Grmena Abstract

There is a divided type of substances that is named quasi-conductors. People got known about such substances in the end of the 19th century, but just in the 20th century scientists managed to get more knowledge about them. In 1923 Russian physicists proved the ability of usage of semiconductor-metal contacts to accelerate the producing of fluctuations. But such devices as igct which are used nowadays were invented significantly later. First transistor was developed in Bell's laboratory in 1949. This event influenced the quick development of semiconductor devices. Since then many persons all over the world become interested in such type of substance as semiconductors.

Many scientists perform a great deal of researches simply to gain more knowledge about such characteristic of semiconductors as stimulated radiation. The first laser system was created with utilizing of semiconductors. The first variant was based on p - n barriers, the latest ones - on heterojunction.

In case you need some hi-tech devices as for instance asymmetric GTO thyristors, that is not a trouble, actually. There are a lot of developers which propose such. Semiconductor substances have been researched for not so long but radio electronics and lots of other sciences can't do without utilizing of them.

The basic reason why semiconductors are considered to be the detached class is that they have got a conductivity that is between the conductivities of metals and isolators. Such matters as germanium, silicon, selenium and several others are considered to be semiconductors.

It sounds a bit strange but scientists didn't want to carry out researches of semiconductors for a long time. The first man who decided to get more knowledge about semiconductors was Abram Ioffe - Russian physicist. He found that this wonderful type of substance has some unique characteristics and described how they may be utilized. Every semiconductor device has such main characteristics as electron and hole conduction. Such features can be modified by usage of adding some admixtures or modifying temperature. For instance, by usage of some admixtures the value of electron conduction may be modified.

Almost every sphere of modern technologies implies usage of semiconductors. Diodes, transistors and thyristors are the most often used devices. The broad application of semiconductors started not so long ago but today they are truly broadly utilized. There are systems based on semiconductors which can turn luminous and heat energy into electricity and vice versa. Heat and cold can be produced by some types of semiconductors. Semiconductor systems can be found in radio receiver and quantum generator, in little atomic battery and in microprocessors. Almost every worker that works in organization related to electricity ought to know how important the current sensors are. If we match devices equipped with semiconductors and tube devices we will see that semiconductors are significantly smaller and lighter. The analogue devices are not equal if we talk about their reliability and power. Tube drops behind.

From day to day we can hear about some modern inventions which assist humanity to have more conveniences or even save the lives.