How diodes, LEDs and solar panels work

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It looks like I may have been a little off on the explanation. Specifically attributing the movement of charge carriers exclusively to the electric field that build up. Read more about that here:
www.quora.com/How-do-solar-ce...
Animations by Dom Burgess. His brilliant channel, Every Think, is here:
/ @domburgess
Part 1 demonstration video is here: • Why all solar panels a...
Photovoltaic cells and LEDs are both made of diodes. Diodes are designed to allow electricity to flow in one direction only but the way we make them (out of semiconductors) means that can absorb and emit light.
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[@ElectroBOOM]

Very well explained sir! Now I can skip this subject in peace and refer to this video

[@SteveMould]

The electroBOOM seal of approval. That makes me happy!

[@rosen4940]

Hey electro i am a big fan. You make super entertainment videos!

[@Simon8162]

Now you know how a FULL BRIDGE RECTIFIER works

[@lightningmcqueen1577]

Hey electro boom

[@shamimsk4738]

I like you channel can you explain transistor

[@bertusvanheerden]

As a grad student in physics, probably the most easy to understand explanation of this I've seen.

[@XxPlayMakerxX131]

Bertus van Heerden We take this stuff in high school It amazes me how well he explained it

[@ayhamsaffar8407]

Do you know why there is a resultant electric field @8:38 then?

[@halonothing1]

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.

[@31redorange08]

But did you finally understand it?

[@MrEDMeaner]

As someone who knows nothing about this subject I would say the same!

[@gigglysamentz2021]

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.

[@halonothing1]

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.

[@wojtek4p4]

​@@halonothing1 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.

[@jasond.healerlynch5255]

There's no replacing a persistent yet patient teacher, animation helps though

[@Artaxerxes.]

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

[@XxPlayMakerxX131]

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

[@colunizator]

as an electrical engineer, i should say this is the best explanation and animation i've seen. Thank you

[@TwenOalley]

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.

[@sdlion7287]

​@@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.

[@sdlion7287]

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.

[@ericl8743]

@@TwenOalley yes, it's possible

[@3dw3dw]

@@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.

[@Brockohliflower]

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.

[@lawliet2263]

Brassica more like bra stuffing Jessica

[@AndrewStinton]

Same

[@Brockohliflower]

@@AndrewStinton Solidarity, friend 😑

[@guilhemedemassenaladario]

So now is easier to understand transistors. Can you make a video about PNP and NPN transistors? would be awesome!

[@diatribeeverything]

I second this!!

[@glenbaker5311]

No,that would be useful

[@stulora3172]

seconding

[@musicforlife4571]

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 :)

[@mohammadalnahari6531]

That would be great 👍🏻

[@rahulpujari14507]

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.

[@hahahurfunnyno]

I comment on 0.000001% of the vids that I watch. This guy is the best teacher I have ever encountered.

[@smartypants1588]

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.

[@the_original_Bilb_Ono]

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.

[@diamondknyfe3900]

Maybe he isn't gonna say that on a video for his entire life

[@lawliet2263]

@@smartypants1588 smarty pants trying to be a smart ass

[@rocketdogticker]

This is how teachers picture themselves teaching.

[@deadheadliving]

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...

[@rocketdogticker]

@@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.

[@mapalojohnchanda4107]

Yeah but it's not always the case😂😂🤭

[@naman4067]

I respect good teachers

[@TheSam1902]

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...

[@YouKnowMeFromSchool]

Same! University lecturers often do not have a teaching qualification, only expertise in their field. BOTH are required.

[@Peter_1986]

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.

[@someonespotatohmm9513]

@@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]

@@someonespotatohmm9513 exactly,you are supposed to do further study/research to understand stuff...

[@someonespotatohmm9513]

@@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)

[@gigglysamentz2021]

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!

[@thewiseturtle]

Your chemistry lecturer maybe wasn't aware that he is atoms. :P

[@michaelvendick2785]

Wow, this dude is really good at explaining shit. I actually understood all that. My brain now has a few more wrinkles, thanks bruh

[@ifarded630]

B R U H

[@skie6282]

The smooth brains have lost another one :(

[@jakeqwaninne8502]

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

[@jakeqwaninne8502]

and please pull up those pants, we don't need to see your underwear

[@michaelvendick2785]

@@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

[@ChrisWCorp]

My cat loves when I anthropomorphize things.

[@JayJay64100]

Hol' up

[@Ratchet4647]

This is hilarious and I don't know what the term for what you just did is! What is it!?!

[@rozaepareza]

@@Ratchet4647 I don't know but it reminds me of the "Self-Demonstrating Article" article on TV Tropes.

[@Nic7320]

So does your chair.

[@airgliderz]

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...

[@alphaomega95]

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.

[@fatihkaraken2897]

I am an electronics engineer and I think it can not be explained any better. Well done. ;)

[@jacobmarciniec]

This explanation makes me wish KZbin had a love button.

