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12/11 It is completely fine for you to turn in the term paper prior to the deadlinie, if you have a personal schedule conflict. In fact, I started receiving submissions. -TY

12/11 The term paper is due on 12/13 as announced before. As explained before, authors have only one chance to revise in refereed journals. In this EE227, you are already given my feedback multiple times in the abstract and oral. Thus, you have more feedback compared to it. This may sound like a circular logic, but if you want to respond to referee's comments effectively, you have to be a productive scientist, so that your revision can convince referees. I hope this will give you an insentive to study science so that you can be victorious in the debate with tough referees. -TY

12/5 For the term paper, you can use my personalized suggestions for the abstract and slides. If you work in a project in a graduate program, you will submit an abstract, talk in a conference, and submit to a refereed journal. You want to use the same logical structure for the final paper, possibly with some revisions through your experience from your talk in a conference.

If you want to see specific examples for review papers, you can look at Review of Modern Physics. Then you can find examples.

Generally, your term paper should report a new device and/or material. Thus, you want to: 

- Explain the traditional device or material. Clarify the physics.

- Introduce the new device or material.

- Give scientific discussions.

In yesterday's presentations, you have witnessed many examples. You want to learn from good presentations. -TY

12/5 Thank you for your hard work in oral. This is similar to Am Phys Soc Meeting format, and in a sense a reminder of a shot gun session in the old days. The next and the final project is the term paper due at 10 am, 12/13 (Thu). I think my personalized suggestions to each individual for the abstract and slides are similar. You would want to write a perm paper having them in mind. All of my advice for the abstract and oral will apply to the perm paper-TY

12/4 Oral presedntation today. You want to be familiar with local rules. -TY

12/3 I will give personalized suggestions once for everybody. You will make a revision. But I don't give 2nd or 3rd round suggestions. -TY

12/3 Let me explain how the slide submission is planned since there is some misunderstanding. The process follows the review process of a refereed journal. In Appl. Phys. Lett., your work is reviewed by a referee. He or she will give you suggestions. You are given only one chance to revise. Then the referee will make a final decision. You cannot do this multiple times in a professional journal. What I am offering is if you think your first revision is not perfect from your view point, you may submit a revision again by 11 am tomorrow, but you cannot get my feedback anymore.

12/2 I have to advise almost the same thing to everybody.

- If you need to present traditional device A with a new material B, you need to explain device A and material B using energy bands and/or E-k.

- You don't want to tables or equations, they don't add anything if good plots are provided.

- Still many people forget references.


12/2 I will add comments on this web page, and if you really need to revise, you could do so multiple times if that's before 12/4 11 am. If you write a technical paper, you have only one chance to revise, and if the referees don't like your revision, it is over. But this is too tough in a classroom, so I accept a revision up to twice. -TY

12/2 Please don't forget references, otherwise, people think you stole data. -TY

12/2 I started receiving slide submissions, but very often I cannot read files (strange truncation, etc). Please use a standard pdf. If there is a problem at the conference, you may lose your presentation, the Chair doesn't have any responsibility for file readability. -TY

12/2 After I receive your first slides, I will give you my receipt and a feedback. In principle, I will not give you further feedback but you would want to resubmit the revised version. The deadline for the revision is 12/4 (Tue) 11 am. Basically, the following is my common advice. If this is your first time to give an oral presentation, you want to turn in earlier, so you can have more time for revision. If you have had enough experience, follow your standard schedule. 

Basically, the following is my common advice.

(1) This is not a business presentation. You need to discuss science, and the easiest way is to involve an energy bands and appropriate schematic plots.

(2) Limit the number of words and equations. Another way to say the same thing is to use figures effectively.

If you need examples, look at my lecture notes. Good luck. -TY

12/1 Lecture notes uploaded. -TY

11/28 Slides due on 10 pm, 12/3 (Mon). Here are suggestions. The three elements are (1) Introduction: clarify the device and/or material. (2) Introduce a topic. (3) Discuss physics. You do not want to place too many topics. Make sure you let the audience learn something in science. -TY

11/28 HW5 sol posted. There is no need to submit, but HW6 problem and solution are posted for your study. A p-type dopant is group 3 and has 3 electrons when neutral. When ionized, it accepts an electron and create a hole. An n-type dopant is group 5 and has 5 electrons when neutral. When ionized, it donates an electron and is positively charged. Very simple addition/subtraction. Very simple math and deep science, 5 - 1 = 4 for donors and 3 + 1 = 4 for acceptors. -TY

11/25 In the Boltzmann formalism, v must be an Ensemble average <v>. It is zero and reaches  steady state value in the end. -TY

11/24 Midterm grading: one question = 6 pnts max. Since there are 12 questions, the theoretical max = 72. Bonus is given if you are the only one person who has the correct answer. A lot of misunderstanding for energy bands and mock experimental analysis, which I will explain in class. The final presentation is still 65 %. Thus, everybody has a chance for good respectable grades. -TY 

11/24 Oral schedule on 12/4 (Tue). You will submit your slides and Chair (Yamada) will controle them when you present (you will say nest please). Please don't be late. Every thing on time.



