ECE 498 CL1

Subject offerings of new and developing areas of knowledge in electrical and computer engineering intended to augment the existing curriculum. See Class Schedule or departmental course information for topics and prerequisites. Course Information: 0 to 4 undergraduate hours. 0 to 4 graduate hours. May be repeated in the same or separate terms if topics vary.

Prerequisites: ECE 340. This course explores the energy conversion devices from fundamentals to system-level issues. The modern devices to be explored include light emitting diodes and solar cells. Topics include energy transfer between photons and electron-hole pairs, light emission and capture, emission and absorption engineering via device simulation/design, radiative and non-radiative processes in devices, electrical and optical characteristics, carrier diffusion and mobility, light extraction and trapping, and thermal management for high power high efficiency energy conversion devices.

This course explores the energy conversion devices from fundamentals to system-level issues. The modern devices to be explored include light emitting diodes and solar cells. Topics include energy transfer between photons and electron-hole pairs, light emission and capture, emission and absorption engineering via device simulation/design, radiative and non-radiative processes in devices, electrical and optical characteristics, carrier diffusion and mobility, light extraction and trapping, and thermal management for high power high efficiency energy conversion devices.

This course explores the energy conversion devices from fundamentals to system-level issues. The course starts with a review of the electronic structure of atoms and semiconductors, quantum physics, and compound semiconductors. Then semiconductor heterostructures and low dimensional quantum structures, forming the basis of modern devices such as light emitting diodes and solar cells are introduced. Topics covered include energy transfer between photons and electron-hole pairs, light emission and capture, emission and absorption engineering via device simulation/design, radiative and non-radiative processes in devices, electrical and optical characteristics, carrier diffusion and mobility, and light extraction and trapping for high efficiency devices. Computer labs and cleanroom labs reinforce modern device design and analysis such as light emitting diodes and solar cells.

Classroom Lecture Topics: Approximate Hours:

1. Introduction to Class 1
2. Introduction to LEDs and Solar Cells 1
3. Materials, Physics, and Quantum Structures 2
4. Fundamentals for LEDs and Solar Cells 2
5. Light Emitting Diodes 8

1. Spectral Engineering
2. Radiative and Non-radiative Recombination
3. Electrical Properties
4. High Internal Efficiency Designs
5. High Extraction Efficiency Designs

1. Solar Cells 8

1. Photovoltaic Effect
2. Photocurrent and Quantum Efficiency
3. Dark Current and Open Circuit Voltage
4. Strategies for High Efficiency Solar Cells
5. Light Management/Confinement/Recycling
6. Concentration and Its Effects

1. Thermal Transport 2
2. Project In-Class Presentations 3
3. Review 2

Total: 29

Purpose: This is an advanced course in energy conversion physics, devices, and design technology. The course covers fundamentals as well as modern research topics, and will accommodate a broad range of backgrounds and interests from Electrical and Computer Engineering, Solid State Physics, and Material Science. If you are unsure of your individual preparation for this class, please check with the instructor. A solid knowledge of quantum mechanics, solid-state physics, semiconductors, and familiarity with a numerical computing software (e.g. Matlab, Python) is recommended.

Timeline: There are 41 hrs lectures {29 hrs classroom lectures & 12 hrs hands-on computer lab lectures}, and 22 hrs hands-on experimental labs spread over 14 weeks during the spring semester.

Homeworks (Total Weight 12.5%): Due approximately every week, and some will contain open-ended “research” problems. That is, not all necessary information will be provided up front, you may have to look up constants, material properties, and make reasonable approximations. Some homeworks will involve computational work with Matlab or freeware software available on campus, including numerical integrals, straightforward finite difference problems, and simple device simulation. You may work in groups on the homeworks, although separate write-ups must be submitted. In the Spring 18, there will be 11 homework sets.

Projects (Total Weight 12.5%): The class involves a final project. This will be an open-ended research project of your choice. The report is written following the National Science Foundation (NSF)-style. The details on the project can be found at the project documentation provided. You are encouraged to work in pairs/teams, and to think of topics as the course progresses. However, each student will have one independent project.

Midterm (Total Weight 20%): In the midterm, students are responsible for all subjects covered in the class including blackboard lectures, printed lecture notes, homework reading assignments, and all homework. It will be ONLY 2 HOURS long, from 7-9 pm. We will start at 7 pm in ECEB 2013 and finish the exam at 9 pm. This is a closed book and closed notes exam. You are allowed to bring ONE standard index card (3 by 5 inches) with hand-written notes - you can write on both sides. Instructor will be validating your index cards pre-exam. You are encouraged to write all the fundamental constants (h, pi, electron mass, and so on) into your index card. It is your responsibility to have all the constants and equations ready in your index card. Calculators and rules are allowed. Unless stated otherwise, do your work on the page of the problem and if necessary on the preceding blank page. Be sure to explicitly show the units in your work, as well as in your answers. Circle your answer. Be neat and write clearly! If we cannot read or follow your work, you get zero credit! For each problem, you must show complete work and indicate your reasoning. No credit will be given if you do not show the complete work and describe your procedure, even if the answer is correct.

