Engineering Commons^™

Interfacial Electrochemical Behavior Of Fibrinogen On Pt Electrode, Song-Mei Chen, Jian-Zhang Zhou, Zhong-Hua Lin, Dong-Mei Zeng, Nan Huang, Guo-Jiang Wan

Journal of Electrochemistry

The interfacial electrochemical behaviors of fibrinogen on Pt electrode in phosphate buffered solution(PBS) was investigated by using cyclic voltammetry and electrochemical in-situ FTIR spectroscopy.The cyclic voltammetry results demonstrated that the fibrinogen adsorb on Pt electrode and impede the interfacial charge transfer of hydrogen ion reaction process as well as of oxygen reduction process,which is increased with higher scan rate.The cyclic voltammetry spectra of platinum absorbed with fibrinogen in K₃[Fe(CN)₆] and K₄[Fe(CN)₆]·3H₂O solutions shows that the fibrinogen can partly decrease the oxidation and reduction current peaks.There is no specific anodic and …

Molten Salt Treatment Of Mno2 And Investigation On Supercapacitor Properties, Ye Chen, Zun-Bo Zhang, Wei Zhang, Liang Liu, Zhi-Min Liu

Journal of Electrochemistry

The MnO₂ prepared by solid phase method is treated by KCl-NaCl-LiCl molten salt system.The XRD patterns indicated that the crystal structures of MnO₂ sample have had the α-MnO₂ and γ-MnO₂ phase,the crystallinity of sample is increased after treated by molten salt.The electrochemical properties were tested by cyclic voltammetry,constant current charge/discharge and AC impedance.The result shows that the supercapacitor performance of the treated material has improved.The specific discharge capacitance of the treated sample are 129.07 F·g^-1,increased by 27.88% compared to 100.94 F·g^-1 of untreated sample.Long cycle life and high coulombic efficiency were also demonstrated …

Potentiometric Response Of Glucose On Mno2-GoX Carbon Paste Electrode, Cai-Juan Wang, Xiao-Ya Hu

Journal of Electrochemistry

A novel carbon paste electrode(CPE) modified with MnO₂ and glucose oxidase(GO_x), is reported. Different factors, such as the effect of supporting electrolyte, pH of solutions,various paste glues, the amount of MnO₂ and temperature, which may influence the determination of H₂O₂ and glucose were tested to optimize. Based on above, potentiometric determination of glucose was achieved in neutral solution and at 35 ℃, the electrode gave a response of 36.12～34.62 mV/pG lucose between 2.0×10^-5 mol·L-1 and 5.2×10^-3 mol·L^-1 with a detection limit of 3.3×10^-6 mol·L^-1. Moreover, this kind …

Square Wave Stripping Voltammetric Behaviors Of Rutin On Glassy Carbon Electrode And Its Application, Jun Hua, Xiao-Ying He, Fang Liao, Qing-Tao Zhu

Journal of Electrochemistry

The electrochemical behaviors of rutin(Rt) at glassy carbon electrode were studied by square wave stripping voltammeter in the presence of 0.1mol·L^-1HAc-NaAc buffer solution(pH=3.0).The sensitive oxidation peak of rutin was observed and which potential peak is 0.46V(vs.SCE).The experimental parameters,such as pH value,deposition potential and deposition time were investigated and selected.The peak currents were proportional to the concentration of rutin in range of 5.0×10^-8 mol·L^-1~1.0×10^-6mol·L^-1,and the linear regression coefficient equaled 0.99799,the detection limit was 1.1×10-8 mol·L^-1.This method was applied to the determination of rutin content in tablet with satisfactory results.

Corrosion Electrochemical Behavior Of Az31 And Az61 Magnesium Alloys In Simulated Sea Water, Ling-Jie Li, Sheng-Hai Yu, Jing-Lei Lei, Chuan-Pu Liu, Sheng-Tao Zhang, Fu-Sheng Pan

Journal of Electrochemistry

Tafel polarization curves and electrochemical impedance spectroscopy(EIS) techniques were employed to investigate the corrosion electrochemical behavior of AZ31 and AZ61 magnesium alloys.Scanning electron microscopy(SEM) was used to observe the alloy microstructure and corrosion morphology.The variation of the bulk corrosive medium pH with immersion time was recorded during the exposure of the alloys to simulated sea water.Results show that AZ61 magnesium alloy exhibits much better anti-corrosion ability than AZ31 magnesium alloy.The different corrosion behavior between the two magnesium alloys is correlated with their different content of Al alloying element.The higher content of Al in AZ61 alloy leads to the homogenerous microstructure …

