Literally the best lecture on semiconductors I've ever seen.

I used to work at IBM making microprocessors. When you described the MOSFET gate operation, I was reminded of how much time our engineers spent perfecting the gate oxide layer. There were 40 PHD level engineers working full time on gate oxide quality. Good oxide equals faster speed. The more expensive fast CPU processor is identical to the cheaper CPU except for the quality of the gate oxide.

The clearest explanation of how transistors work I have ever seen. Thanks Dave!

I learned more in this 23 minute video than I did during an entire semester of my semiconductors course in college. Well done!

I've just started studying electrical engineering and I don't get the textbook and I never understand anything on the lectures, so each time i have a test or a laboration I just look at your videos and suddenly I'm the *smartest* one in the room, despite knowing nothing and feeling devastated just hours before. You've literally saved me from failing and even helped me get better grades than I thought was possible. You are the best teacher and I wish the best for you.

Frankly, there is no better lecture on the interent, almost none goes this deep to explain how the elctrons and holes work, after searching for a week to understand it and reading books this one is the best.

Thanks for taking the time to make this video. I have learned something new today and you're responsible for that.

Nice!! These are my favorite videos of yours. You did one similar with op amps. I absolutely love these. They are the reason I subscribe. Thanks so much!

+EEVBlog, that's the best explanation ever, textbook authors should learn how to do this from this one! Massive thumbs-up! Thx!

Thanks a lot Dave for your work and your time! I deeply respect people like you who take their time to spread their knowledge free. Of course, some "Iknoweverythingandimbetterthanyou" people will criticize your work, but what you do is popularization of electronic sciences (and you never claimed it to be anything else, and... no one's perfect). So thank you again! BTW, if i may, you should do also a thursday, wednesday or whatever day lesson, where you present and explain, in a 5 minutes format, week after week, a simple electronic circuit function: example like limiter current system, protection system, etc... but kind of circuit that you build with less than 10 basic components (resistor, transistor, capacitor, diode, even AOP in the most extreme case), not the one that you build round with a specialized IC.

A decent addition to the world's collection of videos explaining how transistors work. Maybe it's just me, but I think the FET is a little easier to understand how it works.

That is a very clear explaination. And the time you needed is not much at all. Had the same stuff at school decades ago but it took the teacher 1.5 full hours to explain. Well done.

Fantastic video, with probably the clearest explanation I have seen so far on this topic. It is something that is actually difficult to teach and you did great!

Best lesson on semi-conductors I've experienced online or in class. Thanks EEVlog!

I love how you specifically distinguish conventional current and electron flow. Fabulous!

This was awesome. Thank you very much! I had that "Ah-Ha!" moment here where it all clicked.

This video should be required viewing in all basic electronic courses. Very well done, Dave.

definitely interested in more vids about how semiconductor devices work! I've been having a little trouble fully grasping how they work, but your detailed descriptions with visual aids definitely clarify things nicely.

I would LOVE to see a nice video about how to drive MOSFETS and BJT, including high currents, and inductive loads with "soft off" AWESOME video!!! Learned a lot! Thanks!

Great videos! Appreciate the level and detail you give when explaining.

Thank you so much! This was very informative and detailed. I loved the Moore’s law explanation at the end.

Easily the clearest explanation of transistors I've seen. Thanks!

Finally someone who speaks clear English and knows what they are talking about.

Really good explanation. I love this channel! A lot of useful stuff. Thank you ,sir !

i made a whole project about bjt's and mosfets in middle school. learned more by watching this video than when i did that project. well done lol

You explained it way better than my Iranian instructor(No Bias), back in the day, Dave. Many thanks!

I've always wanted to know the difference between BJT and Mosfets and this video explains that and even more! Thanks Dave and Keep the great videos coming!

Very good explanation, This is what I have been looking for thanks so much @EEVblog.

Never commented on your videos before but I've been watching this channel for over a year so I thought I'd write one now: EEVblog is full of great insights into electrical engineering, and Fundamentals Friday is my favourite segment. From and inspired by it I have learned a lot of electronics basics. I wish my teachers would've been as inspiring as you are. Maybe I would have gotten into electronics earlier. Electronics for me have turned from a hobby into a job and I'm loving every moment of it. Keep making these videos. You rock! Sincerely, Panu

Awesome video. You explained this better in 20 minutes than my EE professor did in multiple weeks worth of classes. I think university professors need to lay off the math and explain things like this. When they just want to jump into calculations and numbers they fail to explain the greater picture like you do here.

