow-up cloud chamber experiments, deliquesced …

Understanding Dynamics Of Polymers Under Confinement: A Molecular Dynamics And Neutron Scattering Study, Supun Samindra Kamkanam Mohottalalage

All Dissertations

The current study probes the structure, dynamics, and rheological behavior of associating polymers including ionomers in melts and solutions as well as conjugated polymers confined into nanoparticles, using molecular dynamics (MD) simulations and neutron scattering techniques. The study focuses on two families of associative polymers, ion containing macromolecules and conjugated polymers.

Polymers that consist of ionizable groups along their backbone found uses in a broad range of applications. Examples include light weight energy storage and generation systems, and biomedical applications, where the polymers act as ion exchange membranes, and actuators. The ionic groups tend to form clusters that are in …

Electrodeposition Mechanism And Process Of A Novel Cyanide-Free Gold Sulfite Bath, Jia-Qiang Yang, Lei Jin, Wei-Qing Li, Zhao-Yun Wang, Fang-Zu Yang, Dong-Ping Zhan, Zhong-Qun Tian

Journal of Electrochemistry

A novel cyanide-free gold sulfite process is introduced in this paper. In the bath, chloauric acid was directly employed as the main salt, and hydroxyethylidene diphosphonic acid (HEDP) was used as the stabilizer and coating grain refiner. The bath stability, the gold coating morphology and the mechanism of gold electrodeposition were studied in detail. The results showed that HEDP could significantly improve the bath stability. Moreover, the grains of the gold coating obtained from the gold sulfite bath without HEDP was rod-like, which grew gradually with the increasing of the deposition time, resulting in that the appearance of the coating …

Electrochemical Deposition Of Copper Pillar Bumps With High Uniformity, Bai-Zhao Tan, Jian-Lun Liang, Zi-Liang Lai, Ji-Ye Luo

Journal of Electrochemistry

Electrochemical deposition of copper pillar bumps (CPBs) is one of the key technologies for the advanced packaging. In this study, the effects of the additive concentration, the electrolyte convection, the current density, and the electroplating system on the uniformity of the CPBs have been systematically investigated. The results showed that the profiles of the CPBs were mainly determined by the additive concentration, the bath convection and the current density, while the heights of the CPBs were mainly affected by the electroplating system. For the CPBs profiles, it was found that the low leveler concentration and high current density would generally …

Investigation Of Through-Hole Copper Electroplating With Methyl Orange As A Special Leveler, Jia-Ying Xu, Shou-Xu Wang, Yuan-Zhang Su, Yong-Jie Du, Guo-Dong Qi, Wei He, Guo-Yun Zhou, Wei-Hua Zhang, Yao Tang, Yu-Yao Luo, Yuan-Ming Chen

Journal of Electrochemistry

Methyl Orange (MO) with two kinds of functional groups can act as both an accelerator and an inhibitor, which has been used as a special leveler to simplify the electroplating additive system in the through-hole (TH) copper electroplating experiments. In this work, the role of MO in TH electroplating is characterized by molecular dynamics simulations and quantum chemical calculations. It is suggested that MO can spontaneously flatten the copper surface and be well adsorbed on the cathode surface, which inhibit the copper electrodeposition on the cathode. Electrochemical behavior of MO was evaluated by galvanostatic measurements (GM) and cyclic voltammetry (CV) …

Research Progress In Electroless Cobalt Plating And The Bottom-Up Filling Of Electroless Plating, Yu Shen, Bing-Bing Li, Yi Ma, Zeng-Lin Wang

Journal of Electrochemistry

With the continuous improvement of semiconductor integration, the resistivity of copper interconnect lines increases rapidly. When the width of the interconnect line is close to 7 nm, the resistivity of copper becomes the same as that of cobalt. International Business Machines Corporation (IBM) and Advanced Semiconductor Incorporation (ASI) have used cobalt to replace copper as a next-generation interconnect material. However, the fabrication of the cobalt seed layer and the super filling of electroplating cobalt for the 7 nm via-holes have been still the large challenge. Electroless plating is a very simple method to form a seed layer on the surface …

