Grammar. Types of semiconductors

Vocabulary

Listening

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TYPES OF SEMICONDUCTORS

Speaking

6. Imagine that you have an interview with a semiconductor engineer what questions concerning the topic you would ask him. Work in pairs, make dialogues.

1. Write the abbreviations from the box next to the words and phrases. Which word or phrase is not about semiconductors? Underline it.

Si InP Cu SiGe GaAs Ge GaP InAs SiC GaN InSb C

1. indium phosphide

2. silicon carbide

3. copper

4. gallium nitride

5. indium arsenide

6. gallium phosphide

7. silicon

8. indium antimonide

9. silicon germanium

10. carbon

11. gallium arsenide

12. germanium

2. Listen to the text and name the types of semiconductors.

3. Listen again and mark the statements below (T) true or (F) false.

1) There are intrinsic and extrinsic semiconductors.

2) Intrinsic semiconductors have good conductivity.

3) A hole is a positive charge.

4) Doped semiconductors are poor conductors.

5) The process of producing hole-electron pairs is called doping.

6) Introducing impurities into the semiconductor materials is called thermal generation.

7) Semiconductors are available as elements and compounds.

4. Find the antonyms or opposite meanings of such words:

1) elements

2) intrinsic

3) negative carriers

4) n-type semiconductor

5) impure

5. “To be, or not to be: that is the question…”

The Greek sea god Proteus was, like the sea, capable of changing form in an instant. Proteus knew all things – past, present, and future – but disliked telling what he knew. In order to get any decent information out of him, you had to grab him and hold on tight while he went through his various forms – lion, wild bear, snake, tree, running stream – it wasn't easy.

The verb “To be” is the most “protean” of the English language, constantly changing form, sometimes without a clear pattern. Considering that we use it so often, it is really too bad that the verb “To be” is the most irregular, slippery verb in the language.

Here are some forms of the verb “To be” in the sentences from the text you have listened to about the types of semiconductors.

An intrinsic semiconductor material is chemically very pure.

Whereas an extrinsic semiconductor is an improved intrinsic semiconductor.

Holes and electrons are responsible for current in semiconductor materials.

These carriers are produced as a result of thermal agitation of the atoms, even at room temperature.

Semiconductors are available as either elements or compounds.

The verb “To be” is used in the following patterns:

1) with a noun:

Silicon is a semiconductor.

2) with an adjective:

The electrical conductivity of intrinsic semiconductors is poor.

3) with the - ed form to make the Passive Voice:

This process of producing hole-electron pairs is called thermal generation.

Semiconductors were discovered in 1874.

4) There is / There are:

There is a semiconductor material in each modern electronic device.

There are intrinsic and extrinsic semiconductors.

5) This is / These are and That is / Those are:

This is a p-type semiconductor.

These are doped semiconductors.

That is germanium.

Those are compound semiconductors.

Basic Tense Forms of the verb “To Be”
	Present	Past	Future
Simple	I	Am	was	will be
he/she/it	Is
you/we/they	Are	were
Perfect	I/you/we/they	have been	had been	will have been
he/she/it	has been

6. Let’s take a closer look at the Present tense forms of the verb “To be”. The following tables include the affirmative or positive form (+), the negative form (–) and the interrogative or question form (?). Complete the tables.

Affirmative (+)
The Verb “To be”	Contracted	Example
I am	I’m	I am a teacher.
You …	You’re	You are a student.
He …	He’s
She is	She…
It …	It’s	It … a semiconductor.
We …	We’re …
You are	You …	You … students.
They …	They …

Negative (–)
The Verb “To be”	Contracted	Example
I am not	I’m not	I am not a student.
You are not	You’re not	You aren’t	You … not a teacher.
He …	He’s not	He isn’t
She is not	She’s not	She …
It is not	It …	It isn’t	It is not a semiconductor.
We …	We’re not	We aren’t
You are not	You…	You aren’t	You are not teachers.
They …	They’re not	They …

Interrogative (?)
The Verb “To be”	Short answer (+)	Short answer (–)
Am I a teacher?	Yes, I am.	No, I am not.	No, I’m not.
Are you a student?	Yes, you are.	No, you … not.	No, you’re not.	No, you aren’t.
Is he …?	Yes, he …	No, he …	No, he’s …	No, he isn’t
… she …?
… it …?
Are we...?	Yes, we are.	No, we …	No, we’re not	No, we …
…you…?
…they…?

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