Silicon, Semiconductors, & Solar Cells: Crash Course Engineering #22

Today we’re looking at silicon, and how introducing small amounts of other elements allow silicon layers to conduct currents, turning them into semiconductors. We’ll explore how putting two different types – N and P semiconductors – together gives us electrical components like diodes, transistors, and solar cells.

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  1. Buried Alive on December 13, 2019 at 1:12 am

    Note that processing Silicon on an atomic level was described in this video however, the terminology describing the process of adding Boron or Phosphorous to Silicon called "Doping" was not correctly identified.

  2. lambda R on December 13, 2019 at 1:13 am

    so good

  3. lsamaknight on December 13, 2019 at 1:15 am

    Quick reminder to everyone wanting to ask about Marie Curie, one of her Nobels was in physics, the other was in chemistry.

  4. Forest Miller on December 13, 2019 at 1:18 am

    When the arrow on the circuit changes direction at 9:14, it changes from saying Electron Flow to Current. This is just to show that the two terms are opposite notations, so the flow didn’t actually change directions right?

  5. giko rin on December 13, 2019 at 1:18 am

    Why don’t we use sulphur in n type semiconductors for better current or do we?

  6. xspager on December 13, 2019 at 1:18 am

    that statement around 7:02 makes no sense, the ability to use a small current to control a large don’t have anything to do with zeroes and ones

  7. Brolic Scholars Fitness on December 13, 2019 at 1:20 am

    Thanks for posting the resources!

  8. MDZPNMD on December 13, 2019 at 1:20 am

    Great job, great video, well explained.

  9. Dylan Fiore on December 13, 2019 at 1:21 am

    And thats just in electronics, because optics is also effected. And biology to.

  10. axelasdf on December 13, 2019 at 1:22 am


  11. Robert Bercovitz on December 13, 2019 at 1:24 am

    super informative

  12. M Singh on December 13, 2019 at 1:24 am

    This episode was more helpful than my classes.

  13. PREDRISING on December 13, 2019 at 1:26 am

    Did anybody else hear "Second was for describing a way that SuS materials can conduct electricity with no resistance"?

  14. Dan Victor on December 13, 2019 at 1:26 am

    You can work and research Semiconductors and solar cells materials following the career of Electrical or Mechanical Engineering.

  15. Greg Lindstrom on December 13, 2019 at 1:28 am

    I want to convert sun energy into electricity ? how is this done???????????????????

  16. SwordQuake2 on December 13, 2019 at 1:30 am


  17. Capital-Asterisk on December 13, 2019 at 1:30 am

    diode bridge? FULL BRIDGE RECTIFIER!!

  18. Riveen Kariyawasam on December 13, 2019 at 1:30 am

    Won’t the holes and electrons cancel out all charges?????

  19. Cell2109 on December 13, 2019 at 1:32 am

    Do one on motors and generators

  20. Nelson Swanberg on December 13, 2019 at 1:32 am

    A professor once explained them to me like this Transistor = Transition/Resistor.

  21. Dream Reaper on December 13, 2019 at 1:33 am

    im commenting on that meta reference btw

  22. Danilego on December 13, 2019 at 1:34 am

    Wow, what a great episode! Semiconductors, transistors and solar power explained

  23. Donald Sleightholme on December 13, 2019 at 1:35 am

    Radioluminescent paint? 🎨🤔🤷‍♂️

  24. Castle师子 on December 13, 2019 at 1:36 am

    All seem foggy

  25. Ivor Wu on December 13, 2019 at 1:37 am

    Guys why are the holes in the P type not cancelled by the B type?

  26. Iron Ballz on December 13, 2019 at 1:37 am

    Woohoo, this is a really good class on BJT’s (Bipolar Junction Transistors) and MOSFET’s, and solar energy. And I really like this girl! She is so skinny and tall and smart! Maybe she can talk about the "small signal model" next time! If your are as cool as I am, do the "small signal model" next time and what the larger and complex reality that this model represent!

    Gracious, gracious, gracious!

  27. Joy Divisione on December 13, 2019 at 1:38 am

    She talks much slower in this series than Physics series. Those Physics ones are all a mess!

  28. hoser119 on December 13, 2019 at 1:38 am

    Does this channel provide any "Try this at Home" Experiments?