[@danielbloom8540]

as a student studying electrical engineering this is super helpful, Thanks!

[@felixr6600]

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 ^-^

[@lazertroll702]

Paradox _tenses,_ much? 👀

[@chrisengland5523]

Probably the best explanation of the physics of semiconductor diodes I've ever seen.

[@-Rahad]

This has to be the best explanation of diode in my opinion.

[@kikivoorburg]

Been waiting for this explanation!

[@sillyshitt]

+

[@fizzywizzylemonsqueezy1774]

@@sillyshitt

[@leozendo3500]

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.

[@XxPlayMakerxX131]

Ikr

[@ettoregalli72]

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.

[@LEDewey_MD]

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!

[@tachzusamm]

This has been the best explanation of how diodes work I stumbled accross in decades. Good job, sir.

[@yohaijohn]

Wow! Amazing. Im a teacher and im always glad to bring those kind of stuff into class.

[@MrBaldypete1]

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!

That is the best explanation of diodes, electrons, holes, depletion zone and LED I've ever seen. Well done sir!

[@halonothing1]

You actually can't just push an N type and P type crystal together to create a PN junction diode. The boundary between the crystals prevents the depletion later from forming. The P and N type layers need to be formed within the same crystal so N type charge carriers can diffuse over to the P side and vice versa, to form the depletion layer in the PN junction. This is why you can't make a transistor by putting 2 PN diodes back to back in a circuit. Even though a transistor is just 2 PN junctions back to back, it has to be in the same crystal. Other than that small issue, I thought the rest of this was spot on and well presented. I always love watching your videos, especially about electronics because that's my passion. Cheers.

[@XxPlayMakerxX131]

Wow, you could have not said it in a simpler Your explanation is on point.

[@PoohStickProductions]

That solar panel part kinda blew my mind.

[@AirsoftAbominations]

Guys a tolerable, less smug smarter every day, actually good at explaining and doesn't just use long words for the hell of it

[@lewismassie]

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.

[@matejzatko2085]

The best explanation I've heard so far 👍

[@wierdalien1]

I feel like youve been wanting to do that rant for a while

[@kennethbransford820]

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?

[@mariaelisa1164]

Probably the best teacher I've ever seen. THANK YOU

[@moazelsawaf2000]

Thanks a lot sir ❤ you are such a great person and your channel is very useful ❤

[@fahdal-sebaey3322]

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!

[@coolkidnyc]

this guy explained in 12 mins what i "tried" to learn in 3 semesters. well done mate

[@ToddGallant]

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.

[@nahco3994]

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.

[@wierdalien1]

Unless its teflon

[@nahco3994]

@@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.

[@OrangeC7]

​I love the way you anthropomorphize atoms, NaHCO3

[@wierdalien1]

@@nahco3994 well yeah creation of PTFE requires straight flourine

[@jay-tbl]

What do you mean, floorine is what the floor is made of, what else am i supposed to walk on?

[@Lewini]

This would've been such a useful resource in my semiconductors course

[@senorpoodles1755]

The graphics in this video are INCREDIBLE. I FINALLY understand diodes. Thank you!

[@mumiemonstret]

I love your presentation style and voice. It's soothing yet engaged, a rare combination on KZbin.

[@MidgieNerd]

After literally 10 hours, i finally came across this video. Thank God, now I might not fail physics :D

[@kurtronaldesteban8190]

I graduated electronics engineering but this made everything clearer about diodes. Nice!

[@chetlewis6905]

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

[@OhhYasssh]

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

[@AgglomeratiProduzioni]

"Diodes, LEDs and solar panels" --> So diodes, diodes and diodes?

[@trinidad17]

All are diodes, but the first "diodes" you mention are usually called "signal diodes" because of their application.

[@halonothing1]

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.

[@inventorofmachines]

Fries, Chips and Mashed Potatoes

[@mattomanx77]

Very interesting! So what determines how 'efficient' these diodes are?

[@VincentGroenewold]

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.

[@halonothing1]

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.

[@abramthiessen8749]

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.

[@byaafacehead]

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

[@luongmaihunggia]

Tests.

[@mitchese1]

This is the best explanation I've seen of diodes, P-type and N-type gaps. Thanks!

[@francislee7770]

What a great teacher. I like his channel because he takes complicated ideas and deconstructs them to simple explanations. So much respect

[@GeorgePlaten]

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!

[@SteveMould]

This is useful feedback thank you.

[@tmanook]

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.

[@oddzc]

Agreed!

[@catladyrai]

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.

[@nienke7713]

Does a solar diode then also work best from infrared light, or do the visible light photons work just as well?

[@zn4rf]

have a read: www.sciencedirect.com/science/article/pii/S0927024805002345 Or: Depends on the material your "solar diode" is made of.

[@nahfid2003]

@@zn4rf this is not free?

[@amelia_camellia]

This is the best explanation of semiconductors that I've ever seen.

[@Pa1_Thakur]

its amazing how something this simple can be so useful.

