Engineering Commons^™

Topology And Logic Programming Semantics, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Logic programming employs logic as a programming language. Thus a logic program consists of a set of clauses of a certain form most often a subset of the clauses of first order logic viewed as axioms. Computation in this paradigm is deduction from these axioms via some interpreter.

Logic programming semantics is concerned with background theory for logic programming. It tries to provide models for logic programs to give them their intended meaning and to connect them with practically implementable interpreters.

Pinched Diodes, Quynh Nguyen

Journal of the Microelectronic Engineering Conference

While applications for diodes operating under forward bias have been researched extensively, the useful application in reverse bias mode is relatively unexplored. Resistance modulation in avalanche mode offers new possibility for utilization. The purpose of this experiment is to characterize a diode utilizing a differential negative resistance (DNR) scheme showing a decrease in current with an increase in voltage.

The Iris Project: Ccd's, Image Recognition, And All That Jazz, Abram M. Detofsky

Journal of the Microelectronic Engineering Conference

The Identity Recognition and Imaging System (IRIS) Project was initiated to explore the fabrication and integration of a CCD imaging array into a complete image recognition system. Such a system has now been realized in part, and consists of an surfacechannel 64-by-64 pixel CCD array, external driver circuitry, data acquisition board, and a Win95-based PC running a custom pattern recognition software package called TALONir.

Bf2 Implanted Stacked A-Silicon Gate Capacitors, David Sanchez

Journal of the Microelectronic Engineering Conference

BF₂ implanted stacked z-silicon (SAS) electrode capacitors were fabricated on n-type silicon substrates. The purpose of this electrode scheme was to quantify the effectiveness of stacked films in suppressing boron penetration into the dielectric and substrate. A 150A thick silicon dioxide was used as the capacitor dielectric. The top α-silicon electrode was deposited in a three step process using low pressure chemical vapor deposition (LPCVD). A controlled sample was fabricated using LPCVD polysilicon (Poly) as the top electrode. The samples were tested for dielectric degradation using voltage ramping techniques. The breakdown field was recorded for 2 different size capacitor …

Fabrication Of Twin-Well Cmos, Linh V. Phan

Journal of the Microelectronic Engineering Conference

A single-mask self aligned Twin-well process has been integrated into RIT’s CMOS technology. These wells are self aligned to increase package density. The process has been simulated using TMA Suprem IV simulation tool. The simulated parameters were used in the actual fabrication. The wells are used to optimize both n- and p-channel active devices. The subthreshold leakage currents in isolated pmos and nmos devices are -1.28 pA.4/μn and 3.56 nA/μm of channel width, respectively when the devices were biased at < 5 volts. In addition, the twinwell process has produced active n- and p-channel FET’s with excellent characteristics such as low threshold voltage, low subthreshold swing, and high transconductance.

Design Of Experiments Using Tma Workbench, James Daniels

Journal of the Microelectronic Engineering Conference

TMA WorkBench software is used to interface with Suprem4 process simulator and Medici electrical test software in order to set up, run and analyze Design of Experiments for process simulation. A method for simulation tuning was found, and an example experiment was run and analyzed. Comparison to a fabricated experiment was planned in order to provide feedback for simulation tuning and to verify a simulated approach to process experimenting. Least squares analysis was used to find response function coefficients, as well as to plot factor-response contour maps.

Integrated Electronics For Micro-Electromechanical Devices, Michael J. Frachel

Journal of the Microelectronic Engineering Conference

With the increased usage of microelectromechanical devices (MEMs) today, the use and design of systems to control and monitor such devices has become increasingly important. In interests of simplifying packaging and increasing yield, the possibility of putting such control and monitoring systems on chip with the micro-electromechanical machines is suggested as an elegant solution. Simplified scaling of the micro-electromechanical machine/circuit system as one can also be a benefit of this integrated process. This project integrates a basic n+ poly gate PMOS process with the additional steps necessary to create simple suspended polysilicon beam micromachines. These beams can be used as …