  29. MaRsHaLl on December 13, 2019 at 1:39 am

    make a crash course on narcotics

  30. Peter H. van Leeuwen on December 13, 2019 at 1:39 am

    Apart from the good explantation on this major subject in our current society I must say……What a stunning woman. Knowledge, eyes, mouth and hair fitting perfectly in her smooth face. I think I will stay on this channel.

  31. xspager on December 13, 2019 at 1:41 am

    why is a steam engine powered by a solar panel????

  32. 3TE on December 13, 2019 at 1:42 am


  33. Daniel Foland on December 13, 2019 at 1:47 am

    What? 10^-9 up next? That’s like, a crash course cliff-hanger

  34. qwaqwa1960 on December 13, 2019 at 1:47 am

    Of course, virtually NO digital circuits use bipolar (NPN/PNP) transistors now…

  35. Ahn Michael on December 13, 2019 at 1:50 am

    wow I know this is Crash Course, but if you just left tiny spaces in between speech segments (as would happen in normal conversation), I think it would vastly improve comprehension – at least for me, but likely for others, too. there is no pause in which to process that I have understood something before moving onto integrating a new concept.

  36. Adrian Gunnar Lauterer on December 13, 2019 at 1:50 am

    wtf showing a power regulator as the objekt in focus when you talk about transistors?.

  37. Harleen Kaur on December 13, 2019 at 1:51 am

    Your videos are awesome, and these videos were the reason I passed my physics final. Have you guys considered partnering up with the AAMC to make videos geared towards MCAT review?? I would love to watch your videos to review for that content

  38. Dylan Fiore on December 13, 2019 at 1:54 am

    doping: the enhancing of a semicomductors conductance by the altering of the net positve or negative charge by injecting an impurity.

  39. Donovan Zane on December 13, 2019 at 1:55 am

    I watched the entire series in a afternoon,dang learned so much thank you Dr. Shini Somara and crashcourse. I love to hear you talking

  40. Shockwave _123 on December 13, 2019 at 1:57 am

    you are not good so sssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssstttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttttooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppppp

  41. Strawberry Dobreva on December 13, 2019 at 1:58 am

    DC circuits and Marvel circuits

  42. Sabrina Gibby on December 13, 2019 at 1:59 am

    I love this so much!

  43. Triloki Maurya on December 13, 2019 at 2:00 am

    Its so basic

  44. Irwain Nornossa on December 13, 2019 at 2:01 am

    Anything computing uses unipolars, because controlling by field, not current, but I get you’d need another video for explanation of those.

  45. Oeumuepo Stéphanois on December 13, 2019 at 2:02 am

    Please add any suggestions. It’s not like Crash Course needs new ideas lol, but just putting it out there

    Coding logic
    Animal Sociology
    Astrophysics (as a follow up to Astronomy and Cosmology)
    hehe – Maths (split up into 3, 4, 5 thematic parts?)

    Animal Linguistics

    Urbanism and Urban Planning
    Political Theory
    Geopolitical Theory

    Acoustics and Sound Engineering
    Music History – possibly split up into
    _________________Written Western Music History
    _________________World Popular Music History

    _________________Asian Written Music History
    _________________World Written Music History
    Music Theory – possibly split up into
    _________________Tonal Music Theories
    _________________Greek, Medieval and Renaissance Western Music Theories
    _________________African Music Theories
    _________________Music Theory (others, like Indian, dodecaphonic, Messiaen etc)

  46. Yamen Nazer on December 13, 2019 at 2:02 am

    This is amazinggg

  47. Duffy Elmer on December 13, 2019 at 2:03 am

    I wish these showed up in my subscription box

  48. Jared Kaiser on December 13, 2019 at 2:04 am

    The transistor mentioned is a BJT Transistor, not the more commonly used MOSFET Transistor.

  49. jeff nguhiu chege on December 13, 2019 at 2:06 am

    I have to say that’s one of the best explanation of transistors, with this explanation one can slowly but surely build up their knowledge in what is arguably the most important electrical component of our time

  50. Anomalies on December 13, 2019 at 2:08 am

    i love that, ‘to do:make meta reference in episode so people in the comment section comment on it’ lol 🙂

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