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12-11-17 I have enjoyed EE227 in Fall 17 for the first time since I am back. There are a lot of questions in class, and an appreciable portion of my lecture is based on  the interaction with you. Especially, I did not plan an extensive coverage for energy bands at the beginning, but in response to active questions from you, I started a lot of discussions on the subject. I hope you can draw energy bands for fundamental devices by now. -TY

12-11-17 I have received everybody's term paper submission. Thanks for your hard work. -TY

12-11-17 The deadline for the term paper is at 7 pm tonight.  -TY

12-10-17 I had a question for how to cite a figure, and this is my reply.

If this is an official paper, you can write Fig. 2 taken from Ref. 7 (permission obtained from the authors of Ref. 7).  This involves some legal processes, and our responsibility is to contact the authors and obtain permission. Of course, we need to respect the authors' decision. Some of them don't want to give us permission, and in that case, we need to give up citing the figure. After obtaining permission, specific legal terms must be used. That's usually taken care by the journal office (an attorney of the journal office because it is related to copyright law). The term paper will not appear in the public domain, so we just cite Ref. 7 for Fig. 2. -TY.

12-9-17 I am getting a term-paper submission. This is my message for one person.

This is just my advice, usually if you write over the designated length, your paper will be rejected for that reason. This is true whenever you submit to a letter journal such as EDL, APL, or PRL. You really don't want to risk your work for this kind of non-scientific issue... -TY

12-7-17 I am planning to teach at UCSC main campus. See you tomorrow. -TY

12-6-17 The first half presentation is over. You may have realized it takes more time to finish. That is why I said 5 pages at the bebinning. Focusing is also very important. Without the focus, again you are running out of time. In answering a question, you want to vie a one-phrase answer. See you on Fri. -TY

12 -6-17 Today is a presentation day. (1) Arrive with a reasonable time margin. If you are late, you lose your presentation privilege. (2) Follow local rules. Usually there is a remaining time warning. See you in class. -TY

12-4-17 Please do a rehearsal and make sure your talk will fit to 8 min. The Chair must stop at 8 min no matter what. To shorten time, you must decrease the number of topics. The same advice of "focus, not scatter" applies. -TY

12-3-17 I started receiving slides. I have lifted the page restriction, but I will personally warn you if the number of pages is unreasonably large and I sense that you cannot finish within 8 min. Please keep in mind that around ~7 min, the Chair will say "please wrap up", and you have to finish. I strongly recommend to do a rehearsal and measure how long it takes. The example I discussed in class has 17 pages and would be a 30-40 min talk. -TY

12-2-17 In slide preparation, you don't need superhigh resolution figures. Please limit the file size to be less than 10 MB (the smaller, the better) so that the system doesn't crash. -TY

12-1-17 In class, I discussed extensively how to prepare slides using examples. I discussed solar cells, and showed introduction, body, and (summary and) discussion. In the evaluation, your talk will be judged by these three points, in addition to clarity and technical validity. Quite often, figures, rather than words play a critical role. The term paper will be evaluated in the same way. The same advice applies. -TY

11-30-17 HW6 and sol posted, NO NEED TO SUBMIT, they are for your study (that's why sol is posted at the same time), please concentrate on slide preparation. -TY

11-29-17 Suggestions for slides. (1) Please assume professional scientists and engineers as audience. (2) In class, I said about 5 patges. If you include a title page, please exclude it from page counting. (3) Introduction must be technical, and you want to explain how the device works, why the material is unique scientifically, rather than discussing history. (4) You really want to let readers learn something technical. (5) Summary should be concise as a page. Timewise, it varies depending on how much time you leave.. The following is a long presentation of 17 pages, and is a good example for what I have discussed so far https://www3.nd.edu/~gsnider/EE698A/hengyang_Photodetector.ppt (The file also uploaded). You would want to create a shorter version of this. -TY

11-29-17 The midterm was returned. The final grade is determined via HW, Midterm, and final projects. If you do quite well in either Midterm or Final projects (idealy in both), that should be rewarding. The number of slides may be up to ~ five to fit to 8 minutes. -TY

Oral slides: 12/4 at 7 pm.
Oral presentation: 12/6 and 12/8.
Final term paper: 12/11 at 7 pm.

