Our group is interested in the study and growth of thin film materials. ALE is a method where atomic layers of the elements making up a compound are deposited in a cycle, using surface limited reactions. In that way, growth is always layer upon layer, with the intent of epitaxially growing high quality thin films.
Deposition is facilitated by the free energy of formation of a surface compound.
That is, a the element reacts with the substrate surface forming a compound, until the surface is covered. In electrochemical ALE, the solution is then changed and one containing a precursor to the second element is introduced. An atomic layer of the second element is then deposited on top, completing the deposition of one monolayer of the compound. Thin films are grown by repeating this cycle as many times as desired. Some work investigating growth of the III-V compounds GaAs and InAs has been pursued, as has deposition of the turnery compound CuInSe2.