Research Progress Of Copper Electrodeposition Filling Mechanism In Silicon Vias, Yun-Na Sun, Yong-Jin Wu, Dong-Dong Xie, Han Cai, Yan Wang, Gui-Fu Ding

Journal of Electrochemistry

Aiming at the electroplating filling problem of deep via TSV (through silicon via) interconnection, the multi-compatible integrated manufacturing technology team at the Shanghai Jiao Tong University has completed the numerical solution of the equations and realized the numerical simulation of TSV filling mode by applying the finite element method with arbitrary Lagrange Euler algorithm. The filling mechanisms of blind vias, the butterfly filling form for the through vias and the simultaneous filling mode of vias with different aspect ratios are analyzed by simulation, contributing to the parameter optimization and sample manufacturing. The effects of electroplating current density and heat treatment …

Effect Of Corrosion Inhibitors On Copper Etching To Form Thick Copper Line Of Pcb In Acidic Etching Solution, Xiao-Li Wang, Wei He, Xian-Ming Chen, Hong Zeng, Yuan-Zhang Su, Chong Wang, Gao-Sheng Li, Ben-Xia Huang, Lei Feng, Gao Huang, Yuan-Ming Chen

Journal of Electrochemistry

The chemical compounds of 2-mercaptobenzothiazole (2-MBT), benzotriazole (BTA) and phenoxyethanol (MSDS) as corrosion inhibitors were used to inhibit the copper etching to form the thick copper line of PCB in the acidic etching solution. The inhibition status was characterized with contact angle measurement, electrochemical test and etch factor calculation, while the corrosion morphology of copper surface was studied by scanning electron microscope. The adsorption mechanism of corrosion inhibitors on copper surface is analyzed by molecular dynamics and quantum chemistry calculations. The results indicated that the synergistic function of the two inhibitors could effectively promote their adsorption on the copper surface …

Preface To Special Issue On Electronic Electroplating, Zhi-Dong Chen, Chong Wang, Wei He, Ming Li

Journal of Electrochemistry

No abstract provided.

Mechanism And Application Of Nickel Nano-Cone By Electrodeposition On A Flexible Substrate, Xiu-Ren Ni, Ya-Ting Zhang, Chong Wang, Yan Hong, Yuan-Ming Chen, Yuan-Zhang Su, Wei He, Xian-Ming Chen, Ben-Xia Huang, Zhen-Lin Xu, Yi-Feng Li, Neng-Bin Li, Yong-Jie Du

Journal of Electrochemistry

Nano-array structure possesses promising prospect in power supply, optical device and electronic manufacturing. In this paper, a black nickel nano-cone array was prepared on a flexible substrate by galvanostatic deposition and the corresponding factors involved in the fabrication of nickel nano-cone array was explored. Experimental results showed that a large current density and low main salt concentration were not favored to the formation of cone nickel structure. It was also found that ammonium chloride, as the crystal modifier, was crucial to deposit the uniform nano-cone array. In addition, the growth mechanism of nickel nano-cone was further studied by molecular dynamics …

Electrodeposition Of Functional Epitaxial Films For Electronics, Kui Huang, Rong-Jiao Huang, Su-Qin Liu, Zhen He

Journal of Electrochemistry

Electrodeposition is a solution-based synthesis technique that can be used to fabricate various functional materials on conductive or semiconductive substrates under ambient conditions. Electrodeposition is usually triggered by an artificial electric stimulation (i.e., applied potential/current) to the substrate to oxidize or reduce ions, molecules, or complexes in the deposition solution layer near the substrate surface, which drives this solution layer to depart from its thermodynamic equilibrium and consequently causes the assembly of targeted deposits on the substrate. During electrodeposition, many experimental parameters could affect the properties of the deposits in different ways. To date, many elements (both metals and nonmetals), …

