Fabrication of Sn-Se compounds on a gold electrode by electrochemical atomic layer epitaxy

The fabrication of Sn-Se compounds, at room temperature by electrochemical atomic layer epitaxy (EC-ALE) is reported. EC-ALE involves the use of surface limited reactions to form atomic layers of the elements making up a compound (Sn and Se) in a cycle. Cyclic voltammograms were used to determine approximate deposition potentials for each element. The amperometric I-t method and differential pulse anodic stripping voltammetry were used to deposit and study the processes involved in a continuous cycling deposition which were used to form thin films of the compound. Through the analysis of the I-t transients and the stripping voltammograms it is possible to establish the formation of Sn-Se compounds. Taking into account the charges involved in the I-t deposition process, a general reaction scheme that considers the formation of SnSe2, SnSe2 − x and SnSe compounds is proposed.