The Determination Of Vitamin C By Bromophenol Blue Modified Glassy Carbon Electrode, Shu-Lin Zhang, Min-Jiao Li, Yi Luo, Xiao-Bo Wang

Journal of Electrochemistry

The content of ascorbic acid of(vitamin C) was analyzed by using fast cyclic voltamment with bromophenol blue(BPB) modififed GC-electrode,and which experimental conditions were optimiged.The results showed that the BPB modified GC-electrode had the good stability and anti-jamming faculty for analysing the content of ascorbic acid.A linear relationship between the peak current and concentration of vitamin C in the range of 0.0050~0.1500 g·L^-1 was obtained,which related coefficient and the detection limit are-0.9991 and 0.0010 g·L^-1,respeclively.The method has satisfactory results.

Effects Of Oxidation Methods On The Stability Of Coooh Conductive Network In Foam Nickel Electrodes, Xiao-Feng Li, Yan-Wei Wei, Hui-Chao Dong

Journal of Electrochemistry

Two kinds of the cobalt oxyhydroxide conductive networks in foam nickel electrodes were prepared by different methods i.e.the electrochemical-oxidation(EO) and chemical-oxidation(CO) and which redox behaviors were studied by using cyclic voltammetry and X-ray diffraction measurements.The results show that the CoOOH(CO) has better redox reversibility than CoOOH(EO) and the structure of the former can be kept when nickel electrodes are subjected to a negative potential.Thus,98.7% capacity retention is demonstrated on nickel/metal-hydride batteries with CoOOH(CO) conductive network after being imposed over-discharge state storage;on the contrary,only 83.3% capacity retention is found on the batteries with CoOOH(EO) conductive network.

The Influence Of The Sputtering Power On The Structural And Electrochemical Properties Of Tin Oxide Films, Min-Zhen Cai, Jie Song, Ming-Sen Zheng, Qi-Hui Wu, Sun-Tao Wu, Quan-Feng Dong

Journal of Electrochemistry

Tin oxide films were deposited on silicon substrates at room temperature using the radio frequency(RF) magnetron sputtering with different sputtering power.The influence of sputtering power upon the crystal structure,surface morphology and electrochemical properties of tin oxide films were then investigated.The XRD and SEM results illustrate that the phase of tin oxide thin films changed from amorphous to crystalline and the grain size augments with the increase of the sputtering power.The constant current charge and discharge cycle tests imply that the initial irreversible capacity loss of Li/tin oxide batteries increase and which capacity decrease as the sputtering power increases.The sputtering power …

Effect Of Au At Different States On Electrocatalytic Performance Of Pd Catalyst For Oxidation Of Formic Acid, Xin Wang, Ya-Wen Tang, Tian-Hong Lu

Journal of Electrochemistry

Using liquid-reduction or complex-redution method,four catalysts,i.e,the Au/C,Pd/C,Pd-Au/C-T and Pd-Au/C-H were preparated and which electroanalytic activities and stabilities for the oxidation of formic acid were compares.It was found that the Au/C catalyst has no electrocatalytic activity,and the Pd/C catalyst possesses the good electrocatalytic performance for the oxidation of formic acid.The addition of Au into the Pd/C catalyst can increase the electrocatalytic activity and stability.Especially,the electrocatalytic activity and stability of the Pd-Au/C-T catalyst with the alloy of Pd and Au are better than that of the of the Pd-Au/C-H catalyst,in which,Pd and Au do not form the alloy.The investigation of its reason …

In Situ Measurement Of Chloride Concentration And Ph Distribution In The Crevice During The Crevice Corrosion Of Copper Electronic Board, Min Zhang, Xiang-Dong Zhuo, Chang-Jian Lin

