Matching Items (6)
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- All Subjects: solar
- Creators: Kozicki, Michael
- Creators: Bertoni, Mariana
- Member of: Theses and Dissertations
- Resource Type: Text
- Status: Published
Description
In competitive Taekwondo, Electronic Body Protectors (EBPs) are used to register hits made by players during sparring. EBPs are comprised of three main components: chest guard, foot sock, and headgear. This equipment interacts with each other through the use of magnets, electric sensors, transmitters, and a receiver. The receiver is connected to a computer programmed with software to process signals from the transmitter and determine whether or not a competitor scored a point. The current design of EBPs, however, have numerous shortcomings, including sensing false positives, failing to register hits, costing too much, and relying on human judgment. This thesis will thoroughly delineate the operation of the current EBPs used and discuss research performed in order to eliminate these weaknesses.
ContributorsSpell, Valerie Anne (Author) / Kozicki, Michael (Thesis director) / Kitchen, Jennifer (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Layers of intrinsic hydrogenated amorphous silicon and amorphous silicon carbide
were prepared on a polished, intrinsic crystalline silicon substrate via plasma-enhanced chemical vapor deposition to simulate heterojunction device relevant stacks of various materials. The minority carrier lifetime, optical band gap and FTIR spectra were observed at incremental stages of thermal annealing. By observing the changes in the lifetimes the sample structure responsible for the most thermally robust surface passivation could be determined. These results were correlated to the optical band gap and the position and relative area of peaks in the FTIR spectra related to to silicon-hydrogen bonds in the layers. It was found that due to an increased presence of hydrogen bonded to silicon at voids within the passivating layer, hydrogenated amorphous silicon carbide at the interface of the substrate coupled with a hydrogenated amorphous silicon top layer provides better passivation after high temperature annealing than other device structures.
were prepared on a polished, intrinsic crystalline silicon substrate via plasma-enhanced chemical vapor deposition to simulate heterojunction device relevant stacks of various materials. The minority carrier lifetime, optical band gap and FTIR spectra were observed at incremental stages of thermal annealing. By observing the changes in the lifetimes the sample structure responsible for the most thermally robust surface passivation could be determined. These results were correlated to the optical band gap and the position and relative area of peaks in the FTIR spectra related to to silicon-hydrogen bonds in the layers. It was found that due to an increased presence of hydrogen bonded to silicon at voids within the passivating layer, hydrogenated amorphous silicon carbide at the interface of the substrate coupled with a hydrogenated amorphous silicon top layer provides better passivation after high temperature annealing than other device structures.
ContributorsJackson, Alec James (Author) / Holman, Zachary (Thesis advisor) / Bertoni, Mariana (Committee member) / Kozicki, Michael (Committee member) / Arizona State University (Publisher)
Created2016
Description
The project described here is a solar powered intrusion detection system consisting of three modules: a battery recharging circuit, a laser emitter and photodetector pair, and a Wi- Fi connectivity board. Over the preceding seven months, great care has been taken for the design and construction of this system. The first three months were spent researching and selecting suitable IC's and external components (e.g. solar panel, batteries, etc.). Then, the next couple of months were spent ordering specific materials and equipment for the construction of our prototype. Finally, the last two months were used to build a working prototype, with a substantial amount of time used for perfecting our system's packaging and operation. This report will consist of a detailed discussion of our team's research, design activities, prototype implementation, final budget, and final schedule. Technical discussion of the concepts behind our design will assist with understanding the design activities and prototype implementation sections that will follow. Due to the generous funding of the group from the Barrett Honors College, our overall budget available for the project was $1600. Of that amount, only $334.51 was spent on the actual system components, with $829.42 being spent on the equipment and materials needed for the testing and construction of the prototype. As far as the schedule goes, we are essentially done with the project. The only tasks left to finish are a successful defense of the project at the oral presentation on Friday, 29 March 2013, followed by a successful demo on 26 April 2013.
