Quasi-conductors are believed to be a unique kind of chemical elements. This type was researched in early 1980's but there were no required technologies to carry on the further researches. The research of semiconductors was continued just in the 1920's. The first successful experiment was carried out by the Russian scientists in 1923. They proved that semiconductors may be used to generate fluctuations. There was no possibility to create some unique devices as igbt modules. The most significant event in the history of semiconductor devices was the creation of the first transistor by Bell company in 1949. Since then many people all over the world become interested in such kind of matter as semiconductors.

The interest to optical features of semiconductors revived due to research of induced emission in semiconductors. By usage of such principles as p - n barriers and heterojunction scientists managed to design laser device in the beginning of the 60's.

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