Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Materials Engineering (2)
- Materials engineering (2)
- Silicon (2)
- Solar (2)
- Bond strength (1)
-
- Borosilicate (1)
- Cast (1)
- Digital Mirror Device (1)
- Electrokinetics (1)
- Electroosmosis (1)
- Electrostatic actuation (1)
- Fabricate (1)
- Glass (1)
- Iridescence (1)
- LED (1)
- Lantern (1)
- Lighthouse (1)
- Lunalight (1)
- MEMS (1)
- Microfabrication (1)
- Micromirror (1)
- Nanoparticles (1)
- Onemillionlights (1)
- Opal (1)
- PDMS (1)
- Photonic crystal (1)
- Polymethyl methacrylate (1)
- Prism (1)
- Pyrex (1)
- Quantum Dots (1)
Articles 1 - 9 of 9
Full-Text Articles in Engineering
Bond Strength Characterization Of Su-8 To Su-8 For Fabricating Microchannels Of An Electrokinetic Microfluidic Pump, Nash Anderson
Bond Strength Characterization Of Su-8 To Su-8 For Fabricating Microchannels Of An Electrokinetic Microfluidic Pump, Nash Anderson
Materials Engineering
Photosensitive negative resist polymer layers of SU-8 2050 were adhered to 100 mm n-type silicon and Pyrex wafers via spin coating. These wafers were then bonded together at various temperatures of 100 ͦC, 120 ͦC, 140 ͦC, 150 ͦC, 160 ͦC, and 180 ͦC. The target thickness of each SU-8 layer was 100 µm. Photolithography was used to create microfluidic channels within the SU-8. An n-type silicon wafer and a Pyrex wafer, each with an SU-8 layer, were brought together on the “hard bake” or final step of SU-8 polymerization. A pressure of ~300 KPa was applied during the hard …
Creating A Solar Cell Array From A Single Silicon Wafer, Samyukta Gade, Roderick Marstell
Creating A Solar Cell Array From A Single Silicon Wafer, Samyukta Gade, Roderick Marstell
Materials Engineering
Two different processes to create multi-celled solar panels from single wafers were made and implemented. To do this, the cells must not have a common ground, and both designs use different approaches to solve this problem. One utilizes a 2.9 µm deep n-type well within a 10.74 µm deep p-type well in an n-type wafer. There are two cells in series, which has a theoretical voltage of 1 V. The cells are connected in series with 1.9 µm thick gold traces. Any area that the gold is not in contact with the silicon has a .5 µm layer silicon dioxide …
Improving Solar Cell Performance Using Cdse/Zns Core/Shell Quantum Dots In A Spectral Conversion System, Buddy Bump
Improving Solar Cell Performance Using Cdse/Zns Core/Shell Quantum Dots In A Spectral Conversion System, Buddy Bump
Materials Engineering
Solar cells have been found to absorb light more efficiently and effectively when the energy of incoming photons matches the electronic band gap of the solar cell. Spectral conversion of light from UV to lower energy wavelengths can improve solar cell efficiency an estimated 14.5%. Cadmium Selenium/Zinc Sulfide Core/Shell quantum dots have been successfully embedded in PDMS silicone elastomer. Using a Keithley 2400 Electrometer with Labview software, voltage and current characteristics have been recorded in steps of 10 mV with a wait time of 250 ms on a commercially available solar cell using an artificial solar spectrum created by a …
Design And Fabrication Of Serpentine-Hinged Silicon Micro-Mirror Devices, Nicholas Wiswell
Design And Fabrication Of Serpentine-Hinged Silicon Micro-Mirror Devices, Nicholas Wiswell
Materials Engineering
Seven different actuating micro-mirror designs were created and verified via finite element analysis. Two were straight torsion beam hinge designs representative of previous work at Cal Poly; the remaining five were new designs incorporating serpentine hinges. The surface area of these mirror devices ranged from 0.5 square millimeters to 12.5 square millimeters. Geometric patterns representing the device profiles were created and used to obtain photolithographic masks. Beginning with a 400μm thick, 100mm diameter silicon on insulator wafer, a silicon dioxide layer was thermally grown on the surface at 1050 degrees Celsius. Positive photoresist was then spun onto the wafer at …
Fabricating Replacement Glass Prisms For The Piedras Blancas Lighthouse, Daniel Garcken
Fabricating Replacement Glass Prisms For The Piedras Blancas Lighthouse, Daniel Garcken
Materials Engineering
