Does the p side of the diode ever "run out" of electrons if the photons keep "pushing' them away and through the n type side presumably eventually to a battery. Or are there just so many electrons that it doesn't matter.
@@TwenOalley if I remember correctly you can say that the electrons from the N material that go into the P material, go out at the conductor. So there's "a new hole" for each electron that go out. Or rather, the amount of holes won't change, they're the hops that electrons can use to move around through the material, thus they determine (along with the free electrons on the N material) the current capacity of the diode. More voltage (pressure) and the diode breaks. From a simplistic point of view.
It's really interesting the implications of all that it's explained on the video. From this an electronics class will go through every (common) type of diode there is (though my class didn't cover solar panels). The depletion zone will always exists, even on a conducting diode. On a conducting silicon diode it will go as high of 0.7v. Imagine having 1 ampere passing through the diode! It will act as a resistance of 0.7 ohm! And that would be 0.7 Watts of energy dissipating on such a small junction!! (now you can kind of understand why LED's need big heat sinks and old lamps don't [heat can dissipate on a bigger area, not just a small junction]) So there's tricks to control and benefit (with drawbacks) those characteristics. Diodes with smaller depletion zones but that "leaks" more current on reverse polarization, diodes that are easier to break their depletion zone on reverse and won't "break" permanently so easily so you can use that voltage as a fixed reference, etc. And the it goes into transistors and all their types! It was a very interesting class.
@@TwenOalley if the diode is not connected electrically there will be depletion to the point where the pressure equalizes. When it is connected as a solar electrical generator it will draw electrons out of the anode if connected to a battery directly, and pack them into the cathode thus charging the battery until the pressure again reaches equilibrium as the anode is depleted and the cathode becomes stuffed. So you could relate the intensity of the light with photon pressure balancing with an opposing electrical pressure within the battery. I have visualized this using 2 water tanks and a centrifugal pump. One water tank is 100 feet higher than the other. Once the water level in the piping going to the higher of the 2 tanks reaches a height equivalent to the maximum head pressure rating of the pump at it's given rpm the water will stop flowing upward and the pump while still turning will be converted from a pump to a heater by virtue of a phenomenon related to fluid shear. Same thing with the solar panel, it gets to a point if it's rated maximum output voltage is less than the rated maximum voltage of the storage media, it stops charging and just creates waste heat. Part of the reason we use an inverter between the generator and the storage.
There's an electric field because the P side has an abundance of positive charge carriers (holes) and the N side has an abundance of negative charge carriers (electrons). This excess of charge in each side causes the electric field to form between the two sides and creates a voltage potential between the two sides. That voltage is about 0.7 volts in silicon diodes, or 0.3 volts in germanium diodes. Which means electrons need at least 0.7v (in silicon) in order to cross the depletion region. Think of it like a hill where you need to give a ball enough energy to roll all the way up.
I feel as if my entire life would have gone down a different path if you'd been the one teaching me physics at school because this was a fantastic video.
Yep! Agreed! I use transistors and diodes but this is the first time someone has managed to explain WHY they work, would love to see an explanation for the transistors but I think I can now guess :)
At 16 I took an entire class in physics+IT cuz was told I would learn how diodes work. End of the year I complained that we never did, and the teacher answered it was impossible without learning loads of complicated stuff first. It took Steve Mould 10 min to explain it.
To really undertand them from an academic perspective you do indeed need a good background in quantum mechanics and math. They don't even get into them until the 2nd or 3rd year of college. But if you're just a hobbyist who's screwing aroun, yeah it doesn't take much. But don't think for a second that they're simple devices. Just look up the Schockley diode equation for a taste. Believe me, Steve didn't come close to fully explaining diodes.
@@VoidHalo But he was told (presumably by a teacher, since he's complained to a teacher afterwards) that they'll have diodes explained to them - it's just false advertising. Nobody expects a 16 year old to understand the "academic perspective" on diodes, but the same way you can understand a piston engine without understanding the Otto cycle (like I do, I've just googled the name) or machine learning without all the calculus behind it. And while I hate to quote people I think "If you can't explain it simply you don't understand it well enough" is appropriate - I think the teacher only knew formal definitions and couldn't (or didn't want to) explain the intuitions.
Naw mate. You've got to learn Quantum Free Electron theory to truly understand. Steve has explained an "incomplete" theory. Yeah Steve can probably explain QFET and Fermi Dirac statistics as well but just pointing out that your teacher was right about a few things
Artaxerxes Do you have any books or links Anything that could explain those I’m currently learning physics on my own Any sources would be helpful for the topics that you have mentioned
I am a high school student from India, this is the best explanation ever on Diodes better than my text books. First time ever commenting on a Veritasium video in 4 years, I think this video is going to sky rocket your channel soon sir. Thank you.
Erixon You’re right, this guy is an amazing teacher. But your arithmetic is scary: Do you really watch a million videos for every comment you write? I’m retired, but even I don’t have that kind of free time.
I wouldn't trust someone who is so inexperienced and a novice at commenting, I'd rather hear from someone who is a professional commenting expert, like Justin Y.
My chemistry lecturer hated anthropomorphising atoms. But in the same module he said we should use the simplest model that explains experimental observations. I think it's a good model!
I can attest that I got taught exactly that in a less intuitive and easy to understand manner in university. Then I said it was bullshit because the lecturer tried to tell us about "holes" without really explaining them...
A lot of university professors are obsessed with being extremely formal all the time, and that alone makes it harder to follow them. One textbook that says "screw that" to all of that is "Introduction To Classical Mechanics" by David Morin. That book is written almost like a kindergarten book, with very casual language and even with limericks thrown in here and there just to ease the mood a bit, and it is _only just_ formal enough to still be acceptable teaching material with correct definitions and proofs etc. And you know what? _That works perfectly fine!_ So that book proves once and for all that all those irritating formalities are completely unnecessary - _it is possible_ to teach science courses without a ton of formalities and stiff language everywhere.
@@Peter_1986 It might make it harder to follow but with these kind of subjects there are asterisks attached to everything. The formality is kind of required to avoid confusion should you go further into depth.
