Student Consulting Association

Posted: High Technologies

The material for semiconductors generally has the electrical resistance among the resistance of a conductor and a non-conductor. The resistance of semiconductors also is affected by variations of temperature or used admixtures.

The material includes impurities if some other elements have been mixed to it. Semiconductors are labeled as semiconductor assembly of type-n or type-t depending on the kind of finished material.

The union of type-n and type-t semi-conductors is applied to make diodes and transistors. Generally silicon is necessary to produce semiconductors now.

Semi-conductor substance is used to get diodes that serve for letting the stream of electrical current only in one sense. In every single diode there is a component made of positive and negative elements (p- and n-) and of barrier level (pn-transfer). Electrical schemes that change among alternating and direct current are made applying diodes. Just a part of the period or cycle is to be completed as diodes let current flow only in one sense. They call such a junction a rectifier.

Speaking of the light diodes that figure as LED, they are necessary to produce light at low voltages not creating heat. In computers, cameras and mobile phones, different equipment these days one can see light diodes as those diodes are applied to show the idle mode.

The development of thyristors production was governed by Moore's law. What is the most significant side to make complicated power semiconductor equipment at lower cost? That's lithography. Concerning optical lithography, it now leads to the popularization of alternate techniques as it has met its development limit. Admittedly ultraviolet lithography and nano-imprint lithography are to become the successors to optical lithography. (more…)

Posted: Progress & Technology

There is a detached class of substances which is named quasi-conductors. In the first time this unique type was found in the 1890's but more completely it started to be researched only after the First World War in Europe and in Soviet Union. In 1923 Russian scientists proved the ability of usage of semiconductor-metal contacts to accelerate the producing of fluctuations. There was no possibility to develop some unique devices as semiconductor assembly. Just in the beginning of the 50's with the appearing of transistors in 1949 the broad usage of crystal detectors started. Since then many persons all over the world become interested in such kind of substance as semiconductors.

Stimulated emission is actually a very interesting feature of semiconductors that has been researched for several tens of years. First laser system was developed with usage of semiconductors. The first variant was based on p - n barriers, the latest ones - on heterojunction.

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