Engineering Commons^™

Mask-Less Crystalline Silicon Solar Cell (May 2009), C K. Chan, R E. Pearson

Journal of the Microelectronic Engineering Conference

A mask-less crystalline silicon solar cell was made by using a surface texturing technique coupled with an oblique aluminum evaporation. To achieve this, trenches with a steep sidewall are mechanically grooved into the bulk silicon using the KS 775 Wafer Saw. More importantly, metal evaporation with the CVC evaporator at angles near parallel to the wafer surface allows deposition to occur along the side of the trenches creating the self-aligning front metal contacts. Of the four solar cells that made it through the processing, only one solar cell showed diode like 1-V characteristics. The dark conditions shows a diode 1-V …

A New 6" Metal Gate Pmos Process, Jessica Marks

Journal of the Microelectronic Engineering Conference

This paper presents the development, fabrication, and testing of a new 6” Metal Gate PMOS process. The new 6-inch Metal Gate PMOS process is an upgrade from the 4-inch Metal Gate PMOS process, which is the process currently used at RIT for the IC Technology course as ivell as the Short Course. The upgrades include the use of 6-inch wafers from 4-inch wafers, four levels per mask lithography instead of one level per mask lithography, ion implant instead of spin on dopant, and the number of control wafers was reduced from five wafers to three wafers. Development and fabrication of …

Photodiode Development For Fluorescence Spectroscopy Applications, Jeremy Goodman

Journal of the Microelectronic Engineering Conference

Two photodiode architectures were designed, built, and tested for comparison for implementation into a fluorescence spectroscopy, or fluorometric, system. All devices were fabricated on 4-inch, N-type silicon substrates. The photodiodes presented were tested for responsivity and response time, two main factors judging effective incorporation in fluorometric applications. The planar photodiode excels in responsivity due to the device’s large active-area; however, high junction capacitance greatly hinders the response time. The lateral photodiode had much lower junction capacitance than the planar, but exhibited lesser responsivity due to the decreased active area size. The lateral photodiode was chosen as a candidate for timeresolved …

Low Temperature Junction Formation In Silicon, Andrew Mccable

Journal of the Microelectronic Engineering Conference

The goal of this project was to examine the low temperature formation of silicon P-N junctions on SOl substrates. P+N and N+P diodes were fabricated with several different dopants at various implant doses. The effects of the silicon thickness were also examined. Existing theories of low temperature phosphorous solid-phase epitaxy (SPE) were verified through this study.

Process Design & Development Of Contact Cut Double Patterning, William A. Namestnik

Journal of the Microelectronic Engineering Conference

Optical double patterning allows for increased quality control over varying film stacks as well as allowing photolithography equipment to image smaller dense features. This is done by splitting dense patterns into two separate masks. A contact cut layer double patterning process was developed, and proved to be successful down to contact density of 4 μm CD by 4 μm density (4x4 μm CD x Density). Conventional dark field double patterning processes use two separate substrate etch steps (one etch step after each pass of lithography). This project developed a dark field double patterning process which incorporated light …

Nickel Nanodots For Memory Devices, Anthony J. Pacifico

Journal of the Microelectronic Engineering Conference

The formation of Nickel Nanodots (Ni-ND) were studied for the purpose of their potential use in memory devices. Ni-NDs were formed on SiO₂ and integrated into capacitors. These structures were then tested to demonstrate charge storage characteristics.

Characterization Of Microelectromechanical Systems (Mems) Flow Channel (May 2009), C Padilla

Journal of the Microelectronic Engineering Conference

MicroElectroMechanical System (MEMS) devices are integrations between mechanical engineering, electrical engineering, and microelectronic engineering. There are many different applications for MEMS such as micro mirrors, pumps, nozzle, and a plethora of sensor types. The Microelectronic engineering department at Rochester Institute of Technology offers a class in MEMS. Within this class, many MEMS applications are further studied and created, one being a gas flow sensor. In 2008, George Manos created a packaging fabrication process for the RIT flow sensor for further future analysis. Along with the use of the package, Dr. Lynn Fuller and Jessica Marks created the tested sensors. Through …

Surface Imaging Through Silylation, Chelsea R. Plourde

Journal of the Microelectronic Engineering Conference

Silylation is a surface imaging technique which allows silicon to absorb into photoresist in specified areas. Photoresist containing silicon creates a hard-mask which is resistant to oxygen plasma. This allows for the development process to occur strictly in dry etch systems. Surface imaging is a desirable technique because it removes the need to expose through the photoresist stack. Traditional lithography techniques require a high dose of ultra-violet (UV) light in order to penetrate to the bottom of a photoresist stack. It is critical, for quality imaging, that the photoresist not be over or under exposed. This creates a process window …