The Fabrication Of Corrugated Silicon Surfaces, Alicia N. Bineyard

Journal of the Microelectronic Engineering Conference

Corrugation of silicon surfaces is desired for a variety of applications requiring availability of increased surface area and modification of optical properties of thin films. Such surfaces also prevent refractive trapping in luminescent films and can provide lambertian emissive surfaces. The objective of this research is to fabricate these corrugated silicon surfaces using a specially customized mask consisting of four different design patterns. The goal is to prove that the smallest design pattern will provide the best characteristics for enhancing the light emission of luminescent films. The surface morphology, etching process and the luminescent properties of the etched samples have …

Thin Gate Oxides Over Nitrogen Implanted Silicon, Luis J. Lopez

Journal of the Microelectronic Engineering Conference

Here we study the effects of implanting nitrogen (N’) into the substr e prior to thermal oxidation. We found that for implant doses higher than 1x10¹⁴ /cm² the oxidation rate is reduced between 10% and 75%. Also, the oxide thickness uniformity across the substrates was found to be degraded after the implantation, even though better uniformity was expected. Oxide characterization will be performed to compare the implanted areas to bare Si regions. The reported benefits of incorporating nitrogen into Si make this an interesting study for future generations of gate oxides.

Test Patterns For Chemical Mechanical Polish Characterization, Stanley J. Dobek

Journal of the Microelectronic Engineering Conference

I studied the effect of wafer topography on the chemical mechanical polishing (CMP) process. This was done by first designing test structures. A mask set of these structures was then designed and fabricated. Wafers were patterned with the test mask and then were polished. The result was that a pattern dependency was seen on the wafers. The polishing process was effected by the surface topography.

Development Of Process Monitoring Monitoring Strategies For Contamination Control Utilizing A Surface Charge Analyzer, Raj Chakraborty

Journal of the Microelectronic Engineering Conference

The study done was to develop strategies that utilize the measurement and analytical capabilities of a Semitest Surface Charge Analyzer (SCA 2000) and monitor contamination caused during certain processes and in furnaces in an IC fab. A significant drop in average minority carrier lifetime and an increase in fixed oxide charge was observed. Counterdoping was also observed in one of the furnaces.

Soi Via Wafer Bonding, Bart U. Meshelle

Journal of the Microelectronic Engineering Conference

An attempt is made at the preparation of silicon-on-insulator (SOl) substrates suitable for device fabrication. This is done by the high temperature bonding of a pair of silicon wafers upon which oxide layers have been thermally grown. One of the pair is then ground back to a suitable thickness. Bonding strength and defects are also evaluated.

Investigation Of Buried Channel Pmos, Chuan-Hsing Chen

Journal of the Microelectronic Engineering Conference

The objective of this project is to investigate the electrical characteristics of Buried Channel PMOS for twin-well CMOS process. Project involves the investigation of the P-MOSFET by varying the standard boron (B11) threshold adjust implant dose. In addition, the effect of adding a phosphorus (P31) counter doping implant on the device characteristics is also investigated. The addition of counter doping implant will reduce the thickness of the buried channel created by the threshold adjust implant. Test results for the counter doped twin-well process shows stronger transistor turn-off and lower off-state leakage current without significantly affecting the on-state current drive.

Dc Reactive Sputtering Of Transparent Conducting Indium Tin Oxide, Dan Fullerton

Journal of the Microelectronic Engineering Conference

A DC reactive sputtering process for thin transparent conducting films of indium tin oxide was developed at RIT for a variety of uses. Thin films were sputtered in a CVC-601 batch sputterer from a 200mm indium-tin target in an argon/oxygen ambient onto 3-inch silicon wafers and 2x3-inch glass slides. An experiment utilizing a central composite design with variables of oxygen flow, argon flow, and DC power was performed. As-sputtered films exhibited characteristics of either high resistivity and high transmittance due to an abundance of oxygen in the film, or low resistivity and low transmittance due to an oxygen deficiency in …

The Design Of An Inorganic Barc, Andrew Veter

Journal of the Microelectronic Engineering Conference

A methodology was arrived at for the design of an inorganic bottom antireflective coating (BARC). The design methodology consisted of four parts. First, a material compatible with IC processing was chosen. Second, simulation was performed to determine the optimum optical properties of the material, where the materials extinction coefficient, and film thickness were varied to produce zero substrate reflectivity. Third, the stochiometry of the material was varied through experimentation to produce a film with the index of refraction and extinction coefficient as close as possible to the simulation results. Fourth, the results of step three were used in simulation to …