ContributorsTroyer, Nicole L. (Co-author) / Shtayer, Idan (Co-author) / Guise, Chris (Co-author) / Kozicki, Michael (Thesis director) / Roedel, Ronald (Committee member) / Goodnick, Stephen (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2013-05
Description
The metallization and interconnection of Si photovoltaic (PV) devices are among some of the most critically important aspects to ensure the PV cells and modules are cost-effective, highly-efficient, and robust through environmental stresses. The aim of this work is to contribute to the development of these innovations to move them closer to commercialization.Shingled PV modules and laser-welded foil-interconnected modules present an alternative to traditional soldered ribbons that can improve module power densities in a cost-effective manner. These two interconnection methods present new technical challenges for the PV industry. This work presents x-ray imaging methods to aid in the process-optimization of the application and curing of the adhesive material used in shingled modules. Further, detailed characterization of laser welds, their adhesion, and their effect on module performances is conducted. A strong correlation is found between the laser-weld adhesion and the modules’ durability through thermocycling. A minimum laser weld adhesion of 0.8 mJ is recommended to ensure a robust interconnection is formed.
Detailed characterization and modelling are demonstrated on a 21% efficient double-sided tunnel-oxide passivating contact (DS-TOPCon) cell. This technology uses a novel approach that uses the front-metal grid to etch-away the parasitically-absorbing poly-Si material everywhere except for underneath the grid fingers. The modelling yielded a match to the experimental device within 0.06% absolute of its efficiency. This DS-TOPCon device could be improved to a 23.45%-efficient device by improving the optical performance, n-type contact resistivity, and grid finger aspect ratio.
Finally, a modelling approach is explored for simulating Si thermophotovoltaic (TPV) devices. Experimentally fabricated diffused-junction devices are used to validate the optical and electrical aspects of the model. A peak TPV efficiency of 6.8% is predicted for the fabricated devices, but a pathway to 32.5% is explained by reducing the parasitic absorption of the contacts and reducing the wafer thickness. Additionally, the DS-TOPCon technology shows the potential for a 33.7% efficient TPV device.
ContributorsHartweg, Barry (Author) / Holman, Zachary (Thesis advisor) / Chan, Candace (Committee member) / Bertoni, Mariana (Committee member) / Yu, Zhengshan (Committee member) / Arizona State University (Publisher)
Created2023
Description
The investigation into wide band gap semiconductors for use in tandem solar cells has become an increasingly more researched area with many new absorbers outlining the landscape. Pairing silicon with another cheap wide band gap semiconductor absorber can generate more efficient solar cell, which could continue to drive up the energy output from solar. One such recently researched wide band gap absorber is ZnSnN2. ZnSnN2 proves too difficult to form under most conditions, but has the necessary band gap to make it a potential earth abundant solar absorber. The deposition process for ZnSnN2 is usually conducted with Zn and Sn metal targets while flowing N2 gas. Due to restrictions with chamber depositions, instead ZnO and SnO2 targets were sputtered with N2 gas to attempt to form separate zinc and tin oxynitrides as an initial single target study prior to future combinatorial studies. The electrical and optical properties and crystal structure of these thin films were analyzed to determine the nitrogen incorporation in the thin films through X-ray diffraction, UV-Vis spectrophotometry, and 4-point probe measurements. The SnO2 thin films showed a clear response in the absorption coefficient leading but showed no observable XRD peak shift. Thus, it is unlikely that substantial amounts of nitrogen were incorporated into SnO¬2. ZnO showed a clear response increase in conductivity with N2 with an additional shift in the XRD peak at 300 °C and potential secondary phase peak. Nitrogen incorporation was achieved with fair amounts of certainty for the ZnO thin films.
ContributorsTheut, Nicholas C (Author) / Bertoni, Mariana (Thesis director) / Holman, Zachary (Committee member) / Materials Science and Engineering Program (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Energy poverty is the lack of access to the basic energy resources needed for human development. Fossil fuels, through their heavy emissions and transience, are slowly but surely leaving room for change in the energy sector as renewable energy sources rise to the challenge of sustainable, clean, and cost-efficient energy production. Because it is mostly located in rural areas, solutions crafted against energy poverty need to be appropriate for those areas and their development objectives. As top contenders, photovoltaics insertion in the energy market has largely soared creating, therefore, a need for its distributed energy resources to interconnect appropriately to the area electrical power system. EEE Senior Design Team 11 saw in this the need to design an advanced photovoltaic inverter with those desired grid functions but also leveraging the technological superiority of wide bandgap devices over silicon semiconductors. The honors creative project is an integral part of the senior design capstone project for Team 11. It has a two-front approach, first exploring the IEEE 1547-2018 standard on distributed energy resources; then focusing on the author’s personal contribution to the aforementioned senior design project: digital signal processing and grid support implementation. This report serves as an accompanying write up to the creative project.
ContributorsTall, Ndeye Maty (Author) / Ayyanar, Raja (Thesis director) / Kozicki, Michael (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05