Topic of this thesis is performance of semiconductors and their application. Semiconductors are chemical compounds that are created naturally or atificially, and we can find them in nature. In electronics they are mostly used because of their ability to act like isolators or conductors. Their structure allows passage of unpaired electrons so that they can act like isolators or conductors. Semiconductors have better electrical conductivity than isolators and worse electrical conductivity than conductor. Semicoductors are mostly in crystal cubic composition. There is three different structures in crystal cubic composition: primitive cubic cell, plane centered cubic cell and volume centered cubic cell. Atoms form covalent bonds in semiconductors which are weaker from ones that we can find in insulators. Between valence and conduction band is a band gap with value of 3eV. Semicoductors can be divided intro intrinsic semiconductors and extrinsic semiconductros. Intrinsic semicondutor is pure semiconductor which is not doped with any dopands. Extrinsic semiconductor is doped semiconductor. During the production of a semiconductor, dopand is doped in a semiconductors crystal lattice through chemical process. That is done so there could be a semiconductor wtih different characteristics than an intrinsic semiconductor. Doping of an semiconductor is process in which intrinsic semiconductor become extrinsic semiconductor. During the doping, atoms of dopand are doped into intrinsic semiconductor. Atoms of dopand are atoms of an different element than the instrinsic semiconductor. Semiconductors could also be divided in p type semicondutor and n type semiconductor. N type semiconductor has got more electrons than holes, because it is doped with dopands which gives n type semiconductor electrons. P type semiconductor has got more holes than electrons, and it is doped with dopand which gives p type semiconductor holes. P N junction is the boundery between p type and n type semiconductor in a single semiconductor crystal. Almost every electronic device contain semicondutors, and thats because every integrated circuit contain semiconductor, and every laptop, mobile phone, scanner, etc. contain intagreted circuit. Their wide application indicates increasing investment in research of this material and increasing use of semiconductors in the future. All properties and applications of semiconductors in devices will be discussed further in this thesis.