Journal of Electrochemistry

Although the crevice corrosion of metals had been extensively studied in the past years,it remained lack of direct experimental information of the micro chemical environments and electrochemical conditions inside the corroding crevice.The distribution of chloride concentration and local pH in the occluded area are the most crucial factors in development of crevice corrosion.The array probes in one dimension of Ag/AgCl and IrO₂ array were developed in this work to in situ follow the distribution of chloride concentration and local pH in the occluded area during the crevice corrosion propagation.Based on a designed simulated crevice corrosion system in 0.5mol/L NaCl …

Synthesis Of 2,2′-Dichlorohydrazobenzene Using An Ion Exchange Membrane, Chao Zhang, Pei-Jin Li

Journal of Electrochemistry

Using an ion exchange membrane as a separator,the 2,2′-Dichlorohydrazobenzene is synthesized by the electrolytic reduction of o-chloronetrobenzene.The effects of electrode activation condition,current density,electrolyte temperature on electrolytic reduction are discussed.It was found that the optimum reaction temperature is 80 ℃.When the electrolyte concentration was 30% NaOH at the anode and 10% NaOH at the cathode,current density is 4.2A/dm²,the current efficiency reached 73% and yield is 83%.

Bs News

Building Services Engineering

No abstract provided.

Measurements Of 11B(P,P)11B And 11B(P,Alpha)8Be With Polarized Protons, Thomas Lewis

The Corinthian

The vector analyzing powers, Ay(theta, E), of the 11B(p,p)11B and 11B(p,alpha)8Be reactions were measured as a function of angle and energy as a part of a program to study the reaction 11B(p,alpha)2alpha. The experiment was performed at the Triangle Universities Nuclear Laboratory at Duke University, where the polarized proton beams between 100 nA and 600 nA with energies (Ep) of 2.65, 3.9, 4.0, 5.11, and 5.5 MeV were produced using the ABPIS source and the FN tandem. These energies were selected to be on (and off) several of the known resonances in this region. The target was composed of 35 …

Investigation Of Microplasma Cells Fabricated On Silicon Wafer, Koffi Abalo-Akuvi

Journal of the Microelectronic Engineering Conference

The objective of this project was to investigate the possibility of producing array of microplasma, having aluminum and silicon electrodes, and oxide as a dielectric with cavity size as large as 30x30 μm². One of the potential applications among many was to use such device as a photodector. A new class of photodectors, hybrid semiconductor-microplasma devices, to exhibit photoresponsivities in the visible and near infrared that are more than an order of magnitude larger than those typical of semiconductor avalanche photodiodes [1]. After fabrication processing, the route causes of failure were determined. Processing problems were diagnosed and …

Theoretical Study And Device Modeling Of Iii-V Nanostructured Photovoltaics, Ryan Aguinaldo

Journal of the Microelectronic Engineering Conference

A methodology for the modeling and theoretical analysis of novel nanostructured photovoltaic devices is presented in this work. The nanostructures in consideration are quantum wells and quantum dots composed of 111-V materials. Their incorporation into the space charge region of an otherwise conventional solar cell is presented as a means to increase photovoltaic energy conversion efficiency. The enhancement for both single- and multi-junction solar cells is also outlined. Limitations of the available models are briefly discussed. Analyzed results allow for the further optimization of these novel devices.

Developing An Empirical Model For Tunable Porosity In Porous Nanocrystalline Silicon Membranes, Jon-Paul S. Desormeaux

Journal of the Microelectronic Engineering Conference

In this study, a new process for the fabrication of porous nanocrystalline silicon (pnc-Si) membranes is proposed, and the early stages in the development of an empirical, stressbased model for tunable porosity are revealed. Pnc-Si membranes that were fabricated by the proposed process showed substantial improvements in membrane morphology, i.e., porosity and pore uniformity across the wafer. These improvements were assumed to be related to stress, as suggested by the addition of materials that differ in Young’s Modulus and in coefficients of thermal expansion. In order to explore this assumption, stress measurements were conducted via stylus trace on a Tencor …

Deep Submicron Pattern Formation For Selective Epitaxial Growth Of Ii-V Semiconductors, Kenny Fourspring

Journal of the Microelectronic Engineering Conference

In the world of optoelectronics a common barrier has been integrating logic and device circuits on a single substrate, as it was generally only possible to optimize the device for the logic, or the optoelectronic device at hand. However, a new approach that uses metal organic chemical vapor deposition (MOCVD) enables the growth of Ill-V semiconductors on silicon substrates. The fact that 111-V semiconductors can now be integrated within the current silicon CMOS processes may allow new possibilities. An approach to investigate the feasibility of this process has been investigated. The enabler to integrate HI-V is an innovative approach called …

