On the Electrochemical Growth of a Crystalline p–n Junction From Aqueous Solutions

Our society largely relies on inorganic semiconductor devices which are, so far, fabricated using expensive and complex processes requiring ultra‐high vacuum equipment. Here we report on the possibility of growing a p–n junction taking advantage of electrochemical processes based on the use of aqueous solutions. The growth of the junction has been carried out using the Electrochemical Atomic Layer Deposition (E‐ALD) technique, which allowed to sequentially deposit two different semiconductors, CdS and Cu 2 S, on an Ag(111) substrate, in a single procedure. The growth process was monitored in situ by Surface X‐Ray Diffraction (SXRD) and resulted in the fabrication of a thin double‐layer structure with a high degree of crystallographic order and a well‐defined interface. The high‐performance electrical characteristics of the device were analysed ex‐situ and show the characteristic feature of a diode.