Photoelectric effect and semiconductors (1 Viewer)

[Saintly Devil]

How did the discovery of the photoelectric effect lead to the discovery of semiconductors?

 

[whiz]

thw whole idea of electrons moving from valence to conduction band, there's heaps of info in the excel book

 

[Saintly Devil]

what does electrons moving from the valence band to the conduction band have to do with the discovery of semicoductors??

The band theory is just a way of explaining conduction and the movement of electrons in substances.

What I want to know, is that how did the discovery of the photoelectric effect (i.e. electrons being released from their atomic structures by electromagnetic radiation) lead to the discovery of semiconductors?

it was an answer in the Surfing series of books - Ideas to Implementation. pg. 40, question 4) c)

 

[...]

i thought the idea of photoelectric effect lead to the discovery of solar panels...(or anything like it)

 

[underthesun]

discovery of photoelectric effect was just accidental by hertz, and then after Max Playnke said his photon thingy, einstein got the noble price for it in 1905 right?

I think the photon theory just fits very nicely with the photoelectric effect, and that's what's important about it. Right?

 

[jims]

that sounds about right.

i read something that said that the theory behind the functioning of transistors n stuff can only be explained in terms of quantum theory, not that classical crap.
or mayb that was superconductors. mayb both. anyway, i dont think theres ne thing that tells u to link photoelectric n transistors because theres nuthing that asks u to explain how a transistor works. which is lucky becoz i have no idea.
u havee to link einsteins photo with blackbodies tho.

 

[Mathematician]

.....

This is probably dumb(im making it up now)

But we know that

conduction only happens in a semi conductor if extra energy is given to the semiconductor(by thermal or other forms..)

And we know that
Conduction happens when electrons move into holes.

Well obviously there is no way of an electron moving into a hole unless it is removed from its respective atom first.

I think this is done only when extra energy is given to the semi-conductor and hence the atoms in it. ( ie by the photoelectric effect)

oh wait thats not the photoelectric effect , the energy must be provided by light .. but i think we used the reasoning or something of the photoelectric effect for other energy as we know all energy is quantitised and have quanta ( and can be other than photons in thermal energy but still being a particle that can transfer its momentum to the electron to liberate it from the atom).

OH WAIT , THE PHOTOELECTRIC EFFECT IS WHEN AN ELECTRON IS LIBERATED FROM A SURFACE LOL , POSSIBLY AN ATOM TOO?
SAME REASONING? BLAHBLAHBLAH......

 

[Giant Lobster]

Originally posted by Saintly Devil
How did the discovery of the photoelectric effect lead to the discovery of semiconductors?

I dont think they are related at all... Semiconductors were originally thought up by some dude working at Bell labs, and since then a team of 3 invented the semiconductor.

The photoelectric effect was discovered by einstein, through using planck's quantum theory of quantised packets of light, and the assumption of an electron can either accept or reject totally a photon.

However these two things are linked in how solar panels...
where did you get ur original statement anyway? if its true, then im really mistaken about a lot... lol

 

[Saintly Devil]

Originally posted by Saintly Devil
it was an answer in the Surfing series of books - Ideas to Implementation. pg. 40, question 4) c)

 

[Saintly Devil]

Re: Re: Photoelectric effect and semiconductors

Originally posted by Giant Lobster
Semiconductors were originally thought up by some dude working at Bell labs, and since then a team of 3 invented the semiconductor.

that doesn't make sense to me. i think you mean transistors.

Originally posted by Giant Lobster
I dont think they are related at all

Hmm....that seems quite possible. could be just a typo in the book. Does anyone know if there are any natural elemets that are semiconductors? Because if there are, they would have been discovered ages before the photoelectric effect was discovered, meaning the question would be wrong. Hmmmm......

 

[Constip8edSkunk]

hmmm...i never knew photoelectric effect led 2 the discovery of semiconductors.... can anyone actually confirm this besides just a single question? perhaps its talking about the development of phtovoltaic cells using semiconductors?

The photoelectric effect was discovered by einstein,

it was first described by Hertz using his spatking reciever and then expanded upon by various other scientists like hallwachs and thomson so it can be demonstrated in a wider range of ways. Einstein was the first to explain it, by using plancks theories...

Hmm....that seems quite possible. could be just a typo in the book. Does anyone know if there are any natural elemets that are semiconductors?

Silicon and germaniam are both intrinsic semiconductors but require higher temperatures to have semiconductive properties. Doping (extrinsic) just makes it easier. dunno when this was discovered tho

EDIT: if it was a question in surfing, does surfing make any mention towards this subject?

 

[Giant Lobster]

Re: Re: Re: Photoelectric effect and semiconductors

Originally posted by Saintly Devil
that doesn't make sense to me. i think you mean transistors.

oh my... how embarrassing
yeah thats what i meant... i got semiconductors and transistors mixed up omg

yeah semiconductors occur naturally, thats for sure. germanium and silicon crystals are intrinsic SCs as mentioned earlier, and they were discovered long before the photoelectric effect.

the only link mentioned in detail in the hsc course are the mechanics behind solar cells. (using the photoelectric effect to liberate electrons at different layers of extrinsic SCs, and forcing them to travel an external route, doing work)

sorry bout the confusion i added earlier about bell labs haha... dont think physics after doing english assignments!

 

[inasero]

ahha no even then the discovery of the photoelectric effect did not lead to the discovery of transistors as such, but was rather an application brought about through alternating layers of positive and negative type semiconductors? wont u agree with me here?

to illustrate my point, lets consider the wheel; its discovery did not lead to the invention of the car, but rather the car was one application which utilized the effectivess of this development...get my drift? i know- trivial, but still important

 

[Nedzy]

can someone explain to me what the photoelectric effect is? i just had my trial today and i couldnt answer the photoelectric effect?
whats a threshold frequency???
SOMEONE HELP ME.....please?

 

[Constip8edSkunk]

it is the observation that electrons are emitted when EMR of certain frequencies are shined upon the metal. this can b seen in a charged elctroscope where only ultraviolet or EMR of higher frequency caused the leaf to fall ie to discharge (electrons to air)
different metals have different threshold frequency that will cause an emission of electrons, that is emr of lower frequency than this would cause no effect. emr of higher frequencies cause electrons to be ejected at higher kinetic energy. its also observed that the intensity of teh light had no effect on whether electrons r emitted, but only the number of electrons emitted.

einstein explained this by imagining each atom absorbing 1 photon. each atom require a specific energy 2 b inputted so that the electron may bcome excited enuf 2 b ejected. and this energy must come from the photon. usinf E=hf, u can determine the frequency corresponding wif this energy. greater frquency = greater energy inputted and these are trans4md in2 kinetic energy proportionally. intensity refers 2 the no. of photons, hence, greater intensity=more photons=more electrons ejected, but hav no say in whether they r ejected or not as it does not rel8 2 energy of photons