@@ppsarrakis Yes let me teach you all these things. 2 weeks later when you need to do something with what was thought: You remember what you needed to know 2 weeks ago? well forget about that it was wrong, good luck figuring out what was wrong (as no asterisks where given) and looking up what is actually going on. I see nothing wrong with this... (This stuff still happens somewhat with asterisks but at least there is a starting point and you have some idea about what is going on)
After going through my undergrad in physics and never actually understanding semiconductors and diodes, this video has finally let me understand them. As for the whole use of anthropomorphism in your explanation, the way I see it, science communication is often a problem of translation from complicated science language to plain English, and anthropomorphism is one of the simplest ways to bridge that. As long as you provide the context that it's a translation tool, then I don't see what the problem with it is.
Omg this answered so many of my questions I had in school chemistry right now. The topic and video are both very awesome and interesting as well. Keep it up I'm really enjoying your videos ^-^
Exactly I couldn't have said it better...this video makes me haye all my teachers who pretended to be one and just read off everything from the text book...
@@deadheadliving yeah I'm always jealous of the people who had that one teacher that made a difference in their life. The only thing I can remember about my public school teachers is there is one of them that ate paste.
now that your brain is getting better you can stop using bruh,,, also, the value of your car audio should never exceed the blue book value of the car, and put a real muffler back on it, and take off the stupid 3' tall wing, lol
I remember when I was in school (a long time ago now!) and I always seemed to gravitate towards learning from people who were passionate about the subject they were teaching. People who would explain not only what was going on but, usually from their own perspective, why it was interesting. I may not have always agreed that it was interesting but I found their passion for the lesson made me remember the information presented to me. For example, I had a maths teacher who would tell us "just do the sum!" and I didn't pick it up. When I moved class because she was a shit teacher and we did NOT like each other, I was taught the same lesson by a different teacher who explained it, how it could be used and gave a real life example and seemed excited to be explaining it. I learned how to deal with differential equations. If you find your subject interesting/exciting, use that enthusiasm to teach the kids mate. It goes a long way! And keep up the good work. Teachers need more recognition!
Read an essay on how diodes work and found it incredibly fascinating even if it was slightly difficult to understand. I think they did a great job writing the paper and the illustrations were as good as one could make them. I realized before clicking on this video however that a lot of what I read from that essay did not stick. I think after watching this that the info will stick because of your intuitive teaching style and I appreciate that very much. Thank you.
Only after you open the box with schriedingers cat in it, only then you know if the cat loves anthropmorphize. Wjil in the box it both likes and dislikes it at the same time...
This video blew me away in how perfectly it explains how LEDs and Solar panel cells work, and that they are actually the same thing,. Highly recommend this video!
I wont pretend I understood *all* of this on the first go; but you have a great way of explaining and have helped me understand more than I did before! TY and Great work!
Thank you for the introduction to Brilliant as well as the discount. It's just what I needed for my own journey into neural networking and machine learning. Thanks also for your excellent channel. I can appreciate how much effort goes into a single video to have everything that's needed for concise and efficient presentation as a discreet subject without the introduction to tangents. I feel satisfied and complete without a sense of need afterwards. That is a very difficult thing to achieve.
Thanks for the amazing content, as always. I very much respect the simplicity of things when you explain them. I believe that this how science should be taught; intuitively and in simple yet descriptive words. Keep them coming!
I have watched a couple of videos of how diode work but you were the first to make me understand I think representing the holes as a partial really helps
I'm an engineer working in the solar industry. With that in mind, a few of my colleagues would benefit from watching this. Fantastic video, couldn't have explained this in a better way. I'll be stealing some of these explainations when people ask what I do!
The materials I think, that’s probably what the entire industry behind it is about. What materials make efficient and cheap enough mass produced diodes.
Material has a lot to do with it. A silicon diode drops about 0.6 to 0.7v, where a germanium will drop 0.25 to 0.3v or there's a special kind of diode called a schottkey diode where the junction is formed between silicon and a metal which drops as little as 0.2v. This is important, because Ohm's law states that power=voltage x current. So if you have 1 amp of current through a diode, the silicon diode will draw 0.7 watts of power (0.7v x 1A) where te schottkey diode will draw 0.2 watts. This power is just dissipated as heat, so any power drawn by a diode is wasted power. So the less power consumed, the more efficient it is. I hope that helps.
There is also quantum efficiency in LEDs, Photodetectors and Solar Cells which is the fraction of photons to electron-hole pairs generated or LEDs/LASERs the fraction of pair recombinations that actually result in emitted photons. This efficiency does have to do with resistive losses and absorption by the material in areas other than the depletion region. Also Reflection at the surface.
Another factor for lighting is simply many bandgaps are wavelengths (or for our eyes, colors) that we don't directly want, so they will have a phosphor coating to absorb and re-emit at a more pleasant color. Obviously this eats into efficiency.. if I remember correctly, a green LED was sort of elusive so many white lights just had to use blue light with a coating... Although don't quote me on that haha
The few seconds you took to explain that 1. Your knowingly anthropomorphizing 2. That you think it's fine so long as everyone knows it for what it is. Was brilliant and proves to me you are a true scientist.
This is one of the clearest, least intimidating explanations I have seen and I'll be showing it to my first-level electrician students shortly. The only quibble I have is the implication that one takes P-type and N-type material and butts them together. AFAIK, if you literally had two separate pieces of material and attempted to join them together you would never achieve a useful junction. As I understand it, you start with a chunk of silicon and selectively dope different areas of the same piece. Am I upside down on this, or making too much of the distinction for a beginning audience?
A introduction can either be too simple or too detailed. I think this video makes a good first introduction to diodes. And if someone wants some more exact details, then they should look for such additional info. Such as solar panels having multiple layers of semiconductors, to account for different wavelengths.