11-25-17 Regarding Abstract and Paper, there was a question for how to write a new idea part. If you can introduce materials/devices with our own words, that is already a good contribution in science. May seminal work starts this way. Thus, try to explain with our own words, without borrowling phrases from reference papers. -TY

11-22-17  Here is a "tentative" schedule for oral presentation. People talking on 12/6 will get x % of bonus points (compensation for the less preparation time, x ~ several % to be determined later). One person has 8 min (with Q & A) and this is exactly the format for the Am Phys Soc March Meeting. There is a 2-min break between talks 4 and 5. 

11-22-17 I am grading the Midterm. There are some comments. (1) Don't write anything which is technically incorrect. I am trying not to punish you here, but generally, especially in journal paper writing, if you write anything incorrect, you will be punished. The best way is to shut up, and discuss only cure things. (2) Don't write the final answer only. Don't write an unreasonably long answer. You need a balance, and reviewers or graders are impressed if you show a good balance. -TY

11-22-17 Friendly schedule remainder. -TY

Finalized abstract: 11/27 at 7 pm.
Oral slides: 12/4 at 7 pm.
Oral presentation: 12/6 and 12/8.
Final term paper: 12/11 at 7 pm.

11-20-17 I sent Midterm receipt around 5 pm. The next receipt time maybe around 6:45 pm. -TY

11-19-17 There was a question for complex numbers. If z = 1+i, then we can say the magnitude is sqrt(2) and the arg is 45 degrees, intead of saying 1 and i. This is the polar coordinate representation. -TY

11-19-17 Lecture notes are updated, and they are all placed at the end. -TY

11-18-17 I have distributed the exam questions. If you do not receive them, please let me know immediately. -TY

11-17-17 I will distribute the exam equestions via email today. Please return our answer sheet by 7 pm, 11/20 Mon. -TY

11-17-17 Somebody sent me slides. This is my reply. -TY

Technical contents are good, but I am afraid it takes 30 - 60 minutes to present. You want to reduce the number of figures and equations. I know that it is very painful to cut something you have studied and prepared, but if you are running out of time, the chair will stop your talk in the middle, which you never want. -TY

11-13-17 The HW deadline is basically the next Wed. There will not be HW assigned on 11/15 because of the midterm during 11/17 - 11/ 20. -TY

11-13-17 Midterm reminder: problem distribution 11/17, submission by email 11/20 at 7 pm. -TY

11-09-17 HW4 sol posted. HW5 due on 11/15 Wed posted. -TY

11-08-17 There were questions. (1) For a finite well, we choose a sinusoidal wave function for the well part and the exponential for the barrier part. Why? This is because E -V = E > 0 in the well part (traveling wave) and E  - V < 0 in the barrier part (decaying wave).  (2) How is the k-value measured when the conduction band minimum is different from (000)? When the minimum of the conduction band is different from the gamma valley, the momentum must be measured from the energy minimum point. Please use this rule, and then you will find all figures are consistent. -TY

11-07-17 I am giving suggestions. They are suggestions, and not authorizations or permissions. Whenever you want to change your mind, please feel free to do it. This is similar to a "reply to reviewers' comments" in the peer-review jpurnal reviews. You will make a final decision. -TY

11-07-17 Tempolary schedule. If anybody has a conflict. please let me know immediately. -TY

Midterm: problem distribution 11/17, submission by email 11/20 at 7 pm.
Finalized abstract: 11/27 at 7 pm.
Oral slides: 12/4 at 7 pm.
Oral presentation: 12/6 and 12/8.
Final term paper: 12/11 at 7 pm.

11-06-17 I uploaded an EE227_math_note. All math derivations are discussed in there. Thenote is originally a lecture note in a different university. -TY

11-06-17 After you decide your topic, you want to find one focus, and create a logical flow to that focus. The logical flow must be clean and clear. You may have read multiple papers and gathered a lot of information, but do not have to use all. For the best logical flow, you want to find the best logical flow to present. -TY

11-06-17 Editorial suggestions for the abstract. -TY  

(1) If you cite Refs. 1, 2, and 3, you have to cite in that order, which means do not cite 3, 1, 2.

