Ortografia

Title: Transistors: the Building Blocks of Modern Electronics Hardware

Name: Mohammad Abbas Reza
Major: CIS
Expected graduation year: December 2004

Associated class or project: COMS 320
Professor sponsoring this work: Dr. Rebecca Bates

Date of submission: April 24, 2003

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All sciences have building blocks that define the nature of technology for that science.
For instance,biology, the study of life has cells as building blocks. Cells are the most basic unit
of life and yet the cell itself is a very intricate and complex structure. This intricacy and
complexity is reflected in the technology of life. Similarly, transistors are considered to be the
building blocks of modern electronics hardware. Nature’s technology has been evolving over
millions of years andsimilarly hardware technology has also been evolving since man first
invented the wheel. Transistors have come a long way since they were used for the first time in
the 1940s. Although the basic principle behind them has remained the same in that they all
exploit the same property of semiconductors, the materials used to make them and their sizes
have improved dramatically to register a correspondingimprovement in contemporary
electronics. This paper illustrates the role of transistors as the basic building block for modern
day electrical hardware.
So where does a transistor fit into our world? Their development over the years has
evolved so that they have metaphorically taken on one of the properties of air – they are all
around us. From the most common electrical appliances to industrylevel machinery, they all
depend on transistors to perform their respective tasks. There is a seemingly never-ending list of
electrical devices that make use of transistors. Some that we tend to take for granted in our
everyday lives are our digital alarm clocks, desktop computers, wristwatches, television remote
controls and the television sets that they control. What we take for granted wasscience fiction
six decades ago. This paper presents an evolutionary history of transistors with a brief look at
future possibilities.

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Transistors: A revolution is started
The predecessor of transistors, the vacuum tube was invented in 1904 by John A.
Fleming (“Electron Tube”). The first and the simplest type of vacuum tube is the diode, which is
similar to a light bulb. Althoughvacuum tubes are not the focus of this paper, we have to briefly
examine them to understand the reasons that drove researchers to find a substitute for them. A
vacuum tube consists of a glass tube and a filament much like a light bulb. Their similarity to a
glass bulb does not end there. Being made of glass they are delicate and having a filament means
they emit heat and light. Vacuum tubes wereused as one-way switches and signal amplifiers in
devices such as hearing aids and radios.
While the logic used in vacuum tubes gave rise to many new and popular inventions like
the radio, the size and the delicate nature of vacuum tubes coupled with their high-energy
consumption worked to counter that popularity. The vacuum tube was also an inefficient
component because much of the energy itused was dissipated in the form of heat. The demand
for portable electronic devices as well as the inefficient nature of vacuum tubes spurred the
research for an alternative that would ideally function in the same way but would leave out the
‘negatives’ of the vacuum tube.
As engineers and inventors realized the potential of the vacuum tube, new inventions
appeared on the scene. Almost allelectrical devices used the vacuum tube as a basic component
and vacuum tubes dominated the electronic component industry from early 1900s to late the
1940s. In 1939, Walter Brattain and William Shockley started work on a replacement for vacuum
tubes. After their first attempt was unsuccessful, they set aside their research during the World
War II. They returned to their work in mid 1940s with...