@@suddeneevee9441 Thanks for your post. I've no problem with any of that, but IMO the concept of selective doping vs. joining separate pieces of doped silicon together doesn't represent a huge leap in the complexity of the concept or its presentation. It would certainly take fewer words than this comment has. 😉
5 лет назад
That is the best explanation of diodes, electrons, holes, depletion zone and LED I've ever seen. Well done sir!
@@wierdalien1 Well, yes and no. There's some incredibly stable organic fluorine compunds, like tetrafuoromethane, or teflon (PTFE) that you mentioned. That would be fluorine in its 'happy' state. And even those compounds usually fuck up the environment and/or people either during their creation, their disposal, or when handled incorrectly. As for 'angry' fluorine... take a look at chlorine trifluoride. Or maybe not. Running away would be smarter. Or better yet: Be somewhere else than that stuff in the first place.
Thank you for the comprehensive yet compact video. If only this video was available in 20 years ago. I spent / wasted 3 years on electrical engineering and digital circuits in university and never fully got my head around this.
Great explanation, as usual. I'm sorry I have to say this :( The shaky-cam effect was cool at first, but then it triggered my vertigo. Sorry! Thanks for sharing this great insight!
Desire to puke rising and only half way through. Excellent video though. Would have loved having this when I was in college. Makes things much easier to understand.
I've been working with semiconductors for 40 years. Yours is the best explanation of the electron/hole and p/n concepts I've ever heard. Lots of fun, thanks!
I'm in second-year university now, and ever since we began to learn about diodes in yr.11 (3+ years ago), I never truly understood how they worked, even after watching video after video. This has made it make sense, thank you so much!
It *can* be made by just pushing p and n type materials together, even though often industrially it is just two halves of the same piece of material doped differently.
After years of exposure to this stuff, this is the first time I've actually understood why one is called P-type and the other is called N-type. Not just that but how putting them together magically gives us diodes and transistors. Bravo.
Actually, rectifying diode or maybe PN junction diode would be better to distinguish regular diodes from the rest. But signal diode is just fine for low power ones which are (obviously) meant for signals. I'm pretty sure a solar cell also uses a PN junction, but the reverse breakdown voltage is so small and the reverse recovery time so long that they would make a terrible rectifier. Zener diodes and avalanche diodes also don't rectify very well either for the same reason. So it seems rectification isn't the sole defining feature of a diode. But at the same time, not all diodes use PN junctions either. Like PIN diodes, which have undoped, or intrinsic semiconductor between P type on one side and N type on the other. Or schottky diodes, which only have a P or N type layer on a metal layer, as in the famous cat's whisker or point contact diode used in foxhole radios. So in terms of what exactly defines a diode, I have no clue. but I aim to find out now that I've realized this. Hope you guys will, too. Cheers.
It has to do with the way diodes break down. In any diode, you still get a very weak reverse current even if the diode is "blocking" because some of the charges are able to cross the depletion zone. Once you approach the breakdown voltage, some of those moving electrons have enough energy to knock electrons that wouldn't normally be free-flowing out of the covalent bonds, and the reverse current sharply rises. This is known as "Impact Ionization" or the "Avalanche Effect". Note that this, in itself, isn't actually damaging to the diode - what damages the diode is the massive current flow and the heat that results from it. Now, a Zener diode has essentially the same construction as a regular diode, but the material is more "heavily" doped. This means that there are more charges in the same volume, and as a result the depletion zone is much thinner. The voltage across it is still the same, though, so the electric field across the depletion zone is much stronger. When you connect a diode in reverse, the electric field across the depletion zone gets stronger, and in the case of a zener diode, strong enough to rip electrons out of the covalent bonds and allow a high current to flow. This is known as the Zener Effect. According to Wikipedia, only zener diodes up to 5.6V actually use this effect, though. Zener diodes for higher voltages supposedly rely simply on the avalanche effect - kind of makes sense, because at that point you're essentially just manufacturing a normal diode. The breakdown voltage is engineered through how heavily doped the material is. It gets a little more interesting, though. Impact ionization is just a matter of raw energy, but the zener effect is actually a quantum tunneling effect. The upshot of that is that low-voltage zener diodes supposedly generate a lot less heat than zener diodes that rely on the avalanche effect.
@@JamecBond And the distance between the top of the LEDs and the rim of the beaker is the energy gap. Jiggle it around (thermal energy) and some will leap out! :)
Very elegantly explained. As a kid, I had an electronics kit that included both a solar cell and an LED. I never new they had anything in common. Now 40 years later, I understand.
I like it when you say, " atoms like to have eight electrons in their outer shell". This is a very good, and great teaching technique. The best teaching method helps one to understanding clearly, and easily. Isn't this the goal for all teachers?
I just took a circuits class in college that essentially was all about diodes and transistors and this video did a far better job at educating me about diodes than that class did. I think I might've understood better having taken that class before, but I definitely better understand diodes now than I did before watching this video. Excellent video.
A someone who studies chemistry and who has known this from a bunch of different sources over a few years, this is exactly what I expected, with no key loss of information, and efficiently simplified.
Man I'm not even halfway through this videos and I'm so happy! THIS is the kind of thing I've always wanted to know about semiconductors and n and p type semiconductors but i have NEVER actually seen it explained properly like this!! THANKS!!!
this is the smoothest explanation ever! like ever! made it not only foreshadow the working of transistor but overall explanation of diodes and those animations are just smooth and easy to understand too
Again, excellent video. You have a natural ability to explain things without over complicating. Had this sort of resource been around during my BTEC, we'd have mastered semiconductor operation in one session rather than having to return to it again and again. And again.
Just watched one of your videos for the first time. It has taken years of looking at many others. In saying that, im several videos in, and you have now become a reference in my onward learning. thank you Steve!
I love your channel. The way you explain how things work it's so well done and you make it much easier to understand. Even my grandmother would understand this. Thanks from Romania Steve.
O.M.G!!!! This is in my opinion the BEST video that I have ever seen explaining WHY a diode works! Thank you for your amazing explanation and use of animation, you're awesome!
