Semiconductors are the detached class of matters. In the first time that unique type was found in the 1890's but more thoroughly it began to be researched just after the First World War in Europe and in Soviet Union. The first successful experiment was carried out by the Russian physicists in 1923. They proved that semiconductors can be utilized to generate fluctuations. There was no possibility to develop some unique devices as diodes. Just in the beginning of the 60's with the invention of transistors in 1949 the wide use of crystal detectors started. The intense studying of the characteristics of semiconductors was started at the same time.



A lot of physicists carry out a great deal of researches just to get more knowledge about such characteristic of semiconductors as stimulated emission. It led to the creation of semiconductor laser system based on usage of p ? n barriers and then on heterojunction.

Nowadays we can see a great deal of different pulsed power devices which operate with assistance of usage of semiconductors. If there were no semiconductor devices used in the newest technologies, we won't have an opportunity to carry out such nice researches that are important for other sciences.

Semiconductors are a broad kind of substances that are characterized by the value of conductivity which is situated between the conductivities of metals and isolators. There are some substances that are mainly used to create the semiconductor devices. They are germanium, selenium, silicon, etc.

It sounds a bit strange but scientists didn't want to perform experiments of semiconductors for a long time. The first man that decided to gain more knowledge about semiconductors was Abram Ioffe ? Russian scientist. He found that semiconductors are the special class of crystals with some definite features. Every semiconductor device has such main features as electron and hole conduction. It is dependant on the chemical composition of the introduced admixtures. To get the features that are required for the experiment or proper usage of device some admixtures are added to semiconductors.

Almost every sphere of modern technologies implies use of semiconductors. Diodes, transistors and thyristors are the most often used devices. The wide application of semiconductors began not so long ago but today they are really widely utilized. There are systems based on semiconductors that may convert light and heat energy into electricity and vice versa. Heat and cold may be developed by some kinds of semiconductors. Semiconductors perform the main functions in lots of various devices: atomic batteries, quantum generators, processors and even primitive radio receivers. Workers can't do without semiconductor rectifiers, changers, current sensors and amplifiers. The weight and overall dimensions of semiconductor devices are significantly smaller than their tube variants. The analogue devices are not equal in case we speak about their reliability and power. Tube drops behind.

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