[@atechnews3221]

Never gonna look at my TV the same again.

[@scottwilling5315]

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?

[@suddeneevee9441]

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.

[@scottwilling5315]

@@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. 😉

[@VictorQuesada-bl1xk]

Excellent work, thank you for making it so straightforward.

[@gabedarrett1301]

I've been looking for an easy and in-depth explanation for months. You've done it! You have a talent for explaining things well. Subscribed

[@MrMishra814]

Minor correction. The pn junction isn't made by pushing two materials together

[@nicklachen5060]

This isn't really a correction, just pointing out a potential incorrect statement.

[@atmel9077]

This video is simplified, semiconductor manufacturing is another story.

[@PixlRainbow]

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.

[@lordbarron3352]

61 people disliked because they are NEGATIVE. Hopefully they decide to reverse polarity and leave a like :D

[@WaitingForRevolution]

So glad you released a part 2 explaining it all in a more technical but very easy to understand manner. Keep it up! 👍🤘

[@iveharzing]

I honestly understand solar panels way better from this video than from lectures at university, thank you Steve Mould for this video!

[@OceanBagel]

Ok, so what's the deal with zener diodes?

[@upsidedownairline9388]

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.

[@sirplatinius4513]

0/10, nothing poured out of a beaker.

[@andymcl92]

@@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! :)

[@jaytee2395]

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!

[@lawrencerubanka7087]

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!

[@3v1Bunny]

theoretically .. an amoled phone could charge itself when you lay it screen up in the sun ;)

[@honestlymars]

Why has no-one commented on this, even just in banal admiration of the sentiment? We need naturally solar-powered AMOLED phones!

[@shayanmoosavi9139]

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 :)

[@eekpie]

Is Ali D related to Ali G ?

[@saad1653]

Yeah, they're both Ali A's brothers

[@jayankaghosh]

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 :)

[@ayhamsaffar8407]

This was explained at the Oxford uni materials science open day, but i could only follow your explanation. Really appreciate your videos

[@AnimilesYT]

When you were talking about anthropomorphising atoms, the first thing I thought of was 'catoms'. catgirl-atoms. Someone, please draw this xD

[@soslunnaak]

You mean Ions? Cations?

[@Talaxianer]

Press F to continue…

[@OwenBerg]

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.

[@jonnym4923]

I've been wondering how these things work for so long and this was an amazing explanation. I finally feel like I have a high level understanding of how leds and solar panels work. Thanks!

[@XS1GOLIATH1]

I understood diode and led with your video after years. Very simplified and professional. Keep the good work man.

[@kevinocta9716]

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!!!

[@rickbailey7183]

Excellent expository video and animation! The more we understand things, the more uses we can find for them.

[@hithereimjack2252]

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.

[@WickedMuis]

Would love to see more videos like this one about ALL the electric components (transistors, capacitors, resistors, etc.) and how they are used! Love the pace and thoroughness of how it's explained!

[@exponentialvoid]

Very accessible way of teaching this. Thanks for taking the time to make these quality animations.

[@1314zerosktr]

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.

[@Wh4tsupy0]

This is a really great, easy to understand explanation of diodes. Your explanation of n and p type semiconductors in general was also really interesting.

[@JTheoryScience]

this just explained all of the instrumentation trade at its finest detail. wicked explination

[@imranq9241]

This is the clearest explanation of diodes I’ve seen

[@jason.arthur.taylor]

I have a PhD in physics and an option in EE. It's a rare combination. This was the best educational content I've ever seen on these topics, and it was a good use of video in education. Textbooks take myriad pages to say as much!

[@CalebJMartin]

You have a remarkable skill for explaining things! Thank you so much, this was fascinating to watch!

[@JCtheMusicMan_]

Brilliant, easy to grasp explanation of semi-conductors! Keep up the excellent work!

[@kartoffelwaffel]

Fantasic! Well explained and in simple terms, you have a knack for it! Excellent video, thanks!

[@cisarvialpando7412]

Best explanation ever. Today I actually learned how diodes work. And the working of depletion layer......

[@cfink6041]

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.

[@SteveMould]

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.

[@GearDownForWhat]

You explain things is such intuitive ways.

[@Jonahmeans1024]

Absolutely amazing! The best explanation of diodes and LEDs so far. Thank you!

[@smartcat001]

Thank you. The explanation on boron / phosphorus doping is very clear.

[@MartinBodin]

Thank you for this very nice video! You’re explaining something really complex in such a smooth way that it makes it simple. These animations are really well done ☺

[@lucklessluke]

Fantastic way to explain diodes. Love it!

[@dermihai]

What I love is that you take you time, not like other channels, rushing trough special relativity in 2 minutes. Well done.

[@crashjohnny_]

Awesome video! You have a natural talent to explain things. I could spend a whole day watching your videos 😊

[@EvanHotwingsCorgiat]

One of the best explanations of diodes that I have ever seen, great job!