I actually paused the video and closed my eyes trying to understand and visualize why the “holes” would be attracted to the negative terminal and I really couldn’t then played the video and he explained it. Good job, you fully comprehend and understand the physics and chemistry or the underlying processes of these topics, rather than just plain “factual” videos most youtubers do which don’t give any arguments or reasons why we should accept those facts.
After failing in Basic Electronics and Electronics & Communication Engineering in college, I understand now that it's not because I was dumb or the subject was too hard, but because having a good teacher can make a world of difference. Thanks a lot :)
Woohoo! Great topic! One interesting note: the moment of the electron is actually different than the hole 'particle'. I sort of forget the implications of this, but I think it affects how solar panel design.. For example, the average distance a 'free' electron travels depends on the odds of it 'colliding' with a hole. If it combines, usually all that happens is that energy makes the atoms wobble (i.e. heat or phonons) which is 'waste' since you want to extract electricity. So the thinner a solar panel is, the more likely you are to catch a free electron (or hole). At the same time, to liberate an electron you need some energy. This can come from heat occasionally but mostly is from a photon (light energy). One thing to note: that band gap Steve mentioned, this is a no-go zone for electrons which must be 'jumped' to transition from being bound to an atom to being a free electron moving through the crystal. So if a photon of light is not energetic enough, it will pass through the material without much interaction (this actually is why glass is transparent to visible light- its bandgap is larger than visible light spectrum. UV light has enough energy, and therefore can be absorbed). On the flip side, if a photon has more energy than the bandgap, the excess energy essentially boosts the electron to a higher energy but the electron quickly drops down to the upper edge of the bandgap, dissipating it as heat (generally speaking). So this limits efficiency: essentially there's frequency of peak efficiency for a given junction. You can stack multiple layers of different materials (higher bandgap on top, since they are transparent to higher wavelengths) which increases efficiency, but is very costly..
I don't know how many explanations I've read/watched/heard (over several years...), but I never really understood why it worked, just that it did somehow... This video finally cleared it all and now it makes sense! Thank you so much!!! BTW: I'm totally fine with you saying atoms want to fill their bonds. ;)
I have been using semiconductors for decades. NOW I have more than just a little clue about what the heck is going on in them. I absolutely loved this video. Thank you so much for making it.
I just learnt in solid states chapter yesterday in my coaching center. Your explanation basically perma cleared the concept of metal excess and deficiency defects for me! Thanks a lot sir!
Very well explained sir! Now I can skip this subject in peace and refer to this video
The electroBOOM seal of approval. That makes me happy!
Hey electro i am a big fan. You make super entertainment videos!
Now you know how a FULL BRIDGE RECTIFIER works
Hey electro boom
I like you channel can you explain transistor
as an electrical engineer, i should say this is the best explanation and animation i've seen.
Thank you
Does the p side of the diode ever "run out" of electrons if the photons keep "pushing' them away and through the n type side presumably eventually to a battery. Or are there just so many electrons that it doesn't matter.
@@TwenOalley if I remember correctly you can say that the electrons from the N material that go into the P material, go out at the conductor. So there's "a new hole" for each electron that go out.
Or rather, the amount of holes won't change, they're the hops that electrons can use to move around through the material, thus they determine (along with the free electrons on the N material) the current capacity of the diode. More voltage (pressure) and the diode breaks.
From a simplistic point of view.
It's really interesting the implications of all that it's explained on the video. From this an electronics class will go through every (common) type of diode there is (though my class didn't cover solar panels).
The depletion zone will always exists, even on a conducting diode. On a conducting silicon diode it will go as high of 0.7v. Imagine having 1 ampere passing through the diode! It will act as a resistance of 0.7 ohm! And that would be 0.7 Watts of energy dissipating on such a small junction!! (now you can kind of understand why LED's need big heat sinks and old lamps don't [heat can dissipate on a bigger area, not just a small junction])
So there's tricks to control and benefit (with drawbacks) those characteristics. Diodes with smaller depletion zones but that "leaks" more current on reverse polarization, diodes that are easier to break their depletion zone on reverse and won't "break" permanently so easily so you can use that voltage as a fixed reference, etc.
And the it goes into transistors and all their types! It was a very interesting class.
@@TwenOalley yes, it's possible
@@TwenOalley if the diode is not connected electrically there will be depletion to the point where the pressure equalizes.
When it is connected as a solar electrical generator it will draw electrons out of the anode if connected to a battery directly, and pack them into the cathode thus charging the battery until the pressure again reaches equilibrium as the anode is depleted and the cathode becomes stuffed. So you could relate the intensity of the light with photon pressure balancing with an opposing electrical pressure within the battery.
I have visualized this using 2 water tanks and a centrifugal pump. One water tank is 100 feet higher than the other. Once the water level in the piping going to the higher of the 2 tanks reaches a height equivalent to the maximum head pressure rating of the pump at it's given rpm the water will stop flowing upward and the pump while still turning will be converted from a pump to a heater by virtue of a phenomenon related to fluid shear. Same thing with the solar panel, it gets to a point if it's rated maximum output voltage is less than the rated maximum voltage of the storage media, it stops charging and just creates waste heat. Part of the reason we use an inverter between the generator and the storage.
As a grad student in physics, probably the most easy to understand explanation of this I've seen.
Bertus van Heerden
We take this stuff in high school
It amazes me how well he explained it
Do you know why there is a resultant electric field @8:38 then?
There's an electric field because the P side has an abundance of positive charge carriers (holes) and the N side has an abundance of negative charge carriers (electrons). This excess of charge in each side causes the electric field to form between the two sides and creates a voltage potential between the two sides. That voltage is about 0.7 volts in silicon diodes, or 0.3 volts in germanium diodes. Which means electrons need at least 0.7v (in silicon) in order to cross the depletion region. Think of it like a hill where you need to give a ball enough energy to roll all the way up.
But did you finally understand it?
As someone who knows nothing about this subject I would say the same!
I feel as if my entire life would have gone down a different path if you'd been the one teaching me physics at school because this was a fantastic video.
Brassica more like bra stuffing Jessica
Same
@@AndrewStinton Solidarity, friend 😑
So now is easier to understand transistors. Can you make a video about PNP and NPN transistors? would be awesome!