The objective of this project was to design and create a process for manufacturing replacement glass prisms for the Piedras Blancas lighthouse and several other lighthouses nationwide. The prisms were designed to be in multiple metal arrays spread across the floor of the beacon room (the topmost room of the lighthouses). The prisms functioned to transmit extra, radiant light from the beacon light through the floor of the beacon room and disperse it into the maintenance room below. Using computer aided drafting (CAD) software, an original prism was measured and modeled; the corresponding mold was also modeled. G-codes for controlling …
Synthesis Of White Cadmium-Selenium Quantum Dots, Kyle Reilly
Synthesis Of White Cadmium-Selenium Quantum Dots, Kyle Reilly
Materials Engineering
A process was developed for the synthesis of cadmium-selenium quantum dots that fluoresce at multiple wavelengths, giving a white color to the solution. The process involved making a selenium pre-cursor, then a cadmium precursor, then injecting the selenium precursor into the cadmium precursor and extracting a sample. Once the a repeatable process for synthesizing white quantum dots was developed, the absorption and fluorescence was measured and recorded over a period of two weeks. In the development of the process, the key variables were the temperature of the cadmium precursor and the time between injecting the selenium precursor and extracting the …
The Effects Of Concentration, Stir Rate, And Processing Temperature On The Iridescence Of Polymethyl Methacrylate Nanoparticles, David Baruela
The Effects Of Concentration, Stir Rate, And Processing Temperature On The Iridescence Of Polymethyl Methacrylate Nanoparticles, David Baruela
Materials Engineering
Synthetic opals were synthesized by creating polymethyl methacrylate (PMMA) nanospheres in order to determine which conditions would create the best iridescent samples. The factors affecting the iridescence were nanosphere concentration, stir rate, and processing temperature. PMMA solutions were made by adding 17 mg of granular azobis to a solution of 16 mL of distilled water with 3 mL of methyl methacrylate (MMA). The solution was stirred at different rates, slow and fast, and different temperatures, 70 °C and 90 °C, under a constant flow of nitrogen gas for 40 minutes until the polymerization reaction was complete. Glass substrates were prepared …
The Design And Fabrication Of A Silicon Membrane For Electrostatic Actuation, Elizabeth L. Brooks
The Design And Fabrication Of A Silicon Membrane For Electrostatic Actuation, Elizabeth L. Brooks
Materials Engineering
An electrostatically actuated silicon membrane was designed and fabricated utilizing a siliconon- insulator wafer. The SOI wafer contains three layers- a 400μm thick “handle” layer of silicon followed by a 2μm thick oxide layer topped with a 20μm thick “device” layer of silicon. The embedded oxide layer acts as an etch-stop during silicon etching, leaving a thin membrane of consistent thickness on the device side. The device dimensions were chosen to provide acceptable membrane deflection predicted by calculations and Finite Element Analysis. A microfabrication process plan was designed to produce thin membranes appropriate for electrostatic actuation. A 700nm layer of …
Lunalight Project: Solar-Rechargeable Led Lantern And Cell Phone Charger, Sean C. Dawson, Michael E. Deagen, Francisco N. Dye, Brian S. Mircheff, Ryan O. Ramelb
Lunalight Project: Solar-Rechargeable Led Lantern And Cell Phone Charger, Sean C. Dawson, Michael E. Deagen, Francisco N. Dye, Brian S. Mircheff, Ryan O. Ramelb
Materials Engineering
Today, 1.6 billion people in the world do not have access to grid electricity. Villagers living off the grid in developing nations resort to kerosene lanterns to light their homes. The fumes from burning kerosene are toxic and lead to respiratory illnesses over time. Our sponsor, OneMillionLights, plans to help people to escape poverty by providing them with a clean source of light at night. Children that must work in the fields during the day can use a solar-rechargeable lantern at night to read or study, and street vendors can use the lanterns at night to improve their businesses.
The …