AT&T Archives: Dr. Walter Brattain on Semiconductor Physics (Bonus Edition)

For more from the AT&T Archives, visit techchannel.att.com/archives
Introduction by George Kupczak of the AT&T Archives and History Center
In this film, Walter H. Brattain, Nobel Laureate in Physics, presents an introductory college-level lecture on the physics of semiconductors. He demonstrates by experiment such semiconductor properties as thermal EMF, photo EMF, and rectification. He introduces a simple mathematical model to describe the observed properties of semiconductors.
The history of the development of semiconductors, the impact of new discoveries and some of the new phenomena are also discussed. Dr. Brattain shared the Nobel Prize in 1956 for his co-invention of the transistor. He was a member of the Physical Research department of Bell Laboratories.
Footage courtesy of AT&T Archives and History Center, Warren, NJ

[@FreedomIsNeverEverFree]

College courses of semiconductor physics usually starts from Band-diagram or Fermi-energy, which confuses students. These concepts were not mentioned in the lecture at all. The lecture starts with demonstrating physical phenomena. Physics starts from explaining physical phenomena. The applications of semiconductor devices are their physical phenomena, e.g. amplifying signal, computing, energy harvesting, light-emitting.

[@SomeUserNameBlahBlah]

So true. When I was in college the professors would go right into the quantum mechanical approach without giving a basic picture of what is happening. As I watch these older videos it is clear to me that the truly smart people always give the best and simple answers which increases understanding.

[@fuchong1216]

@@SomeUserNameBlahBlah Agree, the need to understand the solid state diode was because of its need in high frequency radar during WW II. The early pioneers had a pressing problem to solve, with seemingly conflicting data to reconcile. Experimentation and better understanding led to its invention.

[@manudehanoi]

[@JimAllen-Persona]

I agree. This is easily understood and I’ve only had High School physics.

[@JimAllen-Persona]

@@SomeUserNameBlahBlah Feynman’s approach.. if you can explain it simply, you understand it.

[@wasiemqutteneh7346]

I wish I had watched this video before taking my semiconductor course. It is Worth of gold.

[@scenFor109]

Amazing how much basic information was missing from the introduction that I was given to semiconductors. Not really surprising considering that so-called sovereign banks make money from militarily enforced Exclusive Economic Zones commonly known as countries. The cult of sovereign banks know that only ignorant indoctrinated people will accept forced monopoly currency and forced servitude. Remember, a statement of sovereignty is not secular.

[@owlredshift]

@@scenFor109 actually, "considering" all of that, I have no idea wtf the first thing, or the comment you replied to, have to do with sovereign banks. Are you ill?

[@scenFor109]

@@owlredshift Not ever so very much. You?

[@Dr_Mario2007]

This lecture apparently also covered the early LED (at 29:40).

[@bahmanfarnudi563]

Brilliant. A treasure. Thank you AT&T. More please.

[@charlesashurst1816]

I'd never heard it explained so well before.

[@radiorob7543]

Thank You AT&T.

[@pinklady7184]

This is gold. 😍

[@yfs9035]

Thank you for preserving these amazing films!

[@sbrahi]

great people......great work

[@pauldow1648]

Yes. Physical extremes. Temp,pressure,velocity, characteristics of elements.

[@Ihaveanamenowtaken]

The impact... he couldn’t imagine the vast impact of the transistor...

Thank you so much for this video.

[@ramorrisey]

Note at 23:35 how important the domain of purity is. The substrate material needed to be over 1,000 -10,000 times more pure than chemical purity before real progress in electronics could be made.

[@kaushaikpaul8023]

Absolutely remarkable knowledge, thankyou AT&T

[@pushing2throttles]

Ok that was awesome. I was surprised to see him working with germanium as well as silicon. That was some great science!

[@sraiken]

They used germanium first because it was easier to ‘purify’ than silicon, temperature for zone melting process was lower.

[@PencilCrasher]

Thank you !

[@davidweston9115]

After 20 years of study, I finally understand this !! No wonder they are called holes!! And I see now obviously why the semiconductors act this way! It is incredible. I had a similar problem studying integrals in college, never knew what they were until I told an electronics engineer about my problem and he stated in one sentence what an integer was and I understood it. Why can't colleges tell us the real information quickly and simply? Do they gain something from turning out graduates who still don't know what it was they were studying (even if they can make the equations balance out on their tests).

[@davidmaster4873]

one of the best

[@sraiken]

Excellent, thanks. He was a top notch experimental physicist. My idol.

[@godfreecharlie]

A wooden laser pointer! How ingenious!

[@GoSlash27]

I also like the white dry erase marker on the black dry erase board :D

[@JackPassmore]

The entire information age of mankind... in one lecture

[@karelltulod3079]

I LOVE AT&T

[@DiaconescuAlexandru2024]

29:41 I didn't realise the first LED existed in 1959! I thought the first LED was an IR LED made in the 60's.

[@JimAllen-Persona]

Very interesting.

[@JamesGMunn]

What was the "transparent" material? Good lecture!

[@thomassalto9758]

I feel it like real physics!☺😇

[@FidoHouse]

Wow!