I second this!!
No,that would be useful
seconding
Yep! Agreed! I use transistors and diodes but this is the first time someone has managed to explain WHY they work, would love to see an explanation for the transistors but I think I can now guess :)
That would be great 👍🏻
At 16 I took an entire class in physics+IT cuz was told I would learn how diodes work. End of the year I complained that we never did, and the teacher answered it was impossible without learning loads of complicated stuff first.
It took Steve Mould 10 min to explain it.
To really undertand them from an academic perspective you do indeed need a good background in quantum mechanics and math. They don't even get into them until the 2nd or 3rd year of college. But if you're just a hobbyist who's screwing aroun, yeah it doesn't take much. But don't think for a second that they're simple devices. Just look up the Schockley diode equation for a taste. Believe me, Steve didn't come close to fully explaining diodes.
@@VoidHalo But he was told (presumably by a teacher, since he's complained to a teacher afterwards) that they'll have diodes explained to them - it's just false advertising. Nobody expects a 16 year old to understand the "academic perspective" on diodes, but the same way you can understand a piston engine without understanding the Otto cycle (like I do, I've just googled the name) or machine learning without all the calculus behind it.
And while I hate to quote people I think "If you can't explain it simply you don't understand it well enough" is appropriate - I think the teacher only knew formal definitions and couldn't (or didn't want to) explain the intuitions.
There's no replacing a persistent yet patient teacher, animation helps though
Naw mate. You've got to learn Quantum Free Electron theory to truly understand. Steve has explained an "incomplete" theory. Yeah Steve can probably explain QFET and Fermi Dirac statistics as well but just pointing out that your teacher was right about a few things
Artaxerxes
Do you have any books or links
Anything that could explain those
I’m currently learning physics on my own
Any sources would be helpful for the topics that you have mentioned
I am a high school student from India, this is the best explanation ever on Diodes better than my text books. First time ever commenting on a Veritasium video in 4 years, I think this video is going to sky rocket your channel soon sir. Thank you.
This has to be the best explanation of diode in my opinion.
I comment on 0.000001% of the vids that I watch. This guy is the best teacher I have ever encountered.
Erixon You’re right, this guy is an amazing teacher. But your arithmetic is scary: Do you really watch a million videos for every comment you write? I’m retired, but even I don’t have that kind of free time.
I wouldn't trust someone who is so inexperienced and a novice at commenting, I'd rather hear from someone who is a professional commenting expert, like Justin Y.
Maybe he isn't gonna say that on a video for his entire life
@@smartypants1588 smarty pants trying to be a smart ass
I am an electronics engineer and I think it can not be explained any better. Well done. ;)
My chemistry lecturer hated anthropomorphising atoms. But in the same module he said we should use the simplest model that explains experimental observations. I think it's a good model!
Your chemistry lecturer maybe wasn't aware that he is atoms. :P
This explanation makes me wish RUclips had a love button.
I can attest that I got taught exactly that in a less intuitive and easy to understand manner in university. Then I said it was bullshit because the lecturer tried to tell us about "holes" without really explaining them...
Same! University lecturers often do not have a teaching qualification, only expertise in their field. BOTH are required.
A lot of university professors are obsessed with being extremely formal all the time, and that alone makes it harder to follow them.
One textbook that says "screw that" to all of that is "Introduction To Classical Mechanics" by David Morin.
That book is written almost like a kindergarten book, with very casual language and even with limericks thrown in here and there just to ease the mood a bit, and it is _only just_ formal enough to still be acceptable teaching material with correct definitions and proofs etc.
And you know what?
_That works perfectly fine!_
So that book proves once and for all that all those irritating formalities are completely unnecessary - _it is possible_ to teach science courses without a ton of formalities and stiff language everywhere.
@@Peter_1986 It might make it harder to follow but with these kind of subjects there are asterisks attached to everything. The formality is kind of required to avoid confusion should you go further into depth.
@@someonespotatohmm9513 exactly,you are supposed to do further study/research to understand stuff...
@@ppsarrakis Yes let me teach you all these things.
2 weeks later when you need to do something with what was thought: You remember what you needed to know 2 weeks ago? well forget about that it was wrong, good luck figuring out what was wrong (as no asterisks where given) and looking up what is actually going on.
I see nothing wrong with this... (This stuff still happens somewhat with asterisks but at least there is a starting point and you have some idea about what is going on)
After going through my undergrad in physics and never actually understanding semiconductors and diodes, this video has finally let me understand them.
As for the whole use of anthropomorphism in your explanation, the way I see it, science communication is often a problem of translation from complicated science language to plain English, and anthropomorphism is one of the simplest ways to bridge that. As long as you provide the context that it's a translation tool, then I don't see what the problem with it is.
as a student studying electrical engineering this is super helpful, Thanks!
Omg this answered so many of my questions I had in school chemistry right now. The topic and video are both very awesome and interesting as well. Keep it up I'm really enjoying your videos ^-^
Paradox _tenses,_ much? 👀
Been waiting for this explanation!
+
@@sillyshitt
The graphics in this video are INCREDIBLE. I FINALLY understand diodes. Thank you!
This is how teachers picture themselves teaching.
Exactly I couldn't have said it better...this video makes me haye all my teachers who pretended to be one and just read off everything from the text book...
@@deadheadliving yeah I'm always jealous of the people who had that one teacher that made a difference in their life. The only thing I can remember about my public school teachers is there is one of them that ate paste.
Yeah but it's not always the case😂😂🤭
I respect good teachers
This has been the best explanation of how diodes work I stumbled accross in decades. Good job, sir.
Wow, this dude is really good at explaining shit. I actually understood all that. My brain now has a few more wrinkles, thanks bruh
B R U H
The smooth brains have lost another one :(
now that your brain is getting better you can stop using bruh,,, also, the value of your car audio should never exceed the blue book value of the car, and put a real muffler back on it, and take off the stupid 3' tall wing, lol
and please pull up those pants, we don't need to see your underwear
@@jakeqwaninne8502 I'm 52 Jake, I was using Bruh just to be silly. Love how you judge someone on the use of a word tho, thats so cool of you
Wow! Amazing.