Md Nafiz


























11/24 Midterm returned. I will go over the exam on the next Tue. -TY

11/23 HY5. Tau is the collision time. The Newton Equation reads

   mdv/dt = qE (force from the field) - v/(tau) (friction)

This tau characterizes the friction having the dimension of time, and is called collision time or relaxation time. Thus, mobility = q x tau/m, which is very reasonable since less traffic accidents (long tau) and less weight result in large mobility. -TY.

11/19 Correction question 4. -TY

Correct: a real triangular function and is 0 at x = 0 and a, while it is 1 at the midpoint of [0,a].

11/19 EE227 schedule (tentative).

12/3 (Mon), 10 pm, Oral slides due.

- Up to recomended 5 (abs max = 6 pages), including top and last pages.

- Template available below.

12/4 (Tue), 5:20 - 6:55 pm, Oral presentation of all 12 people.

- 6 min/person + 1 min Q @ A by the Chair (Yamada).

- Close to Am Phys Soc Meeting presentation schedule format.

12/13 (Thu), 10 pm, term paper due.

- Up to 3 camera ready pages using EDL template below.

11/19 Question 4. "Draw four periods" mean plot for [0,4a]. -TY

11/17 Error correction for question 4(1):

     Wrong: ... while it is 1 at x = 1/2.

     Correct: ...... while it is 1 at x = a/2 (i.e., the middle point of [0,a]).

11/16 Midterm was sent at 1 am via email. If you have not received it, please contact me immediately. Good luck, and have a safe weekend. -TY

11/14 You probably put too many elements in this abstract. In the oral, you can have only several slides with several minutes, so you need to restrict your topic. You would want to choose a topic (restrict a topic) and present. -TY

11/14 If you need to make changes, please resubmit your abstract. No official deadline for your second submission, at your earliest convenience. -TY

11/14 The title is now considered as the shortest abstract, and descriptive titles are more and more popular. -TY

11/14 You want to concentrate on the device physics of Si detectors. You can basically remove all related to other subjects (I know this is your main interest, but keep it for other courses). The main player here is Si detectors in EE227, and you need to adjust your presentation. -TY

11/14 You want to choose one technical point and discuss deeply, so that the audience can learn something after your oral presentation. This is possible only when you have a strong focus. -TY

11/13 Choose a focus and go deeper. Please don't scatter. -TY

11/13 Generally, you want to write down all authors in the reference. If running out of space, consider renoving the reference systel. -TY

11/13 Regarding abstract references, if you use somebody's results, then you must cite his/her paper(s). If you don't do it, then you will be criticized (you stole others' results). Thus, unless that's your new results, you will cite references usually. -TY

11/12 Regarding the abstract, please choose a topic and go deeper. Please do not give a presentation that covers many topics in a shallow way. You need to have a clear focus. -TY

11/12 The author of the abstract must be you. You are going to present a paper (papers) in EE227. -TY

11/12 I received a question for references in the abstract. If you are submitting for a conference, the committee is going to decide (1) oral, (2) poster, or (3) reject depending on your abstract. Thus, if you have your own relevant publications, it is better to cite them. Having said that, it is up to you what to do references in this EE227 abstract. -TY

11/11 Class notes for week 5 and week 6 uploaded. Hope you have a safe weekend. The air polution was terrible yesterday... -TY

11/8 HW5 deadline extended to post-Thanksgiving 11/27 (Tue). The calculation memo for infinite period potential uploaded. If your emphasis is in modeling and simulations, please study it thoroughly. If your emphasis is in experiments, you can concentrate on the final results. The updated schedule: Abstract due on 11/14, Midterm (distribution on 11/15) due on 11/20, HW5 due on 11/27. -TY

11/6 HW4 sol and HW5 due on 11/13 (Tue) uploaded. An example for abstract uploaded. This is a real abstract I submitted to the MRS. You may use this as a template. Templates for slides and term-paper are also uploaded. Abain, the paper is a real one for the IEEE EDL. -TY

11/3 Regarding the one-page abstract for your final presentation, I am temporarily looking at 11/14 (Wed). Based on your abstract, I will give you my feedback to your selection of topic. Thus, the abstract is counted for your grade only when your grade goes up (if your topic is inappropriate for EE227 and you are suggested to choose a different topic, then the abstract is not counted for your final grade). -TY

11/3 The midterm schedule: distribution on 11/15 (Thu) and submission by 10 pm on 11/20 (Tue) . Please compile your answers to a fingle file. -TY

11/2 Some people wrote to me regarding the research proposal (abstract) for final presentation. By no means, the abstract due date is not this week. I will let you know at least a week advance regarding the abstract due date. -TY

