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Dolphin Patel
MSEE, Electrical Engineering, Michigan Technological University

Bio[edit | edit source]

Learning the utter interdependencies of the materials-synthesis-device fabrication is something that has always intrigued me. Having been exposed to cleanroom processes & techniques and reading about problems defining contemporary understanding and future development of electronic materials from the Principles of Electronic Materials and Devices by S.O.Kasap further molded my interest in semiconductor materials. However, it was the experience of working in the microfabrication laboratory and realizing how I as an engineer could make a massive difference by operating at nanolevel reinforced my decision to further my research in these subjects. I would like to contribute to the constant change in paradigms in the field of electronic materials, device fabrication, and solar photovoltaics.

I have completed my Bachelor in Engineering in Electrical Engineering from Gujarat Technological University, Ahmedabad, India which was majorly focused on Power Systems and Renewable Energy. As part requirement towards degree completion, I undertook my final year research project titled Piezoelectric Energy Harvesting and its Applications. During the initial literature survey, I was amazed by the diverse applications of piezoelectricity, and inspired by the idea of Innowattech –an Israeli organization, the idea was to work to generate electricity by installing piezo transducers on a railway track. The project consisted of a working model of a moving train on a piezo transducer installed track, generating electricity from the resulting pressure. My motivation for pursuing graduate degree stems from the challenges faced during this research project be it the selection of material, studying the behavior of materials under different conditions. This governed me to gain more knowledge about energy harvesting. So, I decided to study further on materials for energy applications. This landed me at Michigan Tech to pursue my Master of Science.

At Michigan Tech my exposure to the EE 5430 Electronic Materials made me more interested in electronic materials as my research focus. According to Prof. Elena Semouckina, this was the course that would help students’ understanding of current advances and trends in engineered materials and provide exposure to materials related ideas that can be put to use in next-generation electronics. This changed my perspective of looking at energy materials in general, and I now became more interested in working toward electronic materials. To gain more experience with what I learned in EE 5430, I enrolled in Microfabrication Laboratory. This was one of the most amazing academic experiences I ever had. I got an opportunity to work with Dr. Chito Kendrick, Managing Director of the Laboratory. I worked for 13 weeks with him to fabricate working solar cells out of a 4” silicon wafer. We used standard operating procedures for all the microfabrication processes used. I gained hands-on experience to processes like photolithography using Shipley 1827 PR, doping, ion implantation, annealing, deep reactive ion etching, electron beam deposition on KH Frederick EB12, wet & dry oxidation.

To get more experience of working in a research environment, I undertook an independent research project in fall 2018 with Dr. Joshua Pearce as a part of my research credits. I worked to construct a mathematical model to compute the total solar radiation incident on a reflector-collector system in python scripting. This project consisted of many miniature computational models such as the sun location model, reflector model, collector model. The behavior of reflector-collector system combining all the models was observed, performance on annual as well as the daily basis was studied. I have also developed my knowledge of battery technologies and battery electrochemistry. To put this knowledge to practical use, I designed a Li-ion battery for the DOE Freedom car to meet the predefined goals by DOE. In addition to this, as a part of Advanced MEMS course, I got an opportunity to work on a project based on the literature proposed by NASA JPL. Here we designed a micro-thruster to observe the effects of thermal diffusivity on flame extinction. Quartz, diamond, silicon, and alumina were the materials used for modeling the performance of micro-thruster. This project was under the supervision of Dr. Paul L. Bergstrom. I have also worked as a Course Grader/TA for EE 5430 Electronic Materials under Dr. Elena Semouckina and EE 4240 under Dr. Paul L. Bergstrom

Apart from academics, I am also an active member of Michigan Tech Mind Trekkers. It is a student organization comprising of graduate and undergraduate students who bring STEM to the hands and minds of K-12 students. We conduct various mega events across the country. I’m also a part of Leaders in Continuous Improvement (LCI) LCI- an organization that uses Continuous Improvement and Lean Principles to make both our own lives and organizations better. Owing to my inclination towards teaching, I worked as a teaching faculty at Enbee Education Center. I was responsible for taking TOEFL, PTE classes. In addition to this, I also served as a personal speaking and writing coach, mentoring students who needed one to one interaction and attention.

The semiconductor industry lives- and dies- by a simple creed: smaller, faster and cheaper. I aspire to work with materials that increase the performance of the system, at the same time reducing the cost of the fabrication. I believe that I will bring with me innovative and distinct thinking, diversity, and the unique advantage of having studied two different yet synergistic fields.

Skills[edit | edit source]

Semiconductor Microfabrication Cleanroom Processing Photolithography
Etching - Wet and Dry Dopant Diffusion Thin Film Deposition-CVD & PVD
MEMS Design Battery Electrochemistry Battery Technologies
MATLAB Python COMSOL Multiphysics
Statistical Process Control (SPC) Design of Experiments (DOE) JMP
KLayout Minitab Solid State Physics
PV Modelling Fuel Cells MS Office

Project Experiences[edit | edit source]

Design of Low-Concentration Solar Photovoltaic Systems in Sub-Optimal Orientations[edit | edit source]

Optimally oriented solar photovoltaic (PV) systems have shown substantial increases in energy yields with modest concentration in both simulation using a wide array of models and field experiments. However, many smaller PV systems as with those retrofitted on existing rooftops are sub-optimally oriented and tilted. This study provides an open source python-based program that couples 2-D and 3-D models for the design of a flat-plate PV collector augmented by a flat-plate reflector attached a the lower edge of both. The shading from the reflector on the PV is taken in to consideration as well as diffuse radiation. The mathematical models were validated from past results and then the new coupled 2-D and 3-D models are used to find the optimal reflector positioning for a range of locations through out the United States based on the sensitivity analysis performed on tilt angle of the reflector, surface azimuth angle and latitude of the PV system. The enhancement in the average annual energy absorbed is simulated for locations for non-optimized orientations and found to be in the single to double digits. Future work is necessary to find a reflector that is economically viable for such low concentration PV systems.