Im a teacher and im always glad to bring those kind of stuff into class.
I remember when I was in school (a long time ago now!) and I always seemed to gravitate towards learning from people who were passionate about the subject they were teaching. People who would explain not only what was going on but, usually from their own perspective, why it was interesting. I may not have always agreed that it was interesting but I found their passion for the lesson made me remember the information presented to me. For example, I had a maths teacher who would tell us "just do the sum!" and I didn't pick it up. When I moved class because she was a shit teacher and we did NOT like each other, I was taught the same lesson by a different teacher who explained it, how it could be used and gave a real life example and seemed excited to be explaining it. I learned how to deal with differential equations.
If you find your subject interesting/exciting, use that enthusiasm to teach the kids mate. It goes a long way! And keep up the good work. Teachers need more recognition!
This is so far the best animated video explaining PN junction. The second best one was a 3d video with a skateboard analogy that is many years old.
Ikr
Not only your explanation is the best I've ever heard, but also I find your english very clear to me, a no native speaker.
The best explanation I've heard so far 👍
What I love is that you take you time, not like other channels, rushing trough special relativity in 2 minutes. Well done.
That solar panel part kinda blew my mind.
Read an essay on how diodes work and found it incredibly fascinating even if it was slightly difficult to understand. I think they did a great job writing the paper and the illustrations were as good as one could make them. I realized before clicking on this video however that a lot of what I read from that essay did not stick. I think after watching this that the info will stick because of your intuitive teaching style and I appreciate that very much. Thank you.
My cat loves when I anthropomorphize things.
Hol' up
This is hilarious and I don't know what the term for what you just did is!
What is it!?!
@@Ratchet4647 I don't know but it reminds me of the "Self-Demonstrating Article" article on TV Tropes.
So does your chair.
Only after you open the box with schriedingers cat in it, only then you know if the cat loves anthropmorphize. Wjil in the box it both likes and dislikes it at the same time...
This is the best explanation I've seen of diodes, P-type and N-type gaps. Thanks!
Wow, you could have not said it in a simpler
Your explanation is on point.
This video blew me away in how perfectly it explains how LEDs and Solar panel cells work, and that they are actually the same thing,. Highly recommend this video!
I feel like youve been wanting to do that rant for a while
I wont pretend I understood *all* of this on the first go; but you have a great way of explaining and have helped me understand more than I did before! TY and Great work!
Thanks a lot sir ❤
you are such a great person and your channel is very useful ❤
Thank you for the introduction to Brilliant as well as the discount. It's just what I needed for my own journey into neural networking and machine learning. Thanks also for your excellent channel. I can appreciate how much effort goes into a single video to have everything that's needed for concise and efficient presentation as a discreet subject without the introduction to tangents. I feel satisfied and complete without a sense of need afterwards. That is a very difficult thing to achieve.
Thank you. That's basically what I'm aiming for. So it's really to to hear that I'm achieving that for some people.
I graduated electronics engineering but this made everything clearer about diodes. Nice!
Probably the best explanation of the physics of semiconductor diodes I've ever seen.
Thanks for the amazing content, as always. I very much respect the simplicity of things when you explain them. I believe that this how science should be taught; intuitively and in simple yet descriptive words. Keep them coming!
I have watched a couple of videos of how diode work but you were the first to make me understand I think representing the holes as a partial really helps
This would've been such a useful resource in my semiconductors course
What a great teacher. I like his channel because he takes complicated ideas and deconstructs them to simple explanations. So much respect
After literally 10 hours, i finally came across this video. Thank God, now I might not fail physics :D
I'm an engineer working in the solar industry. With that in mind, a few of my colleagues would benefit from watching this. Fantastic video, couldn't have explained this in a better way. I'll be stealing some of these explainations when people ask what I do!
Very interesting! So what determines how 'efficient' these diodes are?
The materials I think, that’s probably what the entire industry behind it is about. What materials make efficient and cheap enough mass produced diodes.
Material has a lot to do with it. A silicon diode drops about 0.6 to 0.7v, where a germanium will drop 0.25 to 0.3v or there's a special kind of diode called a schottkey diode where the junction is formed between silicon and a metal which drops as little as 0.2v. This is important, because Ohm's law states that power=voltage x current. So if you have 1 amp of current through a diode, the silicon diode will draw 0.7 watts of power (0.7v x 1A) where te schottkey diode will draw 0.2 watts. This power is just dissipated as heat, so any power drawn by a diode is wasted power. So the less power consumed, the more efficient it is. I hope that helps.
There is also quantum efficiency in LEDs, Photodetectors and Solar Cells which is the fraction of photons to electron-hole pairs generated or LEDs/LASERs the fraction of pair recombinations that actually result in emitted photons.
This efficiency does have to do with resistive losses and absorption by the material in areas other than the depletion region. Also Reflection at the surface.
Another factor for lighting is simply many bandgaps are wavelengths (or for our eyes, colors) that we don't directly want, so they will have a phosphor coating to absorb and re-emit at a more pleasant color. Obviously this eats into efficiency.. if I remember correctly, a green LED was sort of elusive so many white lights just had to use blue light with a coating... Although don't quote me on that haha
Tests.
The few seconds you took to explain that 1. Your knowingly anthropomorphizing
2. That you think it's fine so long as everyone knows it for what it is.
Was brilliant and proves to me you are a true scientist.
This is one of the clearest, least intimidating explanations I have seen and I'll be showing it to my first-level electrician students shortly. The only quibble I have is the implication that one takes P-type and N-type material and butts them together. AFAIK, if you literally had two separate pieces of material and attempted to join them together you would never achieve a useful junction. As I understand it, you start with a chunk of silicon and selectively dope different areas of the same piece. Am I upside down on this, or making too much of the distinction for a beginning audience?
A introduction can either be too simple or too detailed. I think this video makes a good first introduction to diodes.