Fabrication Of Metal-High-K Capacitors On Germanium (May 2008), Rahul K. Gupta

Journal of the Microelectronic Engineering Conference

The objective of this study is to gain understanding of MOS devices built on germanium. Ge PMOS transistors were simulated using Silvaco. MOS capacitors have been fabricated using hafnium oxide, a high-K dielectric, and molybdenum, a metal gate. The capacitance-voltage (CV) characteristics of the devices were obtained and studied. During the deposition of hafnium oxide on germanium substrate, the surface integrity plays a significant role. Two different surface treatments for the Ge substrates were implemented: one with NH₃ immersion at 650°C for one minute, the other with a deionized (DI) water rinse for one minute. In doing so, one …

Fabrication Of An Esaki Tunneling Diode By Proximity Rapid Thermal Diffusion, Sankar Krishnan

Journal of the Microelectronic Engineering Conference

Tunnel diodes need degenerately doped junction to optimum performance. They are fabricated using the Molecular Beam Epitaxial method. This method yields good degenerately doped junctions. However it is not clear whether the process can be used with 300 mm wafer technology due to the demand for a high thermal budget. Proximity Rapid Thermal Diffusion (PRTD) uses the RTP tool for its thermal processing. The amount of time used for the processing is in seconds which yields to a low thermal budget. Moreover RTP tools are a common place in the industry and hence comparatively, PRTD is easy to integrate into …

Double Patterning Technique Using An Aluminum Hardmask, Brian Lindenau

Journal of the Microelectronic Engineering Conference

The goal of this project was to successfully demonstrate a double patterning technique using equipment available at the SMFL at RIT. Traditional methods of increasing resolution have been essentially exhausted; therefore new methods of increasing resolution are needed. One of these new methods is double patterning, which splits a dense pattern into two less dense patterns which are imaged in two steps, thereby reducing imaging constraints. Overall a proof of concept of the double patterning process was achieved. Imaging of 0.5 μm drawn features was demonstrated, resulting in 0.3 μm post-etch.

Process Development For The Fabrication Of A Double-Sided Photodiode, Kimberly E. Manser

Journal of the Microelectronic Engineering Conference

Given a cross-section and functionality requirements for a photodiode designed for application as the focal plane array on SNAP (SuperNova Acceleration Probe), a proposed satellite in the Joint Dark Energy Mission by NASA and the DOE, a process has been developed to fabricate the device in the most efficient and reliable manner. The photodector is to be hybridized with a ROIC (Read-Out Integrated Circuit) that interprets the individual pixel signals and converts the electrical information into an image. After several versions of the process based on simulations, efficiency of sequence, and research, a test run of key process steps was …

Three Dimensional Nanochannel Formation By Reflective Interference Lithography, Michael Many

Journal of the Microelectronic Engineering Conference

An imaging technique using TM polarized illumination at 45 degree incidence to a highly reflective surface has been demonstrated possible. The imaging technique was able to produce a single row of over exposed nanochannels. Further experimentation will be required to develop a stable process where multiple rows of channels can be formed. Once the optimal process is determine, experimentation can be designed to create either or both photonic crystal structures and a pitch doubling technique.

Germanium Esaki Diodes By N-Type In-Situ Doping, Amy Miller

Journal of the Microelectronic Engineering Conference

A rapid melt growth process is performed in the formation of Esaki tunnel junctions on in-situ n-doped germanium on silicon substrates. An aluminum-silicon alloy is used as the p-dopant for the junctions as well as an ohmic contact for testing. The rapid thermal anneal (RTA), used for the incorporation of the aluminum-silicon, is characterized by varying ramp rate and peak anneal temperatures. It is found that peak anneal temperature is the dominant factor affecting the current density through the devices. The maximum current density recorded is 2098mA/cm2 at a peak anneal temperature of 620°C.