Implementation And Electrical Characterization Of Shallow Trench Isolation, John A. Castellana

Journal of the Microelectronic Engineering Conference

Shallow trench isolation (STI) planarized with chemical mechanical polishing (CMP) has replaced LOCOS as the conventional isolation technique for sub-micron devices 171. The implementation and feasibility of STI has been examined for future device fabrication at RIT. STI test structures have been fabricated to investigate leakage currents between adjacent NMOS transistors in a p-substrate. Trenches were dry etched to a target depth of 2 μm to isolate n+ regions with a junction depth of 0.89 μm. Trench Refill was done with LTO planarized by chemical mechanical polishing (CMP). By testing source/drain n+ regions isolated by two trenches, leakage …

Super Resolution Techniques For Duv Optical Lithography, Dayo Pinkney

Journal of the Microelectronic Engineering Conference

As device geometries shrink, new illumination sources will be needed to obtain practical resolution. The krypton fluoride (KrF) excimer laser (248nm) is capable of 0.30 μm resolution with conventional illumination methods. A weak quadrupole off-axis illumination technique combines the advantages of two-beam imaging (off-axis illumination), and three-beam imaging (conventional illumination). This allows for the advantage of increased Depth-of-Focus (DOF) without the degradation of isolated patterns. This method is suitable for use with an attenuated phase shift mask (APSM) which also enhances resolution and DOF.

Design And Characterization Of An Optical Proximity Correction (Opc) Mask, Sumir Varma

Journal of the Microelectronic Engineering Conference

A normal binary chrome mask is designed with optical proximity correction features to test their effect on the lithographic image formed. A significant image improvement is seen due to the addition of the OPC features.

Resist Performance Using Spectroscopic Ellipsometry, Michael Y. Chan

Journal of the Microelectronic Engineering Conference

The technique of spectroscopic ellipsometry was employed to study the effects of residual solvents in chemically amplified photoresists on the dissolution characteristics and optical constants of the spin-cast film. Ellipsometric measurements were made for resist films with no bake, with soft bakes, and with both soft bakes and post-exposure bakes, at various baking temperatures. Exposures of these films were performed using a KrF excimer laser (248 nm) with a beam splitter lens element to increase the exposure area. To increase the accuracy of the experimental data, measurements were made at three different angles over a sampling wavelength range of 200 …

Twin-Well Cmos Integration, Kenneth A. Gendron

Journal of the Microelectronic Engineering Conference

A self-aligned twin-well process has been developed for RIT’s Student CMOS Factory. These wells are self-aligned providing increased packing density; which, will allow for increased speed and reduction in defectively levels. In addition the twin-well process offers: decreased Early effect, increased punchthrough voltage and, reduced latch-up susceptibility, for those devices normally manufactured in substrate. Standard RIT Student Factory CMOS implements a p-well process. Four micron by 32 micron p-channel devices were tested to determine process performance. Early voltage was increased from 9.4V for p-well, to 38.8V for twin-well CMOS. Punchthrough voltage was increased in magnitude from 8V for p-well to …

Winter/Spring 1997, 90.9 Wmpg Fm

WMPG Program Guides

Newspaper format

Summer 1997, 90.9 Wmpg Fm

WMPG Program Guides

"WMOG Bares it All! Live Broadcasts in Public"

Cosmic Calling

Syracuse University Magazine

No abstract provided.

Design Of A Low-Cost, One-Way, Wireless Digital Communication System, Kristopher L. Young

Honors Capstone Projects and Theses

No abstract provided.

Design Of Automotive Structural Components Using High Strength Sheet Steels Mechanical Properties Of Materials (Aging Effect), Shaojie Wu, Chi-Ling Pan, Wei-Wen Yu

CCFSS Library (1939 - present)

INTRODUCTION It has been known for years that mechanical properties of thin sheet steels, such as yield strength, tensile strength, and ductility, are affected by aging (Chajes et al. 1963, Hertzberg 1989, Yu 1991). The aging effect on mechanical properties can be described as follows. For a virgin steel that is initially loaded in tension beyond its yield strength and into strain hardening state and then unloaded to zero stress, the yield and tensile strengths of the steel increase while the ductility of the steel decreases if the steel is reloaded in tension again after a period of time from …