Designing Dynamic And Degradable Polymeric Materials With Thiol-X Chemistries, Reese Sloan

Dissertations

With plastic production poised to increase in coming years, there arises a need to develop new polymeric materials designed to combat the global pollution crisis. A commonly utilized approach in addressing this challenge is to employ a responsive functional moiety into the polymer architecture. Thiol-X reactions, a commonly utilized class of “click” reactions, have garnered broad implementation in new stimuli-responsive materials. This work specifically focuses on utilizing radical-mediated thiol-ene coupling and base-catalyzed thiol-isocyanate reactions to develop a library of ternary thiol-ene/thiourethane covalent adaptable networks (CANs) and hydrolytically labile poly(thioether ketal) thermoplastics. CANs are a class of network materials capable of …

Computational, Synthetic And Spectroscopic Studies On Donor Acceptor Transition Metal Complexes, Ranjana Dangi

Chemistry and Chemical Biology ETDs

Fundamental advances in our ability to design and construct electronic components at the nanoscale will require new design paradigms. One proposed nanoscale electronic component is the molecular rectifier. Molecular and molecule-based electronic components are advantageous due to their ease of synthetic manipulation, and the fact that the size dimensions of molecules are inherently at the nanoscale (0.5 - 3nm). Our group has shown how the Donor-Bridge-Acceptor biradical approach can be used to derive key structure-property relationships that allow insight into the choice of bridge fragments for molecular rectification by using constitutional isomers of the donor-bridge-acceptor biradical (NN-Th-Py-SQ) (S=1/2 ortho-semiquinonate, …

The Photoionization Dynamics, Electronic Spectroscopy, And Excited State Photochemistry Of Alco And Aloc, Vincent J. Esposito, Joseph S. Francisco

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The high cosmic abundance of carbon monoxide (CO) and the ubiquitous nature of aluminum-coated dust grains sets the stage for the production of weakly bound triatomic molecules AlCO (X ²Π) and AlOC (X ²Π) in circumstellar envelopes of evolved stars. Following desorption of cold AlCO and AlOC from the dust grain surface, incoming stellar radiation in the 2–9 eV wavelength range (visible to vacuum ultraviolet) will drive various photochemical processes. Ionization to the singlet cation state will cause an immediate Al–X (X = C, O) bond dissociation to form Al⁺ (¹S) and CO (X ^{1 …}

Evaluation Of The Energetic Factors In Crystalline Pharmaceuticals Using Solid-State Density Functional Theory And Low-Frequency Vibrational Spectroscopy, Margaret P. Davis

Dissertations - ALL

Due to the importance of maintaining stable and effective pharmaceutical solid doses, it is critical to study the variety of solid forms that active pharmaceutical ingredients can adopt including polymorphs, hydrates, and cocrystals. In this work, low-frequency vibrational spectroscopies and rigorous quantum mechanical simulations are combined to provide a new technique for characterizing and investigating pharmaceutically relevant polymorphs, hydrates, and cocrystals as well as a series of model cocrystals. Low-frequency spectra in the sub-200 cm-1 range provide not only unique and characteristic spectra for all of the systems explored here but, along with X-ray structural parameters, they offer a way …

Mechanism Of Sila- And Germafluorenes For Biological Applications, Shelby Jarrett

Dissertations

2,7-disubstituted silafluorenes and germafluorenes, originally designed for OLED applications, are a class of fluorescent dyes that have gained recent interest as probes for bioimaging and as biosensors to monitor cellular dynamics and interactions. Desirable biological probes absorb in the visible region, have high extinction coefficients, high quantum yield and excellent photostability. Here, their spectral properties are investigated under aqueous conditions for relevant biological applications. These molecules display intense blue fluorescence in the solid state and in solution, have high extinction coefficients, and exhibit appreciable solubility in aqueous solution. To better understand potential applications, the mechanism of fluorescence was investigated. It …