10/31 HW3 sol posted. HW4 due at 10 pm, 11/6 (Tue) posted. We have examined the Bloch theorem, and now move into minite potential cases. Clever use of Heisenberg principle is the key to understand the behaviors of an electron. -TY

10-27 Class notes for weeks 3 @ 4 uploaded. -TY

10-26 We have examined the Bloch theorem. By knowing the momentum and the wave function in cell 1, we should be able to know wave functions in cell, 2, cell 3, etc., successively. This means in zincblende, we can just study only two basis atoms and we know the entire crystal. -TY

10-23 For those interested in EE227 for graduate exams: please study the following subjects, (1) energy bands (2) basic quantum (3) crystaline structures. You can prepare using HWs and/or the midterm exam. -TY

10-23 HW2 sol is posted. HW3 is posted, due at 10 pm on 10-30 (Tue). -TY

10-16 I think I have received HW1 from everybody. HW1 sol is posted, please compare with your answers. HW2 is posted due on 10-23 (Tue). We are examining the 1D quantum well using quantum. -TY

10-13 Class notes for weeks 1 @ 2 uploaded. -TY

10-12 We have started quantum and are looking at 1D quantum wells. -TY

10-10 There are only two semicond structures, zincblende and wurtzite (except for advanced low dim materials). Zincblende has ABCABC and wurtzite has ABAB, but other properties are very similar. In this EE227, we examine zincblende exclusively as most three-five are of zincblende. -TY

10-8 We have examined diamond and zincblende. Thre are two basis atoms and there are 8 outermost electrons. In either case, we have 4 electrons per atom. The diamond or zincblende will guarantee there 4 nearest neighbor atoms, and all electrons are used for chemical bond formation. This makes the crystal structures semiconducting. HW1 uploaded (please log in with your blue ID), due at 10 pm, 10-16 (Tue). Please scan your answer sheets (limit the file size) and submit via email. -TY

10-4 We have studied lattice and basis. -TY

10-3 You can download files at the bottom of this page, after you finish loging in at the bottom (you even cannot see files if you don't log in). -TY

10-2 We have discussed capacitor, dielectric function, and three material states related to band gap. -TY

9-27 Hi, welcome to EE227 Sec 01 and 50. We have discussed capacitors in nanoscale materials, and often they are linked with quantum capacitors. Coulob blockade is one extreme case involving ultrasmall capacitors, beyond quantum capacitors. If there is 1 V by using a unit charge of 1.6 x 10^(-19) coulomb, the capacitance is 10^(-19) farad !!! -TY

Fundamentals of Semiconductor Physics

Welcome to EE227, Fundamentals of Semicond Physics, Fall 2018. We have learned Solid State Physics and Devices multiple times. But in many cases, the connection to traditional Electromagnetism or other fields of Physics is not discussed. For example,

(1) Dielectric Constant (function) ε

Many books say it increases a capacitance value by ε when a dielectric is inserted. OK. If we have to consider ε for a metal, which value is the most appropriate? Quick answer: minus infinity. Why?

(2) E-field and D-field

If an electric field is applied to a material, it will be polarized, which is E and which is D? Quick answer: the input external field is D and the output field is E. The common sense is the other way around. What is going on?

(3) Quantum Capacitor

As a device, a capacitor has two terminals. Each terminal is connected to an electrode, and a pair of electrodes store positive and negative charges. But the new concept of quantum capacitor applies to a single conductor storing only one kind of charges. What does it mean?

(4) Energy Bands

In some textbooks, it is written, "the bottom of the conduction band is s-like, and the top of the valence band is p-like." Wait a minute. P-orbitals must be higher in energy than s-orbitals. What is going on? Quick answer: this is not a typo and is correct. There is a deep meaning for it. 

If you are like me, you may have spent a lot of time considering these subjects. The course will cover subjects that may be familiar to you, but there are often twists. We will re-examine various fundamentals and clear up annoying paradoxes. New concepts are also covered, such as Coulomb blockade, various tunneling, double layer capacitance, pseudocapacitance, etc.

Rather than concentrating on mathematics, we really want to understand what is going on in semiconductor materials and devices. If you have any questions, just send me an email at tyamada@soe.ucsc.edu.

You may look at T. Yamada, Chapter 7, "Nanoelectronics Applications" in Carbon Nanotubes: Science and Applications edited by M. Meyyappan, (CRC, Boca, Raton, 2004). But it was written ten years ago, and new topics such as quantum capacitor or kinetic inductor are not discussed. They will be surely covered in class. Syllabus is available in "Attached Files (Secure)" in the left column. Please check "Class Guide (Secure)" regularly, since all announcements are made in there.

***Important****Please click Class Guide (Secure) regularly with your BlueCruz ID, since all important communications are posted there. HWs and class notes are posted in Attachments, but again you need yourBlueCruz ID.


Toshishige Yamada, Ph.D. (EE)