Front Contact Grid Design For Terrestrial Iii-V Concentrator Solar Cells, Stephen J. Polly, Michael Jackson, Seth Hubbard

Journal of the Microelectronic Engineering Conference

Photovoltaic devices can exhibit an increase in conversion efficiency as increasing power density is concentrated onto them. Design of the front contact grid is a major processing step that can govern the concentration at which the efficiency is at a peak. A series of equations provided by M. Green was used to design GaAs solar cells for concentrations of 1, 25, 50, 100, and 200 suns. The cells were processed and tested under a 1-sun calibrated AM1.5G spectrum, as well as a Large Area Pulsed Solar Simulator to measure device parameters under concentrated light. All devices—except the ones designed for …

Etching For Dual Damascene Fabrication, Samuel Rodens

Journal of the Microelectronic Engineering Conference

Dual damascene fabrication requires precise dry-etching. Two different methods were investigated: via-first and trench-first. It was found under conditions tested with that micromasking occurred, which was caused by damage to the resist. This caused the dielectric regions to be etched in the unmasked regions, as well as causing significant roughness. However, both etch techniques were found to have the capability of being used in a university dual damascene process.

4-Bit Microprocessor: Design, Simulation, Fabrication, And Testing, A J. Ryan, G O. Phillips, R E. Pearson, L F. Fuller

Journal of the Microelectronic Engineering Conference

The work presented demonstrates the unique ability of Rochester Institute of Technology’s Microelectronic Engineering department to design, simulate, fabricate, and test complex digital integrated circuits. Utilizing the resources available, the author would be the first undergraduate at RIT to successfully drive the creation of a microprocessor from design through fabrication to test. The microprocessor created is the most complex digital circuit ever fabricated at RIT. Fabrication was completed on three lots using the well-established RIT sub μm CMOS Process. Functional CMOS transistors were demonstrated at the Metal 1 level, but complex digital integrated circuits were not realized beyond that.

The Role Of Fluorine In Growth Rate Enhancement And Charge Supperssion On A Low Temperature Thermally Sio2 Interface Layer, Brian R. Silkey

Journal of the Microelectronic Engineering Conference

Integration of CMOS devices on to glass substrates has many process constraints. One of these is the melting point of the substrate, which is much lower than silicon. Normally a thermal oxide is desired for use as the gate dielectric, but at the lower temperature constraints due to the substrate it is not possible. One potential solution to this is they use of fluorine as an oxidation enhancement source is the ambient.

Metastable States And Leakage In Pn Junction Diodes, P Whiting, K Hirschman

Journal of the Microelectronic Engineering Conference

The low-temperature annealing kinetics of ion implanted silicon is a critical factor worthy of consideration when thin film crystalline silicon is processed on a low temperature substrate. Deep Level Transient Spectroscopy, Thermally Stimulated Current and Current-Voltage characteristics suggest that competition between Solid Phase Epitaxial Regrowth and dislocation loop formation is a critical factor in silicon implanted with P31 ions and annealed at temperatures ranging from 525°C to 65O°C. Solid Phase Epitaxy dominates the kinetics of fully amorphized samples annealed at 525°C, where shallow-level trap states dominate the reversed-bias leakage current of diodes. At low implanted doses (where the substrate is …

A Walking Silicon Robot, David W. Grund Jr, Lynn F. Fuller

Journal of the Microelectronic Engineering Conference

The goal of this project was to design and implement a MEMS process for the creation of a walking silicon robot using the equipment available at RIT. An attempt was carried out to create a mobility system based on the thermal expansion of polyimide joints as demonstrated by Ebefors. The designed process was successfully implemented through the oxidation of the joint surfaces. Issues with the Al resistor and polyimide lithography prevented the successful completion of the rest of the process.

Design & Fabrication Of An 8 Bit Adc, Garret Phillips

Journal of the Microelectronic Engineering Conference

MEMs devices at RIT utilize off chip circuitry to be properly utilized. This paper purposes an eight bit successive approximation analog to digital converter (ADC) to add to said devices as to simplify their operation. The ADC was designed and simulated using Mentor Graphics and Winspice software for the digital and analog components respectively. Lay out was then performed for the device as well as a simplified three bit version and various test circuits. Fabrication was done in the RIT SFML using RIT’s Sub-μ CMOS process, which uses a 2μm gate length. Functional transistors and simple devices …

Exploiting A Gsm Network For Precise Payload Delivery, Eugene A. Bourakov, Oleg A. Yakimenko, Nathan Slegers

