EEVblog #748 - How Do Transistors Work?

Dave explains how BJT and MOSFET transistors work at the silicon chip level.
How does a BJT transistor actually amplify current?
P and N type doping, charge carriers, conduction channel, field effect, holes and electrons, all the other good stuff.

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[Afrotechmods]

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

[jeffseward]

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.

[dogastus]

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

[TrentMRobertson]

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

[turtleturtles]

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.

[Homeaudioacademy]

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

[Momentvm]

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

[ESPPsycho]

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!

[julienc.]

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 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.

[jeromepatoux]

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!

[AmadonFaul]

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

[EcocleanPools]

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

[brianbloom]

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.

[Enherj]

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

[Francis-vvkv]

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!

[magicstevethecat]

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

[tostiheld]

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

[azorahai]

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

[thdotaku]

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.

[zacharymccoy]

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