Very good presentation. The only difficult thing was the explanation of the current amplifying physics. That was unclear. The mosfet was very clear.

Awesome dive into into the physical world of transistors!

This is an excellent presentation Dave, well done.

Very well simplified and explained the solid-state-physics things less than 24 min. Well done!

Thank you very much for that wonder explanation. You answered many questions that I was pondering on.

Many thanks for another trip back to basic EE stuff. Actually, a bit of physics as well. Excellent.

Thumbs up Dave, just like the lectures I went through at University.

Mind-boggling I love the way you explain it makes it a little bit easier for someone like me to try and understand many thanks👍

Fantastic video, BJT's really are such wonderful devices

Great video, Dave! Would love to see more educational videos like this.

awesome video! i'm about a month into my circuits 1 course at university and this video is very helpful at helping me understand how transistors work! Hopefully a bit more practice with the calculations and i'll have these things down for the test in 2 weeks.

Absolutely Superb!! Best explanation I've seen. Moreover Australian accent made it just PERFECT!! Thank you mate!!

Thank you so much for this, Dave! I have struggled to understand how transistors really work for years, and you completely cleared it up for me!

Phenomenally good explanation Dave. Thank you so, so much.

Yes, I like fundamentals in Dave's way. Clear as mud : )

This extra electron appearing in doped matrix was brilliantly explained. I've never seen it done graphically, it still makes sens without the picture, but this way it is really easy to understand and remember.

You upload this video just a few days after my exam in the subject!!

Great, Thanks! I'm stil struggling with the BJT, but I guess I'll just look at it again until I get it.

Dave, you are a great instructor, brother!

just by you lightly mentioning the ACTUAL flow of electrons, you have started a great avalanche of debate about this issue. Good stuff.

Thank you very much for the very detailed explanations.

Dave, you are the engineer par excellence, I love fundamental Fridays, I really learned something. thanks you are DA Man!!!

Thank you ...well done.... its helpful and simple to understand .

Excellent Dave!, and a great followup from your last video on why you should learn electronics. Learning a lot and really enjoying it. Tom

Man oh man Couldn't have explained it better My hat is off to you :)

Excellent presentation ! Cheers very much !

I have worked in electronics, both as a career and as a hobby for more than 40 years. Even after reading several articles and books about how transistors work (remember the old RCA transistor manual?), I never really understood it as clearly as your explanation here. Thanks.

You taught me in 20 min what my professor tried to teach me in 2 weeks. Nice Video!

very nice video. I spent hours and hours to try to understand the principle and I felt exhausted and depressed. Your KZfaq can make me understand within a hour.!

Great job Dave.... Exact exactly what I needed!

I have been looking for something like this. Most videos explain at the circuit level but not at the physics level. Thanks.

Dave knows alot of chemistry wow, well elaborated usefull video indeed,kudos!

Yr 12 physics exam on monday, one section is transistors. You couldn't have timed this better

Is anyone else interested in a Fundamental Friday explaining the different physics involved with vacuum tubes compared to transistors?

!!!!!! Thank You !!!!! For Bridging the gap on a 20 year mystery

Perfect, unsurpassed explanation, thank you very much indeed

Outstanding lesson! Thank you Dave!

Dave would make an awesome classroom instructor!

Very good explanation. FETs are new since I studied Physical Electronics in the 60's!

THIS is educational!!! When you break things down to their simplest form and begin rebuilding them until you have a component, the principles of electronics really become evident! Tired issues, like which type of capacitor is "best," become rubbish. Does that cap allow the electron to move from one atom to another? More efficiently than another? I spend WAY to much time listening to the information Dave shares!!! Back to the money square, I go!!!

Hello Dave: I have been watching and learning from many of your videos for the past 10 years and I wanted to take the time out to thank you for the Excellent job of explaining in great detail. I am now retired currently residing as an expatriate with my Philippine born wife in the Philippines. I have 50 years of experience in the field of electronics and electrical almost all phases from power plant, industrial controls, consumer electronics including Tv repair, computer systems and residential and commercial electrical wiring just to mention a few. This experience comes along with vast amount of Technical, Vocational, Military and collegiate education. I would particularly like to mention your video on the TD- 220 Tektronix Digital scope where you were shown reviving one you had found in the mud lol! I happen to have one along with a few others. I decided to pull it out a few days ago for use in troubleshooting a problem to find that the LCD display has gone bad only able to view some traces of letters and figures at high contrast. Well just thought I’d share that with you and let you know you are doing an amazing job. Keep those videos coming.