(2) Please use an appropriate abbreviation, Phys. Rev. in stead of Physical Review. You can check examples on the internet, and you want to follow the community standard.

11-05-17 I am receiving topic emails. What you wanto do at this stage is to determine the topic (material or device) and then outline what you wanto to discuss. For example, you have decided a new material CCC. Additionally, you also want to say you will discuss the propertiy of DDD in the final presentation, wchick is supposed to be very small. As expected the secret is in the structure of CCC. You want to present a clean clear logic for this. -TY

11-03-17 Administrative accouncement. 11/10 Fri and 11/24 Fri will be holidays and we do not meet. We will meet the other days.

11-03-17 There was another submission of an abstract draft. My following comments would be useful to everybody, so let me reproduce it here. -TY

11-02-17 If you have not done so, please email me your choice of final presentation topic by 11-06-17 Monday. I will give you my feedback. You also want to work on the first version of abstract. Please send my an abstract version 1 for me feedback. The final presentation is in December, so please keep that in mind. You will submit a finalized abstract by mid-later November (I will let you know the deadline). -TY

11-01-17 Regarding the final presentation, I suggest you try a new topic (topic you have never worked before) whenever you can. We are like a chef, and it is mandatory for us to increase menu items. If we can cook only one dish, that's not good... In the same way, we should be comfortable with multiple topics. -TY

11-01-17 The lecture note 10-20 to 11-01 uploaded. -TY

11-01-17 HW4 posted. HW3 sol will be posted tonight. -TY

11-01-17 Some people reported an EE227 webcast problem. I have reported it, but if you watch webcast often, you could contact the webcast group, where their email would be webcast (at) ucsc.edu (at must be @), please double check by yourself. If the problem is reported by multiple people, it will be fixed more quickly. Updates: a reply from the IT dept is shown below. -TY

Thanks for the thorough response. I spoke at length with our Engineering group who manage the classroom systems and the issue arose with our switching system behind the scenes in the classroom that required a system reboot. The issue originated with the connection of the document camera to the installed switcher. This has been fixed, and both they and I will both be remotely monitoring the system at 2:40 pm when your class begins.

10-30-17 There was a question for the phase of a wave function. This is my reply.

- I want to consider the wave function has a meaning only in the evaluation of physical quantities. 

- Thus, the phase does not matter if an electron density is concerned in may cases, but there are some pathological cases. In the Aharonov Bohm effect, an electron wave splits into wave 1 and wave 2 and then they reunites. At the reunion point, depending on whether wave 1 and wave 2 have the same phase or not, the electron existence probability changes. In this sense, the electron wave can influence the final result and is measurable.

- In plotting a wave function, we don't pay attention to the amplitude since we do not pay attention to normalization quite often. 

10-29-17 Some of you have started submitting an abstract. The most accepted rule is to cite references. If you have three references (1), (2), and (3), then you must cite them inside your writing. such as "... to characterize transport with high speed measurements (1). Theory is develoed in Ref. (2) and ... However, a new interpretation is proposed in Ref. (3) ..." Thus, references will play a vital role in youir abstract. -TY

10-26-17 There was a question for the final term paper format. You can report on a single paper, or compile multiple papers in your final project. In either case, you could want to develop your own view in a technical subject you choose. The entire surpose of this project is to give you neccesary foundations for your future research. Generally papers are classified into seminal research papers and review papers. Our papers will be classified into the latter, but if you want to give some "research like fravor", that's possible by showing your own view. -TY

10-25-17 If you read papers (or even textbooks) in a critical way, you are close to your own new paper. An effective way to start a paper text is to say "It is believed that X = A as discussed in [3]. However, our experiments show that X is in fact B, not A. In this article, we consider ..." You would know the impact of this introduction. In EE227, you need to read papers. Please read critically, and hopefully establish your own view, which may not be consistent wuth papers you are reading. If you can do it, your EE227 project will be a big success. 

