Dry Process Technology

LSI Technology has been the cutting edge of the innovate semiconductor industry. In the field of the process technology, much effort has been made to improve microfabrication and thin­ner-film formation technology. In particular, improvements in photolithographic and etching techniques are the keys to the inte­gration of more devices on smaller chips, increases in circuit per­formance, and improvement in wafer process yield.

Dry etching technology represents a new and exciting method for defining precise images in insulators, semiconductors, and metals. Gas plasma etching technology in dry process like RF sputtering, ion beam milling, reactive ion etching, and reactive ion beam etching is widely used as a fundamental tool for the fabrica­tion of MOS, bipolar LSIs, discrete devices and hard mask. It re­sults in improved image size, simplification of the manufacturing process, precise shape control of fine patterns, and development of a cleaner manufacturing process, compared with conventional wet chemical etching processes.

Recently, MOS LSI has sriifted from LSI phase to VLSI phase, which requires a precise pattern less than 3 µm. This tran­sition can be achieved by progress in wafer process technology, in­cluding microfabrication as well as device and circuits design technologies. Conventional plasma etching is not adequate in VLSI regions for the delineation of precise patterns because of its inherent undercutting (подтравливающий) effect which results in anisotropic profile of an etched pattern.

Dry etch technologies available for LSI processing are classi­fied into plasma etch, sputter etch and ion beam etch, with items such as etch mode, apparatus and reaction mechanism.

Определите контекстуальное значение выделенных слов.

3.22. Переведите, обращая внимание на контекстуаль­ное значение слов due to, appear, advance:

1. The numerical value of the conductivity changes due to the concentration of impurities. 2. The significance a semiconductor achieved is due to the electrons being raised to the conduction band. 3. Current due to holes injected into the collector from the base can be neglected since it is very small. 4. New design tools and development systems are appearing. 5. The limiting point appears to be between 10 and 30 Ohms. 6. Recent technological advances in software development are now opening new hori­zons. 7. The advances made by device fabrication have allowed all functions to be integrated onto just one chip.

3.23. Выявите контекстуальное значение выделенных слов без словаря:

1. More efficient communication demands a continually in­creasing level of control in progressively-thinner layers. 2. The extension of any semiconductor technology to small dimensions brings with it a host of new technology, physics and engineering challenges.

Учитесь говорить.

3.24. Подготовьте сообщения по следующим темам:

1. Film technology and semiconductor technology. 2. Silicon for microelectronics. 3. Oxidation and its function. 4. The tech­niques for the deposition of thin films.

3.25. Докажите правильность или ошибочность следу­ющих высказываний. При доказательстве используйте следующие выражения:

I'm not sure that...; the drawback to the (...) is that it is not useful for...; it requires a complex procedure...; it is expensive....

1. Plasma technology is presently in wide-spread use in the semiconductor technology. 2. Molecular electronics is the most forward-looking of several modern approaches to the develop­ment of small, reliable, efficient electronic systems.

МАТЕРИАЛЫ ДЛЯ САМОСТОЯТЕЛЬНОЙ ВНЕАУДИ­ТОРНОЙ РАБОТЫ

(ПОСЛЕ ВТОРОГО ЗАНЯТИЯ)

Учитесь читать и переводить.

Текст 3.12. Прочитайте текст. Изложите свои выводы о преимуществах приборов на арсениде галлия. Используя рисунок, опишите принцип действия прибора. На основе прочитанного и ваших знаний по специальности подго­товьте сообщения о: а) технологии полупроводниковых приборов и ИС; б) новых материалах и новой технологии производства ИС, БИС и СБИС.