Thanks Dave, looking forward to more videos like this....total beginner here

This is so fantastic. Thank you, Dave

When I trained with the P.M.G. in the sixties we were taught that the old conventions were wrong, that current flowed from -ve to +ve and that electron flow was the new future in electronics. Easily understood and remembered when you study the operation of a vacuum tube amplifier. At the same time, Cycles per Second (CPS) was being dispensed with and replaced with Hz (in honour of Hertz). Voltage was to be represented by E (for electromotive force) in lieu of V. So, I = E / R. Out with the old and in with the new. Hole movement was theorectical, the electrons moved into the holes leaving holes behind them. In a theatre, there's an empty seat (hole) at the far end of the row. Instead of the new patron (electron) stumbing all the way down the row, it's easier for everyone in the row to move to an adjacent seat. The empty seat (hole) effectively moves to the other end of the row but it's really the patrons (electrons) that are moving. Without a discussion of manufacture and the actual fusing together of the PN layers in an oven, there is no clear understanding here of how the depletion layer forms. These aren't pieces of silicon that are just placed next to each other, they are FUSED. The depletion layer creates an actual potential difference that must be overcome by external forces before current can begin to flow. When and why did the electronics industry revert from the NEW sixties conventions and decide to fall back to confusing ancient conventional current flow and also, bring back "V"?

Very good explanation. I actually understand what is going on now!

this is great, we did this on the physics level today at uni, thanks dave. :)

Great review of stuff I began to learn over 50 years ago as a naive young-ling. But I still love to review it and imagine all of the little particles in there doing my bidding within my amplifiers...

Awesome explanation!!

Hi, Dave, you do a very nice job, thanks a lot!

You made it so easy to understand!

Your work is a treasure, thank you a lot!

This is really useful. Even for people who work with this regularly to be able to explain it to other people. Thanks!

The process of understand is what physics does, but our electronics lecturer teaches only math. Been searching these videos for months. Very good work. Better go into classifications and calculations of V,I, etc in another video.

I've always been confused at the difference between the two, this explains it very well.

Moore's law is nonsense. I put a transistor into my drawer 10 years ago and it did not become smaller at all.

I've finally understood transistors. Thank you

I LOVE! all your videos. Can you do one on how to find total impedance of a parallel RCL circuit im so lost and cant seem to find a good site that explains it.

I loved it! please make more of these, you do an excellent job explaining things! clear, concise, easy to understand! it really helps beginners like me! Although beginner may be a stretch, considering how i see the world in resistive and capacitive values now XD

Congratulations.Thank you for sharing your knowledge with us.Very good English speech,good for non native English speakers .Keep going. Do you plan a video for Depletion type FET transistors?

Great overview! Thank you.

Dave wisely avoided the confusion surrounding the direction of the arrow. Scientists at Bell Labs incorrectly depicted "conventional flow" (plus to minus) when everyone who has ever worked with vacuum tubes knows that electron flow is from minus to plus.

One of your best videos Dave. First thing that comes time mind is you should write books but these videos are far more effective.

If this was taught at my university like this, I would surely be more curious back then when I was younger. We were all about smoking resistors and blowing caps.

Dave, you are a genius. Amazing. Thank you thank you!

Hey Dave love this video! Can you make one on biasing BJTs as well as the different biasing configurations of BJTs?

Just want to point out that the doping on the collector side is light, not heavy. Normally, the doping level is as such: Emitter >> Base > Collector. This is so that when in reverse bias, there won't be a large current flow. If you make a symmetrical BJT, then forward and reverse bias will cause same current flow magnitude.

Nice! Keep them comming! This is digging up my school stuff :-)

Great video, thanks for the thorough but perfectly ELI5'ed explanation! Now I'm really a FULL-stack engineer. :)

Hi Dave, first thanks for all your awesome videos, not only this one. As a small suggestion, the MOSFET it's easier to understand if the 4th terminal (often not shown) is included and conected to the source terminal, so the electric field is applied to the whole substrate creating the conductive channel

Excellent video Dave!! Could you please make a video explaining the manufacturing steps required to produce a transistor/mosfet? For example how do you dope silicon? How are the channels etched? How is the insulating oxide layer created? How are the metal contacts deposited?