Раздел 3 Второе занятие

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functions performed by electronic circuits or even whole systems. Its goal is to rearrange the internal physical properties of the solid in such a way that phenomena occurring within or between domains of mole­cules will perform a function ordinarily achieved through the use of an assembly of electronic components.

Molecular electronics is the most forward-looking of several mod­ern approaches to the development of small, reliable, efficient electron­ic systems. Almost all of them attempt to perform the required electron­ic functions in solid semiconductor-type materials. Molecular electronics, however, is unique in its goal of going away with the tradi­tional concept of circuit components. Should this goal be fully realized, or even partially so, it would extent the capabilities of electronic systems well beyond that which can be achieved today. In addition to lowering size and weight, increasing reliability and reducing power requirements, molecular blocks could make possible the execution of tasks now too complex to be performed economically by conventional methods and permit the performance of electronic functions which cannot be achieved at all with lumped (отдельный) components.

4. Проверьте, как вы сумеете перевести данное стихотворение.

Текст 3.7 В

Прочитайте отрывок из стихотворения “Chip Fabrication”, написанного одним из редакторов журнала IEEE Transactions on Electron Devices. Дайте подстрочный (или стихотворный) перевод.

Chip Fabrication

We use an essential trick

With gallium and arsenic

To make the crystals that we need;

A fabrication line to feed.

We heat them up until they fuse,

A pressure cooker’s what we use.

We put a perfect crystal in And then we draw it out again.

10*

Микроэлектроника настоящее и будущее

And so a bigger crystal grows For hours and hours and no one knows Exactly what it’s going to be Until it’s finished. Its O.D.

Is constant or approximate.

And some of us can hardly wait Until to cylinder its ground And cut in slices almost round And polish till you see your face.

Of any defects there’s no trace.

And now the part the growers hate,

Wfe have to start to fabricate.

5. Учитесь говорить.

15. Ответьте развернуто на следующие вопросы:

1. What is the physical nature of semiconductors?

2. How does semiconductor behave at lower than room temperatures?

3. Why is a crystal of pure silicon a poor conductor?

4. What is the process of doping?

5. In what ways are the areas to be doped defined?

6. What are the main dopants?

7. What role do the holes play in the conduction process?

8. What particles are the carriers of electric current in a p-type semi­conductor?

9. What is the simplest semiconductor device and how does it operate?

10. What technological processes are used in the fabrication of inte­grated circuits?

11. What is understood by the planar technology?

12. How are the problems of tighter control of impurity diffusion solved?

13. Which techniques are referred to as direct methods of film prepa­ration and which of them as indirect? (Describe briefly each of the techniques used.)

14. What makes the automation of crystal growing equipment a ne­cessity?