[@biznock09]

what does he say at min 30:15? "The most important thing is..." WHAAAAAAAAAAAAAAAAAAAAAAAAAAAAT

[@64etto]

Interessante filmato, soprattutto per la scoperta dei diodi LED ultima parte del filmato costruiti oggi con silicio, germani, selenio, arsenico, gallio, stronzio, alluminio e oro. Nel 1977 a 12 anni d'età ho scoperto un effetto molto più luminoso dei LED in commercio di quel periodo usando per gioco un diodo a baffo di gatto germanio e tungsteno da un kit radio onde medie che stavo studiando. Ho preso tale diodo senza resistore limitatore di corrente e lo alimentato a 9V-10V in corrente continua direttamente ne suo senso di conduzione un bel corto circuito e girato invece inversamente si illuminato di una luce bianchissima, il diodo è il OA85, lo fatto pure vedere a mio caro padre. Nei studi conseguiti poi di radio tecnica e tv soprattutto nello studio dei semiconduttori diodi e transistors e la loro costruzione sia drogati e a punte metalliche di contatto sul semiconduttore di tipo n o p costruito in MS, quella connessione elettronica la si può considerare effetto del fisico ZENER effetto tunnel o a valanga.

[@raymiles691]

My uncle on the (P)hilips side, worked in this area prototyping for the President of Bell & others,I guess you could say, to become very close, other side (M)iles then in UFO Pittsburgh. (Veeerrry Innnnteresting Folllowings)

[@unnilnonium]

I can't understand what he is saying at 5:26: Beginning at 5:22, he says, "... the contacts to them sometimes pass current in one direction banananother." Is he saying, "but not another" ...? (This is what I'm guessing from the demo.) So I listened on to see if he would restate it in another way, when, at 5:32, he gets to, "... One contact has these properties. The other contact izzomie." Can anybody clear this up? I get the idea from the demo, but still.... Thanks.

[@louf7178]

Your first interpretation is correct; "...but not another." The second, "izzomie", I think, is: "is ohming".

[@fuchong1216]

Metal to semiconductor contact is complicated, depending on the contact material and the surface conditions on the semiconductor surface (surface states), the contact can be ohmic (just like a normal metal to metal contact with some resistance) or non ohmic (not an ohmic contact, the metal and semiconductor contact forms a rectifying contact, a diode, allowing current to pass in one direction, but not the reverse direction). Semiconductors are group IV elements in the periodic, inside the material (diamond, silicon, germanium), all the 4 outer electrons are bonded, but not at the surface. These dangling bond attract ions gathering on the surface, changing its property. Also, if there are impurities (usually group III or VI elements), they can change its properties too.

[@fuchong1216]

Note: an ohmic contact is one that follows Ohm's law, current through the contact is proportional to the applied voltage.

[@AlhambraDream]

This guy and Bardeen together invented transistor in Bell labs.

[@riccardocatollacavalcanti]

25:00

[@ramorrisey]

Notice 27:40, the proper use of quantum as something small, not like today's quantum leap. However, 'quantum leap' is not wrong if one understands that in the continuum, changes are infinitely infinitesimal, therefore, even a small quanta in relatively huge.

[@parpaasbarpaas4603]

30:15 what is important to learn is....... we never know they cut it out, why at&t for god love why???????????!!!!!!!!!!!!!!!

[@milesprower6641]

That man in the red shirt, has a fabulous lisp

[@DonaldSleightholme]

i had a idea for a photovoltaic telescope? i wondered if it was possible to get electricity from a distant star at nighttime? 🤔🔭 🤷‍♂️

[@chanakyasinha8046]

Solar cell

[@colejohnson4941]

That's how modern telescopes, or any sort of digital camera works. They use CCDs, or Charge-Coupled-Devices

[@joeygray1984]

"these vacant positions are called holes" lol.

[@josephanderson7237]

Joey Gray An absence of an electron is called a hole.

[@chanakyasinha8046]

Blackhole

[@ceelonium]

#lostmestartingrightaround18:00

[@jb-vb8un]

C - very very funny

[@unnilnonium]

Why is it that everyone in the 50's and 60's said, " uh TALL" instead of , "at all?"

[@louf7178]

I'm not sure why, but it was common to hear "at all" spoken as "a'tall" much prior to that (say, at least mid-1800's), and it must be carry-over, here. It seems to have been annunciation among elites (and copied by many) signaling high status (although he is not being pious and is his, more-less, regular speech); one can tell the effort used in maintaining proper speech (English) for this documentary. That's my guess, and I'm sure that is correct. No big deal, just how it was done.

[@unnilnonium]

Ah.... Thanks. I was just noticing the same trend in just about all of the PSSC films I've found, and even Carl Sagan does it in his RI Christmas lectures from 77. Just something I'm more familiar hearing in a British accent.

[@threeleggedman]

I often hear/read about the "discovery" of the transistor. Wasn't it an invention?

[@rob1248996]

God is speaking.

[@amare65]

Am I the only one here that thinks this dude sounds like Droopy Dog? 🤔

[@50471736]

You are not alone.

[@apareek96]

Thank you AT& T .

[@anandavenkatesh4074]

great people......great work

[@emvdl]

Thank you!

[@johnpro2847]

Very few demonstrations directly affect everyone watching .