Co-Microencapsulation Of Ruellia Tuberosa L. And Cosmos Caudatus K. Extracts For Pharmaceutical Applications, Choirin Annisa, Sasangka Prasetyawan, Anna Safitri

Makara Journal of Science

This study aims to co-microencapsulate the Ruellia tuberosa L. and Cosmos caudatus K. extracts, with chitosan–sodium tripolyphosphate (Na-TPP) as coating material. α-Amylase inhibition and antioxidant assays were conducted to determine the potential of microcapsules used as antidiabetic agents. The microcapsules were manufactured under the influences of pH, Na-TPP concentration, and stirring time. The optimum microencapsulation conditions were selected based on the highest encapsulation efficiency. The optimum microencapsulation conditions were a pH of 4, Na-TPP concentration of 0.15% (w/v), and stirring time of 60 min. The microcapsules exhibited an IC₅₀ (inhibitory concentration) value of 223.64 ± 0.81 µg/mL and an …

Introduction Of Development And Application Technology Of Organic Additives For Acid Copper Electroplating, Hao-Bin Zou, Chao-Li Tan, Wei Xiong, Dao-Lin Xi, Bin-Yun Liu

Journal of Electrochemistry

Acid copper electroplating is one of the key technologies in buildup multilayer PCB (BUM-PCB) manufacture process and the most important technique to achieve electrical interconnection between any layer and high-density interconnection in a substrate. This article introduces the research focus of organic additives used in acid copper electroplating, and developing different kinds of micro-via filling copper electroplating technique applied in various scenarios, and some other technical problems from applications. First of all, according to the chronopotentiometric (CP) experiment results, the levelers with different polymeric molecular structures exhibited various responses of cupric deposition potential along with their increased concentrations, which is …

Study On The Effect Of Additives In The Electrodeposition Of Sn-Ag-Cu Ternary Alloy Solder, Hua Miao, Ming-Rui Li, Wen-Zhong Zou, Guo-Yun Zhou, Shou-Xu Wang, Xiao-Jing Ye, Kai Zhu

Journal of Electrochemistry

Sn-Ag-Cu ternary alloy is the most ideal substitute for Sn-Pb alloy at present, and can be prepared by electrodeposition with high production efficiency, simple equipment, easy maintenance and excellent coating performance. The coordination system of the electroplating solution was investigated through the Hull cell experiment. The type of brighteners used in the plating solution and the ratio of the two brighteners were determined through the microscopic morphologic characterization, electrochemical corrosion test and cathodic polarization curve test. In addition, the dispersant and stabilizer were studied by observing the microscopic morphology and measuring the concentration change of Sn²⁺ ions in the …

Application Of Numerical Simulation Method In Periodic Pulse Reverse Electroplating Through Hole, Yuan-Hang Zhang, Mao-Zhong An, Pei-Xia Yang, Jin-Qiu Zhang

Journal of Electrochemistry

The upgrade of the fifth generation (5G) communication technology increases the number of communication backplane layers and the aspect ratio of through holes on the board, making it more difficult to use traditional direct current deposition for interconnection. Direct current electrodeposition is more prone to uneven coating in the hole, resulting in poor contact between the coating and components, and open circuit. This has a serious impact on the stability of printed circuit board. The periodic pulse reverse plating method can significantly improve the uniformity of high aspect ratio through-hole plating and improve the production quality of through-hole plating through …

Optimization Of Pulse Plating Additives And Plating Parameters For High Aspect Ratio Through Holes, Kai Yang, Ji-Da Chen, Shi-Jin Chen, Wei-Lian Xu, Mao-Gui Guo, Jin-Chao Liao, Zeng-Kun Wu

