Shadowing Practice: What Is A Semiconductor? - Learn English Speaking with Video

Science!

Here I have a circuit with a battery, light bulb, and gap.

If I fill this gap with a metal, the light comes on.

If I fill this gap with glass, the light stays on.

You probably already know this because metal is an electric conductor and glass is an insulator.

But what happens when I fill this gap with a silicon wafer? wafer.

The light stays off so you might think the silicon is an insulator but what if I heat it up?

Thank you.

It lights up.

The silicon is insulating at room temperature but conducts electricity when it's very hot.

It's a semiconductor, whose conductivity changes based on the environment.

This special ability makes semiconductors the perfect brains for electronic devices.

Circuits of small semiconductor switches,

called transistors, are at the heart of computer chips and enable them to do math and run programs.

Semiconductors have enabled electronics to become smaller, faster, and more reliable.

But what is it exactly about these semiconductors that allow them to either conduct or insulate?

In a single atom, electrons can occupy specific energy levels.

When multiple atoms bond, the electrons are shared between them.

But because the atoms are now interacting,

the energy levels shift around.

In a solid, trillions and trillions of atoms interact with each other.

Their individual energy levels smear into energy bands.

For a material to conduct,

the electrons must be able to jump from lower energy states to higher ones.

The spacing of these energy levels and how they're filled with electrons determines if if the material is a conductor,

insulator, or semiconductor.

If there's a huge gap between the lower energy levels and the higher ones,

it's hard for electrons to jump to the higher ones,

so current can't flow, and it's an insulator like this glass.

Metals have no gap at all.

Electrons can move to the higher energy levels with no problem.

Current can flow.

Semiconductors fall somewhere in the middle.

They have a medium-sized band gap.

So technically, I can make this glass conduct electricity

if I added enough energy through heat to push the electrons into a higher band.

But that amount of heat would either melt or break the glass before it actually conducts.

This is true of most insulators.

The amount of energy needed to make them conduct is just too high.

But in a semiconductor, the band gap is small enough

that electrons can jump into the higher energy band so that current can flow.

The amount of heat we apply determines how many electrons jump into the higher band and how much current flows.

And heat isn't the only way to change the conductivity in a semiconductor.

We can also use light,

electric currents, and in a computer, electric fields.

As I've said, computers are made up of semiconductor switches called transistors that switch between conducting and insulating.

Computers use electric fields because heat is slow and would burn too much energy.

We can turn this wafer into a computer chip by printing a circuit of transistors on it using a process called photolithography.

Here, in the photo room,

we cover the wafer with a light-sensitive material and expose it to light that we shine through a pattern mask.

Then, we develop the wafer,

like film and photography, which leaves behind a pattern that becomes the circuit.

Printing the transistors at once lets you make circuits that are smaller and cheaper than if you built them from individual parts.

Transistors make up the logic elements,

the memory components, and the communication modules that let computers talk to each other.

With semiconductors, you can cheaply add transistors to almost any device you can think of,

from spaceships to servers to maybe even your toaster.

Semiconductors have enabled the technological revolution,

the internet, the computer, and the cell phone.

No semiconductors, no information age.

I'm Jamie and thanks for watching this episode of Science Out Loud.

Be sure to check out some of our other videos,

including mine, on how computers compute.

Check out our website for more information.

The end is...

I'm just like...

✨ Recomendar Video

20 oraciones

Vocabulario y notas de pronunciación para esta lección

Esta lección de conversación de nivel C2 se basa en el vídeo “What Is A Semiconductor?”. Las palabras que más se repiten: semiconductor, energy, electrons, gap, computer. Este vídeo tiene 66 frases y 690 palabras para practicar shadowing. La parte hablada dura 4:43. El hablante mantiene un ritmo constante de unas 146 palabras por minuto, cómodo para el shadowing. Solo el 78 % de las palabras está entre las 3.000 más comunes del inglés, por lo que el vocabulario es exigente.