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

This paper introduces the novel concept of using a GSM network for command of and communications with multiple aerial delivery systems. The research prototype of such a system, Snowflake-N, allows communicating with other network clients via a commercial Blackberry Curve 8310 handheld over a Bluetooth connection. A new architecture allows reassigning targets and sending other relevant commands (via web interface, by voice, data, or text messages) to an onboard autopilot, which is within a network reach, from any place in the world. Similarly, a current position of the descending system and target assignment can be viewed from any computer connected …

Performance Of A Fire-And-Forget Anti-Tank Missile With A Damaged Wing, John Harris, Nathan Slegers

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

A mathematical model is developed for an anti-tank missile and its guidance algorithms. The aerodynamic model is separated into two parts, the airframe and external lifting surfaces in order to model damage to the airframe. Radar data is compared to that of the proposed model and it is shown that the model accurately replicates the true flight dynamics. Two types of field handling damage are modeled, a damaged mid-body wing with 50% of its planform area missing, and an un-deployed mid-body wing. Monte Carlo simulations are performed for each type of damage and the eight possible mid-body wing locations. The …

Modeling The Risk Of A Failed Wind Turbine Blade Impacting A Power Transmission Line, Nathan Slegers, Jonathan Rogers, Mark Costello, Maria Puga, Patricia Arons

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Wind turbine installations are generally situated in proximity to power transmission lines that integrate generated power into the grid. Failure of a wind turbine that results in a blade or blade fragment thrown from the rotor can result in impact with a transmission line and lead to significant transmission line damage. The work reported here creates a mathematical model to assess the risk of this type of failure event occurring as a function of wind turbine characteristics and the relative position of the power transmission line. A comprehensive rotor blade flight dynamic simulation tool comprised of a rigid body representation …

Optimal Control For Terminal Guidance Of Autonomous Parafoils, Nathan Slegers, Oleg A. Yakimenko

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

This paper deals with the development of guidance, navigation and control algorithms for a prototype of a miniature aerial delivery system capable of high-precision maneuvering and high touchdown accuracy. High accuracy enables use in precision troop resupply, sensor placement, urban warfare reconnaissance, and other similar operations. Specifically, this paper addresses the terminal phase, where uncertainties in winds cause most of the problems. The paper develops a six degree-of-freedom model to adequately address dynamics and kinematics of the prototype delivery system and then reduces it to a two degrees-of-freedom model to develop a model predictive control algorithm for reference trajectory tracking …

Annealing Effects On The Optical Properties Of Semiconducting Boron Carbide, R. B. Billa, Tino Hofmann, Mathias Schubert, Brian W. Robertson

Nebraska Center for Materials and Nanoscience: Faculty Publications

Infrared vibrations of as-deposited and annealed semiconducting boron carbide thin films were investigated by midinfrared spectroscopic ellipsometry. The strong boron-hydrogen resonance at ~2560 cm⁻¹ in as-deposited films reveals considerable hydrogen incorporation during plasma-enhanced chemical vapor deposition. Extended annealing at 600 °C caused significant reduction in film thickness, substantial reduction of boron-hydrogen bond resonance absorption, and development of distinct blue-shifted boron-carbon and icosahedral vibration mode resonances. Our findings suggest that annealing results in substantial loss of hydrogen and in development of icosahedral structure, accompanied by strain relaxation and densification.

Design Of An 8-Channel Data Acquisition System For Measuring Diode Junction Temperature, Jason Maynard

Industrial and Manufacturing Engineering

The solid state lighting industry is striving to expand the use of light emitting diodes (LEDs) in more applications, particularly in high brightness applications. As the power of LEDs increase, heat removal becomes a critical issue. To improve device lifetime, quantum efficiency, and LED colour, the diode p-n junction temperature (Tj) must be kept to a minimum. Measuring this key parameter is difficult or impossible with direct methods, such as thermocouples and infrared cameras, due to the small size of LEDs. Fortunately, junction temperature can be measured indirectly by using a relationship between the diode forward voltage (Vf) and junction …

A Decision Support System For Capacity Management, Anton Slobodnik

Industrial and Manufacturing Engineering

Every manufacturer faces the challenge of managing production capacity. How effectively a company meets required capacity as compared to competitors will be a determinant of profitability and success.

This paper details the creation of a best of breed software that can act as a decision support system and help planners reschedule work, add shifts and make sure that the master production schedule is feasible before putting it into an MRP system.

As a part of my senior project I’ve created a Rough-Cut Capacity Tool that takes lead time into account and performs basic what if analysis on level loading a …

Ipas: International Paper Airplanes In Space, Getaway Special Team 2009

Reports and Proposals

No abstract provided.