Journal of Electrochemistry

As an important component in electronic products, printed circuit board (PCB) plays a supporting and interconnecting role for the electronic components in it. With the development of communication technology, electronic products are developing in the direction of “thin, light and small”, and high density interconnection (HDI) comes into being. Due to the high-density interconnection characteristics of HDI boards, the thickness of the board is increasing. At the same time, in order to reserve space for the laying of fine lines on the subsequent board surface, the diameter of the through holes on the board is also decreasing, so the depth-diameter …

An Investigation On The Interface Corrosion Behaviors Of Cobalt Interconnects In Chemical Mechanical Polishing Slurry, Kai-Xuan Qin, Peng-Fei Chang, Yu-Lin Huang, Ming Li, Tao Hang

Journal of Electrochemistry

Cobalt is widely regarded as the most promising interconnect material for 10 nm node and beyond. The development of a chemical mechanical planarization (CMP) slurry suitable for cobalt interconnect is a critical component for the application of cobalt interconnect. During CMP process of the interconnect layer, the achievement of high-quality surface after planarization is greatly challenged by the metal corrosion in CMP slurry. In this contribution, the corrosion behavior of cobalt in a slurry with potassium persulfate (KPS) as an oxidizer, glycine as a complexing agent, and benzotriazole (BTA) as an inhibitor was investigated. Static erosion rates (SER) of cobalt …

Research Progresses Of Cobalt Interconnect And Superfilling By Electroplating In Chips, Li-Jun Wei, Zi-Han Zhou, Yun-Wen Wu, Ming Li, Su Wang

Journal of Electrochemistry

Copper interconnect using dual damascene technology has always been the main means for metallization in the back end of line process. However, with the size effect becoming more and more obvious due to feature size reduction, copper interconnect can no longer meet the demand for high circuit speed in Post-Moore era. Following copper interconnection, cobalt interconnection in chips attracts much attention as an interconnect technology by the next generation, which has been introduced in 7 nm node of integrated circuit manufacturing and below. The electron mean free path of cobalt (~10 nm) is much shorter than copper’s (39 nm), thus …

Electrochemical Sers Study Of Benzotriazole And 3-Mercapto-1-Propanesulfonate In Acidic Solution On Copper Electrode, Yin-Fei Shen, Yan-Li Chen, Sheng-Xu Wang, Ye Zhu, Wen-Chang Wang, Min-Xian Wu, Zhi-Dong Chen

Journal of Electrochemistry

Since the development of acid copper plating technology, the role of additives is indispensable. In addition to the main salt copper sulfate and supporting electrolyte sulfuric acid, suppressors, accelerators, levelers and chlorine ions (Cl^-) are also required to be added into the plating solution. Appropriate additive system can have a significant impact on the coating or the plating solution, which can help improve the quality of the coating and increase the brightness of the coating. Through electrochemical measurement, vibrational spectroscopy, scanning probe microscopy, molecular dynamics simulation and other methods, researches have a deeper understanding in the adsorption configuration …

Development Status Of Copper Electroplating Filling Technology In Through Glass Via For 3d Interconnections, Zhi-Jing Ji, Hui-Qin Ling, Pei-Lin Wu, Rui-Yi Yu, Da-Quan Yu, Ming Li

Journal of Electrochemistry

With the slow development of Moore's Law, the high density and miniaturization of microelectronic devices put forward higher requirements for advanced packaging technology. As a key technology in 2.5D/3D packaging, interposer technology has been extensively studied. According to different interposer materials, it is mainly divided into organic interposer, silicon interposer and glass interposer. Compared with the through silicon via (TSV) interconnection, the through glass via (TGV) interposer has received extensive attention in the 2.5D/3D advanced packaging field for its advantages of excellent high-frequency electrical characteristics, simple process, low cost, and adjustable coefficient of thermal expansion (CTE). However, the thermal conductivity …

Influences Of Suppressing Additive Malachite Green On Superconformal Cobalt Filling And Nucleation, Xiao-Chuan Ma, Ya-Qiang Li, Pei-Xia Yang, Jin-Qiu Zhang, Mao-Zhong An