Active Matrix Polymer Cholesteric Liquid Crystal Display (May 2008), G B. Myhre, J P. Cox, K L. Marshall, T Z. Kosc, C A. Fromem, S D. Jacobs

Journal of the Microelectronic Engineering Conference

Polymer cholesteric liquid crystal display technology has been demonstrated previously on single pixel monolithic displays at the University of Rochester’s Lab for Laser Energetics. Mass reorientation of PCLC flakes in a variety of host fluids has been modeled and observed. However, a pixilated PCLC display has never been demonstrated. The motive of the project was to create a prototype pixilated PCLC display in order to demonstrate the commercial viability of the technology. An active matrix back plane was designed, fabricated, tested, and incorporated with the existing PCLC display technology. The resulting display showed strong isolation between pixels with negligible cross …

Integrated Thin Film Crystalline Silicon Photoactive Components, Isaac Onigman

Journal of the Microelectronic Engineering Conference

Single crystal silicon photoactive devices using a low-temperature thin-film transistor (TFT) compatible process were designed and manufactured on bulk silicon and silicon-on-insulator (SOT) substrates at the Semiconductor and Microsystems Fabrication Laboratory (SMFL) at RIT. Photodiodes and phototransistors designed with transparent indium-tin oxide (ITO) gates, along with n-type and p-type ITO Schottky test devices were manufactured and investigated. Possible applications for devices investigated here include ondisplay photodetectors, on-display digital logic and possible integration into touchscreen or lightpen sensitive liquid crystal TFT displays.

The photoactive devices were integrated in active pixel sensor (APS) arrangements to determine feasibility of integration into large-field SOT …

Reclaimed Silicon Solar Cells, Victor Prajapati

Journal of the Microelectronic Engineering Conference

Fully processed CMOS Si wafers were reclaimed to make solar cells, while ensuring an acceptable efficiency loss of 15%. This project successfully developed a wafer reclaim process coupled with a solar cell fabrication process. The optimum efficiency obtained was 12.4% using prime wafers and surface texturing, while comparably processed reclaimed wafers were able to achieve 10.5% efficiency.

Thermal Sio2 Growth Rate Enhancement At Low Temperature Using An Nf3 Additive, Ryan D. Rettmann

Journal of the Microelectronic Engineering Conference

Thermally grown silicon oxide growth enhancement using small amounts of NF₃ was investigated, examining both growth rate and interface quality. Low temperature results showed noted growth rate enhancement at temperatures above 7000 C. Interface quality showed significant improvement. Further enhancement is expected through modified chamber and equipment design.

Fabrication Of Thermally Actuated Micromirror Using Cmos Compatible Surface Mems Process With Xef2 Release Etch, Christopher G. Shea

Journal of the Microelectronic Engineering Conference

Thermally actuated micromirrors were fabricated to demonstrate a CMOS compatible surface micromachined MEMs process that was developed. A key step in the process was the used of a XeF₂ etch to release the structures. A design was created that varied key factors including mirror pad size and number of anchors. For the smallest pads attached by a single anchor, the length and width was varied. The release etch was found to require a sacrificial layer of greater than one micron for fest lateral undercutting. Mirrors with the longest and narrowest necks were found to display the greatest deflection.

Process Characterization For Integration Of Esaki Diodes Into Aspect Ratio Trapping Material, Stuart A. Sieg

Journal of the Microelectronic Engineering Conference

A process for forming Esaki Diodes in Germanium bulk material was characterized. In doing so its processing characteristics were studied to determine whether it could be transferred into Aspect Ratio Trapping, ART, material. It was determined that transfer was feasible with the optimization of the spin on dopant process and strict control of the wet etching of the spin on dopant and Aluminum. Following process characterization electrical data was collected for a range of devices with varying process parameters. The maximum peak to valley current ratio was 1.5 and maximum peak current density was 5kA/cm². The PVCR value …

Biomedical Lance Ion Sensitive System, Charles D. Sturdevant

Journal of the Microelectronic Engineering Conference

The fabrication of a pH sensor which can be used in practical applications in biological and niedical fields was designed and manufactured using a new lance style ion sensitive field effect transistor. The lance can be used to measure pH levels in micro biological cultures without disruption of the culture and can be a powerful tool in real time Invitro medical diagnostics tool.

The reference electrode can be placed onto the chip by depositing a noble metal contact in the field region. This is referred as a Pseudo Reference Electrode, PRE. By bringing the PRE design closer to the membrane, …