Final (Total Weight 30%): In the final, students are responsible for all subjects covered in the class including blackboard lectures, printed lecture notes, homework reading assignments, and all homework. It will be ONLY 3 HOURS long, from 7-10 pm. We will start at 7 pm in ECEB TBD and finish the exam at 10 pm. This is a closed book and closed notes exam. You are allowed to bring TWO standard index card (3 by 5 inches) with hand-written notes - you can write on both sides. Instructor will be validating your index cards pre-exam. You are encouraged to write all the fundamental constants (h, pi, electron mass, and so on) into your index card. It is your responsibility to have all the constants and equations ready in your index card. Calculators and rules are allowed. Unless stated otherwise, do your work on the page of the problem and if necessary on the preceding blank page. Be sure to explicitly show the units in your work, as well as in your answers. Circle your answer. Be neat and write clearly! If we cannot read or follow your work, you get zero credit! For each problem, you must show complete work and indicate your reasoning. No credit will be given if you do not show the complete work and describe your procedure, even if the answer is correct.

Grading: Homeworks (12.5%). (Computer) Lab Lectures (12.5%). (NanoFab) Cleanroom Work (12.5%). Project (12.5%). Midterm (20%). Final Exam (30%).

(Computer) Lab Lectures (~12 hrs) (Total Weight 12.5%): Freeware software (BandEng, wxAMPs), and industrial finite element modelling Crosslight software (http://www.crosslight.com/) are primarily used during the hands-on computer labs for the design and simulation of quantum structures, light emitting diodes, and solar cells. There will be at least one formal review in-class lab lecture assignment for each lab set. The weight of each lab is different. The computer lab alternates for lectures as to be posted on a weekly basis (dependent upon the classroom lecture progress).

The select topics of computer lab and their weight distribution are:

(1) (2 hrs) Quantum well simulation (Crosslight software).

• (1.0 %) End of lecture review assignment

(2) (2 hrs) Band diagram simulation of a heterostructure (BandEng freeware software).

• (1.0 %) End of lecture review assignment

(3) (2 hrs) AlGaAs-based light emitting diode simulation (Crosslight software).

• (3.5 %) End of lecture review assignment

(4) (2 hrs) Si-based solar cell simulation (wxAMPs freeware software).

• (2.5 %) End of lecture review assignment

(5) (2 hrs) Si-based solar cell simulation (Crosslight software).

• (3.5 %) End of lecture review assignment

(6) (2 hrs) Thermal Simulation (Crosslight software).

• (1.0 %) End of lecture review assignment

(NanoFab) Cleanroom Work (~22 hrs) (Total Weight 12.5%): NanoFab cleanroom located in the ECE Building is used for the cleanroom activities related to the characterization of light emitting diodes and solar cells. There will be a formal report for each lab set. The formal report will be graded in its due assigned week. The weight of each lab is different due to the varying lab content.

The select topics of NANOFAB lab and their weight distribution are:

Week # 1 {defined as 1^st full week starting with Monday Lecture Class}

(1) (Pass or Fail): Safety Training

Weeks # 2-3

(2) (Weight of 1.5%): SEM Training & SEM Inspection of LEDs and Solar Cells

Weeks # 4-6

(3) (Weight of 2.5%): Identification of leakage paths and loss mechanisms in LEDs

Week # 7-9

(4) (Weight of 3.0%): Effects of temperature on LED characteristics

Weeks # 10-12

(5) (Weight of 2.5%): Identification of leakage paths and loss mechanisms in a solar cells

Weeks # 12-14

(6) (Weight of 3.0%): Effects of temperature on Solar Cell characteristics * Series/Parallel Solar Cells

No single textbook covers all topics. We will rely on handouts, slides, PDFs, and sections from several books including “Light Emitting Diodes” by E. Fred Schubert (Cambridge, 2003) (Lectures III-V) [http://www.amazon.com/Light-Emitting-Diodes-E-Fred-Schubert/dp/0521865387], and “The Physics of Solar Cells” by J. Nelson (Imperial College Press, 2003) (Lectures VI-VIII) [http://www.amazon.com/Physics-Solar-Properties-Semiconductor-Materials/dp/1860943497]. Multiple hard copies of these books are available in the reserve section of the Grainger Library.

Pre-reqs: ECE 340

1/22/2018by Can Bayram