At present, electronic watches are quite common. It can display the hours, minutes and seconds, as well as the days of the month and the week. Some electronic watches have more functions. For example, some can display the time around the world; Some can also measure your temperature, pulse and blood pressure.
Why does a small electronic watch have so many functions? It turns out that integrated circuits are used in electronic watches.
Integrated circuit is a kind of semiconductor device. From the appearance, it is just a rectangular sheet the size of a nail, with many metal "long legs" sticking out around it. If you open its shell, you will see a silicon wafer the size of a grain of rice inside. Looking carefully at the silicon wafer of the silver glittering integrated circuit with the naked eye, we can vaguely see that there are many patterns on its surface. If you put the silicon wafer the size of rice grain under the microscope, it's like overlooking a city on an airplane. You see, silver roads crisscross. There are many blocks like buildings on both sides of the avenue. There are many large blocks on the periphery of the silicon chip, which are like a city's railway station, bus station and airport. It turns out that the blocks like buildings are electronic components such as transistors, resistors and capacitors; The silver Avenue is the connection between electronic components; The larger blocks on the periphery are pressure welded joints, which are pressure welded with thin silicon drill wires. These silicon drill wires connect the pressure welding joint with the metal "long legs" on the shell. The current that transmits all kinds of information flows in and out here. This is an integrated circuit, just like a busy pocket "Electronic City".
The world's first integrated circuit was developed in 1959 and contained only a few electronic components. In the next two or three years, medium-sized integrated circuits containing hundreds of electronic components soon appeared. By 1967, large-scale integrated circuits that could accommodate thousands of electronic components also appeared. By 1977, there was a very large-scale integrated circuit that could accommodate more than 1.2 million electronic components on a silicon chip the size of a soybean grain. At present, 150000 electronic components can be accommodated on a small silicon wafer. The continuous development of integrated circuits, especially the emergence of large-scale and super large-scale integrated circuits, has greatly reduced the volume, weight, reliability and cost of electronic equipment. At the same time, it also makes the functions of electronic equipment more and more. In this way, integrated circuits are widely used in various fields. At the same time, it promotes the rapid development of integrated circuits. It is estimated that the capacity of integrated circuits may grow to 1 billion semiconductor components in the future. At that time, it will become the "big electronic city", not the "big electronic city".