Journal of Electrochemistry

As the semiconductor integrated circuits evolve into 7 nm technology and beyond, the resistance of the Cu filling at back-end-of-line interconnects no longer linearly scales with dimension. The metal Co with lower mean free path can be used to replace Cu for reducing the line resistance caused by the scattering on the outer surface and grain boundary in the smaller and smaller size. In this study, CoSO₄ was used as the main salt, boric acid as a buffer and malachite green (MG) as an inhibitor for further research. According to the electrochemical cyclic voltammetric (CV) curves by using a …

Study On Low Voltage Electrodeposition Of Diamond-Like Carbon Film, Li Wang, Min-Xian Wu, Jun Li, Yan-Li Chen, Wen-Chang Wang, Zhi-Dong Chen

Journal of Electrochemistry

Diamond-like carbon (DLC) films are receiving a lot of attention from the scientific community, thanks to the promise of DLC films for applications in microelectronics and optoelectronics. Usually, electrodeposition is the preferred common technique because of low cost, large deposition area and simplicity of the setup. However, when carbon films are electrodeposited on a stainless steel, high cell voltages (≥1000 V) are required owing to the low electric conductivity of the organic solvents. This work has developed a new electrolyte system that could achieve carbon deposition on a stainless steel under a low applied cell voltage. The DLC films were …

Study On Weak Alkaline Cyanide-Free Silver Plating Process For Etching Lead Frame, Jian-Wei Zhao, Hai-Feng Zhu, Xiao-Hui Yu, Gui-Yun Yuan, Zhi Sun

Journal of Electrochemistry

As a new development direction of integrated circuit chip carrier, etched lead frame has been gradually applied in microelectronics industry in recent years. Since the preparation of the etched lead frame requires the use of multiple layers of non-alkali-resistant photoresist films with specific patterns, and the traditional cyanide silver plating is unable to meet this requirement, making that the development of weakly alkaline cyanide free silver plating process has great significance. In this paper, a weak alkaline silver plating process based on 5,5-dimethylhydantoin (DMH) cyanide-free silver plating system was studied. The electrodeposition behavior of the system and the nucleation mechanism …

Effect Of Sodium Alcohol Thiyl Propane Sulfonate On Electrolysis Of High Performance Copper Foil For Lithium Ion Batteries, Sen Yang, Wen-Chang Wang, Ran Zhang, Shui-Ping Qin, Min-Xian Wu, Naotoshi Mitsuzaki, Zhi-Dong Chen

Journal of Electrochemistry

Electrolytic copper foils have been widely used in printed circuit boards and lithium-ion batteries due to their simple production process and high economic value. In the process of electrolysis foil making, additives can greatly improve the performance of electrolytic copper foils. In this work, the copper foils were prepared in a self-designed plate electrodeposition device of which the operating principles were in accordance with those of actual industrial production. A series of the Virgin Make-up Solution (VMS: 312.5 g·L^-1 CuSO₄·5H₂O, 100 g·L^-1 H₂SO₄, 50 mg·L^-1 Cl^-) containing …

Microstructure Of Electrodeposited Copper Foil: Discussion On The Mechanism Model Of Three-Dimensional Electrocrystallization, Ren-Zhi Liu, Ping-Ling Xie, Chong Wang

Journal of Electrochemistry

The manufacturing of electrolytic copper foil has attracted more and more attention with the extensive applications of printed circuit board and lithium battery. The industrial scale is still extending. Compared with the developments of electroplating equipment and electroplating process, there is limited research on the mechanism of electrodeposition. This paper summarizes the manufacturing process of electrodeposited copper foil and analyzes the differences of various electroplating parameters in different electrodeposited copper technologies, and points out the important role of electrodeposition current density in the formation of copper foil. By showing and comparing the microstructures of different electrodeposited copper foils, the influences …