The integrated circuit consists of layers upon layers of electronic components. A single chip may contain over 100,000,000 tiny pieces. All of these parts must be arranged precisely on the chip, or the integrated circuit will not work. This precision is so exact that the pieces of an IC must be placed correctly within a fraction of a micron. A micron is 1/1,000,000 of a meter or about 1/100 the thickness of a strand of human hair. That's incredibly small!
Below are a few magnified images on an integrated circuit photographed with the microscope. The white arrow points to a human hair which was photographed along with the IC. In the same picture, the white boxes show the connection through witch the electric message enters the circuit. The next three pictures are further magnifications. The white bar indicates a distance of one hundred micrometers or 1/10 of a millimeter. Note that the copyright of this chip is 1982! Sixteen years later, integrated circuits are even smaller with more pieces than this one.
The main component of an integrated circuit is called the transistor. A transistor is a device which controls or generates electrical signals. When you press a button on the mouse, an electric "message" is sent. The transistors within the IC interpret this signal and determine where the message goes next. When integrated circuits were first created in the late 1950's, only a few transistors could fit on a single chip. Now, tens of millions of transistors can fit during production. The speed of integrated circuits has dramatically increased while the size and cost have decreased.
The production of an integrated circuit is a complex process as well. Before an IC can be produced, it must be planned out in advance. Blueprints are made which show how to produce each individual component and its placement. These drawings of an integrated circuit are more complex than a street map containing every road in the world! Some images of these "roads" at further magnifications are shown below. The top two images were taken with the optical mircoscope, and the final three were taken with the scanning electron microscope. Months and months of design go into the production of a single chip. A great web page illustrating the production of an integrated circuit is found at Intel, a leading manufacturer of microprocessors.
Today, mass production of integrated circuits is possible. We can find these little chips everywhere, in almost every electrical device. Besides being perhaps the greatest invention of the twentieth century, their creation could be considered one of the greatest human achievements of all time!
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Last Updated: 6/29/98