10-25-17 HW3 posted. HW2 due on today. -TY

10-21-17 Some of you have already started contacting me regarding the final presentation topic. I am very happy to give you my feedback individually. The general guide line is (1) choose a key topic and concentrate on it, or "deep" rather than "scatter", i.e., you want to write a scientific review, and if you want, you can even criticize a published paper (in fact, this is quite often how we come up with a new paper idea)! Of course, appropriate introduction is necessary, but you don't want to copy the Wikki, (2) your emphasis must be scientific, i.e., considerations for economic impact are important in our society, but are certainly not our interest in EE227. -TY

10-20-17 EE227 lecture note 9-29 to 10-20 is uploaded. Regarding the final project and midterm, please watch today's video if you were absent. I explained in detail. -TY

10-19-17 I have sent a HW1 receipt and posted its sol. If you haven't got it, please let me know immediately. We will continue quantum for a while. -TY

10-18-17 I have posted files related to the final presentation. The reason is to give you a jump start. In the final presentation, you will present a report for a paper you choose. You can choose your faborite topic of your own. If you don't have any preference, you could choose it from EE227_syllabus2_further references.doc. You (1) write a 1 page abstract (I will give you some feedback, e.g., if your topic is not appropriate to EE227, I will suggest my recommendation), (2) give an oral presentation, and (3) write a term term paper with the EDL (IEEE Electron Device Letters) format up to 3 camera ready pages. The abstract is a typical MRS (Mat Sci Soc) format. The real presentation in MRS or APS (Am Ogts Soc) meeting or AVS (Am Vac Soc) meeting is ~8 - 15 min including Q & A sessions. This is a one cycle you will experience in a realistic research work. The only missing element is to the communication with the reviewers. Please be get prepared. -TY

10-18-17 I will decide what to do for the midterm soon. Considering that quite a few people in class are taking EE227 in the pass/fail basis, I am more inclided to place a higher weight for the final presentation (abstract, opral talk, and term paper). -TY

10-18-17 HW1 is due today. HW2 is posted, due on the next Wed. -TY

10-16-17 We haven't determined "A" in quantum yet. We will determine it using the wave function normalization condition. -TY

10-16-17 There was a question for HW1. The zincblende is made of two kinds of atoms. You want to show the locations of atms A and atoms B, respectively. If we pay attention to the atomic locations only, then the zincblende is the same as the diamond. -TY

10-14-17 We are moving into Quantum Mechanics. A simple 1D square potential model is used in this class to describe a molecule. Historically, this is the potential which Dr. Leo Esaki used in his analysis for superlattices. -TY

10-11-17 HW1 posted. Please submit by the next Wed, which is Wed 10-18-17. You will scan your answer sheet and send to tyamada@soe.ucsc.edu. Because only the submission is recorded, you don't need a high resolution. Please limit the file size. See you on Friday. -TY 

10-11-17 We are studying the Miller index and gradually moving into quantum.

10-7-17 We have studied the zincblende (or diamond if one kind of atoms used) structure. It has 4 near rest neighbors. When Si atoms are used, then all outer most electrons will be used for chemical bond formation. That makes the crystal semiconducting. -TY

10-5-17 Starting tomorrow, videotaped lectures will be up and running (the first few sessions maybe missing or maybe uploaded later). Please get the login info in the secured file below. -TY

10-4-17 Gradually, we are moving into quantum. Why there is a band gap is a bid them. We will study periodic potential + wave nature of electrons = energy band. -TY

10-3-17 There was a question for quantum capacitamce. Electrostatic capacitance needs two conductors, but quantum capacitance needs only one and I did not clearly point out, but BALLISTIC transport is mandatory. Quantum capacitance is highly pathological. We will discuss it later in this course. If we measure it, we have to depend on LC resonance, so we cannot know each contribution separately. -TY

10-3-17 Videotaped classes are available at  https://webcast.ucsc.edu/ (asking a repair now). -TY

10-2-17 I have uploaded a syllabus at the bottom of this page (you may need to log in). You can find reference books and papers. The contents are just a plan, and I will make a final adjustment looking at your faces. Thus, depending on your feedback and responces, the detailed topics will be subject to change. I am checking how to access the videopated lectures. Please wait for the info. -TY

9-29-17 We have started the course for F2017. Everything will be posted here, so please make sure you have an web access. If there is any login problem, please contact the IT department for help. I will spot my lecture notes. Let's get used to the lecture cycle. -TY 

Fundamentals Of Semiconductor Physics