Visualization Methods And User Interface Design Guidelines For Rapid Decision Making In Complex Multi-Task Time-Critical Environments, Sriram Mahadevan

Browse all Theses and Dissertations

Real-world scenarios are complex dynamic systems that are often overloaded with information. Effective performance of these dynamic systems depends on the objects in such systems and the relationship among them. The control of many of these systems is semi-automated. Human operators constantly monitor and control these systems, assess the situation and often make decisions under time pressure. However, this supervisory control paradigm in a dual-task environment can be a very challenging task. Existing interface design methodologies and techniques have not delved deeply enough into defining information displays for complex, dynamic, time-critical, dual-task environments with capabilities for rapid task change awareness …

A Macrobending Singlemode Fiber Based Refractometer, Pengfei Wang, Yuliya Semenova, Qiang Wu, Gerald Farrell, Yungqiang Ti, Jie Zheng

Articles

A novel macrobending based all-fiber refractometer sensor with a simple optical configuration is proposed and investigated both theoretically and experimentally. The proposed fiber refractometer sensor consists of a single loop structure of bare macrobending standard singlemode fiber (SMF28) with a selected bending radius and reduced cladding diameter. The well-known scalar approximation theory is employed to theoretically predict the characteristics of the proposed fiber refractometer sensor. An approach to improve the resolution of the refractometer is presented, which shows that the refractometer with a reduced cladding diameter of 81 μm has an experimentally verified resolution of 5.75105 for a refractive index …

Analysis And Performance Evaluation Of An All-Fiber Wide Range Interrogation System For A Bragg Grating Sensor Array, Ginu Rajan, Yuliya Semenova, Gerald Farrell

Articles

Analysis and performance evaluation of a macro-bend ¯ber based interrogation system for a Bragg grating sensor array is presented. Due to the characteristic properties of the macro-bend ¯ber ¯lter such as polarization and temperature dependence and the total noise associated with the ratiometric system, a best ¯t ratio slope is required to interrogate multiple FBGs whose peak wavelengths are spread over a wide wavelength range, rather than the optimal slope for individual FBG. In this paper for investigation we have used an FBG array with 5 FBGs with peak re°ected wavelengths lying between 1525 nm and 1575 nm. The analysis …

Dynamic Evaluation Of New York State’S Aluminum Pedestrian Signal Pole System, Scott K. Rosenbaugh, Ronald K. Faller, Karla A. Lechtenberg, Robert W. Bielenberg, Dean L. Sicking, John D. Reid

Mid-America Transportation Center: Final Reports and Technical Briefs

The New York State Department of Transportation (NYSDOT) mounts pedestrian “hand/man” signals to aluminum

poles and uses frangible transformer bases to allow the system to break away. However, engineers at NYSDOT believed that the material properties of the aluminum poles themselves would allow the pedestrian signal poles to break away without the use of transformer bases. Elimination of the frangible transformer base would result in significant savings.

An aluminum pedestrian signal pole system was erected at the Valmont testing facility and tested with the Valmont- MwRSF/UNL pendulum with crushable nose in accordance with NCHRP Report No. 350 test designation no. …

Preserving Assets In At-Risk Municipalities: Financial Strategies For Climate Change Adaptation, New England Environmental Finance Center

Climate Change

A large share of America's population, businesses and economic activity now occurs in coastal areas. At the same time, during this century many coastal communities are likely to be severely impacted by sea level rise and increased storm surge and tidal flooding.

“What to do” about this vulnerability is the subject of this brief. It is intended to help municipalities identify courses of action and steps they might take toward increasing their resilience, especially regarding financial resources that will need to be allocated toward the various strategies identified.

Recovery Of Biodiesel Precursors From Heterotrophic Microalga Chlorella Protothecoides, Peter B. Merkle

United States Department of Energy: Publications

This working paper describes an experimental program to assess the suitability of largescale separation processing of algal biomass in aqueous culture. It assumes the possibility of successful large-scale growth of heterotrophic Chlorella protothecoides to produce algal lipid/free fatty acid (FFA) biodiesel precursors.

Integrated Bipolar Plate - Gas Diffusion Layer Design For Polymer Electrolyte Membrane Fuel Cells, David N. Neff

Browse all Theses and Dissertations

Bipolar plates compose a large portion of the weight and manufacturing costs in fuel cells. Bipolar plates are metal plates that separate each membrane-electrode assembly in a fuel cell stack. They provide structural strength, contain flow channels for fuel transport, and conduct electricity in the fuel cell. Electricity also flows through the gas diffusion layer (GDL) which lies next to the bipolar plate. Because the GDL is separate from the bipolar plate, there is a contact resistance as the electricity flows from one to the other. The scope of this thesis is to research an efficient way of manufacturing a …