Chalcogens poly chalcogen cation

One of the simplest techniques used to electrodeposit semiconductors is cathodic deposition from nonaqueous solutions containing elemental chalcogen (S, Se) and a metal salt, first described by Baranski and Fawcett [17]. Two main mechanisms have been considered deposition of metal (e.g. Cd) followed by chemical reaction with elemental chalcogen in solution and reduction of chalcogen to (poly)chalcogenide followed by ionic reaction between chalco-genide and metal cations. Which mechanism will dominate depends on the specific system (substrate, semiconductor, deposition conditions) and may change in the same deposition. 

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