Into the Third Millennium

The initial years of the third millennium provided an excellent opportunity for reflection upon the impact that electron devices have had on the world over the past century - and upon the contributions of the individuals and institutions that invented and developed them. Telephone and wireless communications were in their infancy a century ago, and electronic computation did not even exist. Today, thanks in large part to electron devices, people can witness via satellite events on the far side of the globe at almost the moment of occurrence. They can converse over cellular phones from a rapidly growing variety of locations throughout the world. And they can afford to purchase computers whose microprocessors churn away at over a billion cycles per second.

The crowning recognition of achievement in electron devices came when the Royal Swedish Academy of Sciences announced that Jack Kilby, Zhores Alferov and Herbert Kroemer had won the Nobel Prize in physics. Kilby was honored "for his part in the invention of the integrated circuit," while Alferov and Kroemer were recognised "for developing semiconductor heterostructures used in high-speed- and opto-electronics." (Although he clearly deserved to, Robert Noyce could not share in this prize, since he had died in 1990.) Reflecting the increasingly global nature of the discipline, a Texas electrical engineer born in Kansas, a German-born California physicist and a Russian physicist from St. Petersburg would share science's most prestigious prize.

On December 10, 2000 Kilby, Kroemer and Alferov marched onto the stage of Stockholm's Concert Hall to the accompaniment of trumpet fanfares as Bardeen, Brattain and Shockley had done over four decades earlier, walking before two phalanxes of previous Nobel laureates. With an audience of over half a billion watching on television screens across Europe and around the world, lord Claeson, Chairman of the Nobel physics committee, said, “ Few have had such a beneficial impact on mankind as yours." Following that, the three men accepted their gold medals from the King of Sweden, joining such illustrious figures as Albert Einstein, Enrico Fermi and James Watson in the Pantheon of science. It had been a very good year for electron devices.

"The advanced materials and tools of microelectronics are being used for studies in nanoscience and of quantum effects," Claeson had noted in concluding his speech. He confidently predicted that "there will be continued development, as we may be only halfway through the information technology revolution." The events of that year and the next were already beginning to prove him right. The scientific and technological breakthroughs that these three men and others had achieved were still yielding penetrating insights and potentially revolutionary electron devices.

Existing techniques are actively being applied to the fabrication of nanoscale devices such as quantum corrals, wells, wires and dots - in which electrons move in only one or two dimensions, or are trapped around a single point. The explicitly quantum behavior imposed by such a close confinement promises important new applications. The quantum cascade laser developed by Bell Labs is just one example of nanotechnology already being put to practical use, such as measuring the levels of atmospheric pollutants.

Other researchers have managed to fabricate nanoelectromechanical systems (NEMS) in silicon. One such device is an electromechanical transistor developed by University of Munich scientists, in which a single electron shuttles from source to drain upon a silicon pendulum vibrating at frequencies up to 100 MHz. And in June 2001, researchers at Intel announced the fabrication of silicon-based transistors with features measuring only 20 nanometers across. With such ultramicroscopic electron devices, companies can envision one day manufacturing silicon microchips sporting billions of transistors. That very same summer, Motorola scientists announced that they had developed a revolutionary way to mate heterostructures made of gallium arsenide and other III-V compounds with silicon microstructures. This advance promises a whole new generation of microchips that can offer both computational and opto-electronic functions.

Still other scientists and engineers are pushing the electron-device frontiers into domains where they no longer rely on silicon. In April 2001 IBM researchers announced having fabricated large arrays of transistors made from carbon nanotubes. The following August, the same group reported the successful operation of a logic circuit built solely out of such nanoscale components. Meanwhile, Hewlett-Packard scientists have been developing custom-designed carbon-based molecules that can serve as on-off switches. Such "molecular electronics" devices may offer dramatic increases in the performance of the electronic circuits of the future.

The "information technology revolution" spawned by the 1947 invention of the transistor clearly has a long way to go before it runs its full course. The flood of striking innovations that have occurred over the past fifty years, in the wake of this epochal electron device, still shows little sign of letting up.

Exercise 5

Answer the following questions to the text.

1. What impact have electronic devices had on the world over the twentieth century?

2. How fast do modern microprocessors work?

3. Who received the Nobel Prize for the invention of the integrated circuit?

4. What are the most famous developments of Alferov and Kroemer?

5. Was Robert Noyce also awarded the Nobel Prize?

6. What predictions did the Chairman of Nobel Prize physics committee make?

7. Was he right?

8. What are the main features of quantum electronic devices?

9. What quantum device is being used to measure the levels of atmospheric pollution?

10. What where the main developments in nanotechnological research in 2001?

PART 2

Date: 2015-12-24; view: 1168