Mathematical Model to Compute Total Incident Specular Solar Radiation[edit | edit source]

This work was a part of my research credits. I undertook a project titled “Mathematical Model to Compute Total Incident Specular Radiation”, it was an independent research study under Dr. Joshua Pearce. I worked to study the calculation of incident specular solar radiation from the reflector on to the collector module and to model it mathematically using python scripting. Carried out a great deal of literature survey from articles and papers on augmented reflector-collector systems and learning their performance. My responsibilities included constructing models to compute the angles that can predict the sun’s location during any time of the day any time of the year. The radiation was modeled in four different cases shadowing, full acceptance, partial acceptance, and total miss. The prospects of this project are to evaluate the radiation when the and the collector are horizontally separated at a certain angle. As a part of stage one, modeling is completed, and we are looking forward to experimenting to validate the results of this model in the next stage. ( Sep 2018- Dec 2018)

Design of a Positive Electrode of a Lithium Cobalt Oxide Battery for DOE Freedom Car[edit | edit source]

The project was aimed to design a LiCoO2 battery for vehicle battery system for DOE freedom car. The goals were modified and predefined by DOE. Relationship between internal resistance and separator area was observed. Various performance parameters such as separator area, porosity, radius of the particle, thickness of the electrode was optimized and modeled in order to meet the modified DOE Freedom car goals. The effects of aging on internal resistance, capacity and available energy was determined. (Sep 2018-Dec 2018)File:Project dolphin vbatt.pdf

An Approach to Alleviate Intermittency in the Distribution System Using an Ultracapacitor[edit | edit source]

This project focuses on the grid intermittencies such as sag and swell, and an approach is proposed to mitigate the intermittencies by employing ultracapacitor as an energy storage system. A model was designed in Simulink, integrating ultracapacitor to the dynamic voltage restorer. Bidirectional DC-DC converter was used to merge ultracapacitor to the dc link of the dynamic voltage restorer.(Jan 2018-May 2018)

Impact of Thermal Diffusivity on the Flame Extinction in Microthrusters[edit | edit source]

Behavior of materials like silicon, alumina, diamond, and quartz were observed under the effect of temperature and the performance of the thruster was modelled using COMSOL Multiphysics. This project was based on the experiment at NASA’s jet propulsion laboratory. A microthruster was designed and different materials were tested based on the capacity of the material to withstand the heat inside the thruster. Diamond was determined to be the best of all the materials selected that can withstand the heat and generate enough lift-off.(Jan 2018-May 2018)

Fabrication of Solar Cell on 4" Silicon Wafer through Micro-fabrication processes and Techniques[edit | edit source]

  • Microfabrication Facility (MFF) is a research facility, which empowers students in micro and nano-scale research, solid state electronics, micro-systems materials, and devices. Worked at MFF with Dr. Chito Kendrick, Managing Director to develop solar cell through microfabrication processes.
  • This project included the processes— RCA Cleaning, Wet and Dry Oxidation, Wet Etching, Photolithography (used thrice), Dry Etching- DRIE, Dopant Diffusion, Thin Film Deposition. The processes went on for 13 weeks, starting from wafer cleaning to Device testing.
  • Experience in RCA Cleaning using the SOP.
  • Experience in wet oxidation.
  • Experience in Photolithography using Shipley 1827 PR and developer MF 319.
  • Experience in Wet Etching, Mask alignment.
  • Experience with DRIE using TRION.
  • Experience with dopant diffusion with phosphorous(SOD-P-507).
  • Worked on Frederick Electron Beam Deposition Tool (KH Frederick EB12) for Thin Film Deposition. Deposited Aluminium on the back side of the sample wafer for back contacts and gold, chromium and silver for the top contacts. The top contacts were fabricated using a different tool.
  • Developed a process flow for MOSFET Fabrication.
  • Gained practical experience of cleanroom and all the microfabrication processes. (Sep 2017-Dec 2017)


Areas of Interest[edit | edit source]

  • Semiconductor Processing
  • Solar Cell Fabrication
  • PV System Design
  • Microfabrication
  • Battery Technologies and Design
  • MEMS
  • Electronic Materials
  • 3-D Printing Electronics

M.S. Coursework[edit | edit source]

No.# Course Instructor Grade
1. Electronic Materials Dr. Elena Semouckina AB
2. Introduction to Micro-electromechanical Systems Dr. Paul L. Bergstrom BC
3. Microfabrication Laboratory Dr. Chito Kendrick A
4. Energy Storage Systems Dr. Lucia Gauchia AB
5. Advanced Micro-electromechanical Systems Dr. Paul L. Bergstrom A
6. Solid State Devices Dr. Elena Semouckina AB
7. Materials for Energy Applications Dr. Yun Hang Hu A
8. Vehicle Battery Cells and Systems Dr. Stephen Hackney A
9. Mathematical Model to Compute Total Incident Specular Solar Radiation (Research Credits) Dr. Joshua Pearce AB
10. Solar Photovoltaic Science and Engineering Dr. Joshua Pearce A