Vocabulario clave de este vídeo

Las 15 palabras más avanzadas del vídeo, con su pronunciación y significado:

Palabra	Pronunciación	Significado
semiconductor sustantivo	/ˌsɛmikənˈdʌktə/	semiconductor
transistor sustantivo	/tɹænˈzɪs.tɚ/	transistor
insulator sustantivo	/ˈɪn.s(j)ə.leɪ.tə(ɹ)/	aislante
wafer sustantivo	/ˈweɪ̯fɚ/	oblea, barquillo
atom sustantivo	/ˈætəm/	átomo
insulate verbo	/ˈɪnsʊleɪt/	aislar
silicon sustantivo	/ˈsɪləˌkɑn/	silicio
conductivity sustantivo		conductividad
conductor sustantivo	/kənˈdʌktɚ/	director
interact verbo	/ɪn.təˈɹækt/	interactuar
compute verbo	/kəmˈpjuːt/	computar, calcular
spaceship sustantivo		nave espacial, astronave
toaster sustantivo	/ˈtəʊ̯s.təː/	tostadora, tostador
bulb sustantivo	/ˈbʌlb/	bulbo, cabeza
module sustantivo	/ˈmɑd͡ʒul/	módulo

Phrasal verbs que vas a escuchar

Palabra	Pronunciación	Significado
check out verbo		investigar, chequear
light up verbo		iluminar
make up verbo	/ˌmeɪk ˈʌp/	reponer, suplir

Gramática en este vídeo

Las estructuras que más usa el hablante, con las palabras exactas del vídeo:

Estructura	En el vídeo
Present perfect have/has + participio pasado — una acción pasada que sigue importando ahora	have enabled · I've said
Voz pasiva be + participio pasado — importa lo que ocurre, no quién lo hace	are shared · are made

Pronunciación a tener en cuenta

El hablante usa 6 contracciones y formas reducidas, como I'm, can't, I've. Dilas en su forma corta, tal como las oyes.

Palabras largas — cuida el acento: semiconductor /ˌsɛmikənˈdʌktə/, insulator /ˈɪn.s(j)ə.leɪ.tə(ɹ)/, technological /ˌtɛk.nəˈlɑ.dʒɪ.kəl/

Sonidos difíciles para hispanohablantes:

/z/ — sonora, no /s/: transistor /tɹænˈzɪs.tɚ/, expose /ɪkˈspoʊz/
/dʒ/ — no es la “y” ni la “ch”: module /ˈmɑd͡ʒul/, technological /ˌtɛk.nəˈlɑ.dʒɪ.kəl/

Cómo practicar con este vídeo

Escucha el vídeo entero una vez sin hablar y anota las palabras que no conoces.
Haz shadowing frase por frase a velocidad normal, repitiendo cada una hasta que tu ritmo coincida con el del hablante.
Grábate y compara con el original, prestando atención a palabras como semiconductor, transistor, insulator.

¿Qué es la Técnica de Shadowing?

Shadowing es una técnica de aprendizaje de idiomas respaldada por la ciencia, desarrollada originalmente para la formación de intérpretes profesionales y popularizada por el políglota Dr. Alexander Arguelles. El método es simple pero poderoso: escuchas audio en inglés nativo y lo repites en voz alta de inmediato, como una sombra que sigue al hablante con solo 1-2 segundos de retraso. A diferencia de la escucha pasiva o los ejercicios de gramática, el shadowing obliga a tu cerebro y músculos de la boca a procesar y reproducir simultáneamente patrones de habla reales. Las investigaciones muestran que mejora significativamente la precisión de la pronunciación, la entonación, el ritmo, el habla conectada, la comprensión auditiva y la fluidez al hablar, convirtiéndola en una de las metodologías más efectivas para la preparación del IELTS Speaking y la comunicación en inglés en el mundo real.

Técnica de shadowing: lee la guía completa paso a paso →

Shadowing Practice: What Is A Semiconductor? - Learn English Speaking with Video

The Semiconductor Production Process Explained Clearly

What science can’t answer, according to physicist Jim Al-Khalili | Big Think

Your Skeleton Is Electric

Candy Corn In Space

Nanotechnology and Its Applications

Why Walls STOP Light Waves But Not Radio Waves?

The Building Blocks of Everything: Matter & its Properties

The Absurd Engineering Behind the Internet

We Can Now Simulate a Human Brain, Scientists Show

2 The Principle of the Electron Microscope

Diodes Explained - The basics how diodes work working principle pn junction

Homeostasis - How Your Body Keeps its Balance - Physiology Series