And if someone wants some more exact details, then they should look for such additional info. Such as solar panels having multiple layers of semiconductors, to account for different wavelengths.
@@suddeneevee9441 Thanks for your post. I've no problem with any of that, but IMO the concept of selective doping vs. joining separate pieces of doped silicon together doesn't represent a huge leap in the complexity of the concept or its presentation. It would certainly take fewer words than this comment has. 😉
That is the best explanation of diodes, electrons, holes, depletion zone and LED I've ever seen. Well done sir!
Fluorine likes to do horrible things to its surroundings even when it's in its 'happy' state, so making it 'angry' is not really a smart thing to do.
Unless its teflon
@@wierdalien1 Well, yes and no. There's some incredibly stable organic fluorine compunds, like tetrafuoromethane, or teflon (PTFE) that you mentioned. That would be fluorine in its 'happy' state. And even those compounds usually fuck up the environment and/or people either during their creation, their disposal, or when handled incorrectly.
As for 'angry' fluorine... take a look at chlorine trifluoride. Or maybe not. Running away would be smarter. Or better yet: Be somewhere else than that stuff in the first place.
I love the way you anthropomorphize atoms, NaHCO3
@@nahco3994 well yeah creation of PTFE requires straight flourine
What do you mean, floorine is what the floor is made of, what else am i supposed to walk on?
Thank you for the comprehensive yet compact video.
If only this video was available in 20 years ago. I spent / wasted 3 years on electrical engineering and digital circuits in university and never fully got my head around this.
Great explanation, as usual. I'm sorry I have to say this :( The shaky-cam effect was cool at first, but then it triggered my vertigo. Sorry! Thanks for sharing this great insight!
This is useful feedback thank you.
Desire to puke rising and only half way through. Excellent video though. Would have loved having this when I was in college. Makes things much easier to understand.
Agreed!
Omg. I was just looking in the comments because I was feeling weird from the shaky videos. I felt dizzy. Didn't know it could be slight vertigo.
I've been working with semiconductors for 40 years. Yours is the best explanation of the electron/hole and p/n concepts I've ever heard. Lots of fun, thanks!
Does a solar diode then also work best from infrared light, or do the visible light photons work just as well?
have a read: www.sciencedirect.com/science/article/pii/S0927024805002345
Or: Depends on the material your "solar diode" is made of.
@@zn4rf this is not free?
I'm in second-year university now, and ever since we began to learn about diodes in yr.11 (3+ years ago), I never truly understood how they worked, even after watching video after video.
This has made it make sense, thank you so much!
Minor correction. The pn junction isn't made by pushing two materials together
This isn't really a correction, just pointing out a potential incorrect statement.
This video is simplified, semiconductor manufacturing is another story.
It *can* be made by just pushing p and n type materials together, even though often industrially it is just two halves of the same piece of material doped differently.
After years of exposure to this stuff, this is the first time I've actually understood why one is called P-type and the other is called N-type. Not just that but how putting them together magically gives us diodes and transistors. Bravo.
61 people disliked because they are NEGATIVE. Hopefully they decide to reverse polarity and leave a like :D
I understood diode and led with your video after years. Very simplified and professional. Keep the good work man.
"Diodes, LEDs and solar panels" --> So diodes, diodes and diodes?
All are diodes, but the first "diodes" you mention are usually called "signal diodes" because of their application.
Actually, rectifying diode or maybe PN junction diode would be better to distinguish regular diodes from the rest. But signal diode is just fine for low power ones which are (obviously) meant for signals. I'm pretty sure a solar cell also uses a PN junction, but the reverse breakdown voltage is so small and the reverse recovery time so long that they would make a terrible rectifier. Zener diodes and avalanche diodes also don't rectify very well either for the same reason.
So it seems rectification isn't the sole defining feature of a diode. But at the same time, not all diodes use PN junctions either. Like PIN diodes, which have undoped, or intrinsic semiconductor between P type on one side and N type on the other.
Or schottky diodes, which only have a P or N type layer on a metal layer, as in the famous cat's whisker or point contact diode used in foxhole radios.
So in terms of what exactly defines a diode, I have no clue. but I aim to find out now that I've realized this. Hope you guys will, too. Cheers.
Fries, Chips and Mashed Potatoes
This was explained at the Oxford uni materials science open day, but i could only follow your explanation. Really appreciate your videos
Never gonna look at my TV the same again.
Probably the best teacher I've ever seen. THANK YOU
Ok, so what's the deal with zener diodes?
It has to do with the way diodes break down. In any diode, you still get a very weak reverse current even if the diode is "blocking" because some of the charges are able to cross the depletion zone. Once you approach the breakdown voltage, some of those moving electrons have enough energy to knock electrons that wouldn't normally be free-flowing out of the covalent bonds, and the reverse current sharply rises. This is known as "Impact Ionization" or the "Avalanche Effect". Note that this, in itself, isn't actually damaging to the diode - what damages the diode is the massive current flow and the heat that results from it.
Now, a Zener diode has essentially the same construction as a regular diode, but the material is more "heavily" doped. This means that there are more charges in the same volume, and as a result the depletion zone is much thinner. The voltage across it is still the same, though, so the electric field across the depletion zone is much stronger. When you connect a diode in reverse, the electric field across the depletion zone gets stronger, and in the case of a zener diode, strong enough to rip electrons out of the covalent bonds and allow a high current to flow. This is known as the Zener Effect.
According to Wikipedia, only zener diodes up to 5.6V actually use this effect, though. Zener diodes for higher voltages supposedly rely simply on the avalanche effect - kind of makes sense, because at that point you're essentially just manufacturing a normal diode. The breakdown voltage is engineered through how heavily doped the material is.
It gets a little more interesting, though. Impact ionization is just a matter of raw energy, but the zener effect is actually a quantum tunneling effect. The upshot of that is that low-voltage zener diodes supposedly generate a lot less heat than zener diodes that rely on the avalanche effect.
As an electronic technician, I consider this by far the best explanation I've seen on the subject.