Biological Response To Particulate Debris: In Vitro And In Vivo Studies, A. S. Shanbhag, J. E. Dowd, J. J. Jacobs, D. M. Tramaglini, T. T. Glant, J. Black, H. E. Rubash

Cells and Materials

In this study, we compared the results of a human monocyte in vitro model and a canine in vivo model, to evaluate the response to different types of particulate wear debris. Both the in vitro and in vivo studies demonstrated that titanium-6 aluminum-4 vanadium (TiAIV), ultrahigh molecular weight polyethylene (UHMWPE) and other particulate wear debris are stimulatory to macrophages and elicit release of several identifiable mediators involved in periprosthetic inflammation and bone resorption. Further, in the in vivo studies, these same particles initiated the formation of interfacial membranes which were histologically and biochemically similar to those seen in clinically failed …

Sintered Carbonate Apatites As Bone Substitutes, Yutaka Doi

Cells and Materials

Sintering of carbonate apatites was investigated and the usefulness of sintered specimens as bone substitutes was evaluated in vitro and in vivo. Osteoclasts appeared to be capable of resorbing sintered carbonate apatite, which was as soluble as deproteinated bone and much more soluble than sintered hydroxyapatite in weak acids. In skull defects of Wistar rats, sintered carbonate apatite particles resorbed to an appreciable extent, but the rate of resorption did not exceed that of new bone formation. At 4 weeks after implantation the defects were filled almost completely with new bone that compared favorably with the host bone. These …

Detachment Of Human Endothelial Cells Under Flow From Wettability Gradient Surfaces With Different Functional Groups, T. G. Ruardy, H. E. Moorlag, J. M. Schakenraad, H. C. Van Der Mei, H. J. Busscher

Cells and Materials

In this study, the position bound adhesion, spreading and detachment under flow of human umbilical cord endothelial cells (HUVEC) was studied on a dichlorodimethylsilane (DDS), dimethylocta-decylchlorosilane (DOCS) and tridecafluor-1,1,2,2-tetrahydrooctyl-1-dimethylchlorosilane (TFCS) wettability gradient on glass. Gradient surfaces were prepared by the diffusion method and characterized by the Wilhelmy plate technique for their wettability and by X-ray photoelectron spectroscopy (XPS) for their chemical composition. Quantitative analysis of the cellular response on the wettability gradient surfaces showed that the position bound cellular response was influenced by wettability for each type of gradient in a different way. On DDS-wettability gradients, cells withstood flow best …

Heat-Treatment Behavior Of High-Palladium Dental Alloys, Qiang Wu, William A. Brantley, John C. Mitchell, Stanley G. Vermilyea, Jianzhong Xiao, Wenhua Guo

Cells and Materials

Four high-palladium dental alloys were cast, quenched following solidification, and heat treated at temperatures ranging from 200° to 1,800°F. The Vickers hardness of each alloy was measured, and microstructural changes were studied by scanning electron microscopy (SEM). Phase transformations were investigated by thermomechanical analysis (TMA). Heat treatment at 1,600° and 1,800°F significantly decreased the hardness of one Pd-Cu-Ga alloy, compared to the as-cast condition, as did heat treatment at 1,800°F for the other Pd-Cu-Ga alloy and one Pd-Ga alloy, and yielded fine-grained microstructures of the palladium solid solution. There were generally no significant changes in the hardness of the other …

Synthesis Of A Low-Carbonate High-Charge Hydrotalcite-Like Compound At Ambient Pressure And Atmosphere, Ravi K. Kukkadapu, Marc S. Witkowski, James E. Amonette

United States Department of Energy: Publications

Hydrotalcite (HT), a clay mineral, is constructed of brucite-like layers [Mg(OH)₂] in which substitution of Al³⁺ for Mg²⁺ at a mole ratio of 1:3 yields a net positive charge. This layer charge is compensated by exchangeable CO₃ 2- anions located (along with adsorbed water molecules) in the interlayer region. Numerous analogues of HT [i.e., “hydrotalcite-like” compounds (HTLCs)] have been synthesized with a variety of M²⁺/M³⁺ combinations,M²⁺/M³⁺ ratios, and interlayer anions.1-10 The compositions of these HTLCs are usually expressed using a generalized form of the formula for a substituted brucite, …