0/10, nothing poured out of a beaker.
@@JamecBond And the distance between the top of the LEDs and the rim of the beaker is the energy gap. Jiggle it around (thermal energy) and some will leap out! :)
this guy explained in 12 mins what i "tried" to learn in 3 semesters. well done mate
theoretically .. an amoled phone could charge itself when you lay it screen up in the sun ;)
Why has no-one commented on this, even just in banal admiration of the sentiment? We need naturally solar-powered AMOLED phones!
I don't think it's optimized for that. The charging rate would be slower than depletion rate.
But it would be cool if it was optimized for that :)
Very elegantly explained. As a kid, I had an electronics kit that included both a solar cell and an LED. I never new they had anything in common. Now 40 years later, I understand.
When you were talking about anthropomorphising atoms, the first thing I thought of was 'catoms'. catgirl-atoms.
Someone, please draw this xD
You mean Ions? Cations?
this channel is so unique , and it isn't just entertaining it actually makes you more knowledgeable
Is Ali D related to Ali G ?
Yeah, they're both Ali A's brothers
I like it when you say, " atoms like to have eight electrons in their outer shell". This is a very good, and great teaching technique. The best teaching method helps one to understanding clearly, and easily. Isn't this the goal for all teachers?
I just took a circuits class in college that essentially was all about diodes and transistors and this video did a far better job at educating me about diodes than that class did. I think I might've understood better having taken that class before, but I definitely better understand diodes now than I did before watching this video. Excellent video.
I love your presentation style and voice. It's soothing yet engaged, a rare combination on RUclips.
35 years after engineering school, this is the BEST explanation of diodes I've ever read & heard.
A someone who studies chemistry and who has known this from a bunch of different sources over a few years, this is exactly what I expected, with no key loss of information, and efficiently simplified.
Man I'm not even halfway through this videos and I'm so happy! THIS is the kind of thing I've always wanted to know about semiconductors and n and p type semiconductors but i have NEVER actually seen it explained properly like this!! THANKS!!!
this is the smoothest explanation ever! like ever! made it not only foreshadow the working of transistor but overall explanation of diodes and those animations are just smooth and easy to understand too
As a predominantly visual learner, I really appreciate your video and the previous one. Thanks.
Again, excellent video. You have a natural ability to explain things without over complicating. Had this sort of resource been around during my BTEC, we'd have mastered semiconductor operation in one session rather than having to return to it again and again.
And again.
I honestly understand solar panels way better from this video than from lectures at university, thank you Steve Mould for this video!
I had this explained to me 4 times during my BSEE and MSEE courses, and this video is the best explanation I've ever seen!
This is the best explnation of diods currently available on RUclips.
Thanks to Steve 👍👍
Just watched one of your videos for the first time. It has taken years of looking at many others. In saying that, im several videos in, and you have now become a reference in my onward learning. thank you Steve!
I love your channel. The way you explain how things work it's so well done and you make it much easier to understand. Even my grandmother would understand this. Thanks from Romania Steve.
Can you make a video and explain quantum phisics? With your own words
I wish my university lecturers were teaching like you. Such a great explanation!
Excellent tutorial, not scarifying the basic physics and make it very understandable.
O.M.G!!!! This is in my opinion the BEST video that I have ever seen explaining WHY a diode works! Thank you for your amazing explanation and use of animation, you're awesome!
I actually paused the video and closed my eyes trying to understand and visualize why the “holes” would be attracted to the negative terminal and I really couldn’t then played the video and he explained it. Good job, you fully comprehend and understand the physics and chemistry or the underlying processes of these topics, rather than just plain “factual” videos most youtubers do which don’t give any arguments or reasons why we should accept those facts.
After failing in Basic Electronics and Electronics & Communication Engineering in college, I understand now that it's not because I was dumb or the subject was too hard, but because having a good teacher can make a world of difference. Thanks a lot :)
Woohoo! Great topic! One interesting note: the moment of the electron is actually different than the hole 'particle'. I sort of forget the implications of this, but I think it affects how solar panel design..
For example, the average distance a 'free' electron travels depends on the odds of it 'colliding' with a hole. If it combines, usually all that happens is that energy makes the atoms wobble (i.e. heat or phonons) which is 'waste' since you want to extract electricity. So the thinner a solar panel is, the more likely you are to catch a free electron (or hole). At the same time, to liberate an electron you need some energy. This can come from heat occasionally but mostly is from a photon (light energy). One thing to note: that band gap Steve mentioned, this is a no-go zone for electrons which must be 'jumped' to transition from being bound to an atom to being a free electron moving through the crystal. So if a photon of light is not energetic enough, it will pass through the material without much interaction (this actually is why glass is transparent to visible light- its bandgap is larger than visible light spectrum. UV light has enough energy, and therefore can be absorbed). On the flip side, if a photon has more energy than the bandgap, the excess energy essentially boosts the electron to a higher energy but the electron quickly drops down to the upper edge of the bandgap, dissipating it as heat (generally speaking). So this limits efficiency: essentially there's frequency of peak efficiency for a given junction. You can stack multiple layers of different materials (higher bandgap on top, since they are transparent to higher wavelengths) which increases efficiency, but is very costly..
The world needs more people like you.
I don't know how many explanations I've read/watched/heard (over several years...), but I never really understood why it worked, just that it did somehow... This video finally cleared it all and now it makes sense! Thank you so much!!!
BTW: I'm totally fine with you saying atoms want to fill their bonds. ;)
Best explanation so far
I have been using semiconductors for decades. NOW I have more than just a little clue about what the heck is going on in them. I absolutely loved this video. Thank you so much for making it.
This respected man is an authority on the subject; a master!
I never understood any of this and always wanted to. I cannot thank you enough for this moment of clarity.
you've explained in 12 minutes what ive studied for as many hours from college lecture videos, and done a better job.
kudos
This is by far the best explanation I've seen for this topic
I just learnt in solid states chapter yesterday in my coaching center. Your explanation basically perma cleared the concept of metal excess and deficiency defects for me! Thanks a lot sir!