Electrodeposition and characterization of undoped and nitrogen-doped ZnSe films

Semiconducting films of (n-type) ZnSe and (p-type) nitrogen-doped ZnSe were electrodeposited by a linear-sweep voltammetric technique on to a substrate of fluorine–tin oxide (FTO) glass ceramics. The films were characterized by scanning electron microscopy, energy-dispersive X-ray analysis and grazing-incidence X-ray diffraction. The results indicated that the material was deposited uniformly over the substrate, forming clusters when the Zn content of the bath was 0.1 mol L−1 and a film when it was 0.2 or 0.3 mol L−1. The effectiveness of doping the films with nitrogen by adding ammonium sulfate to the deposition solution was assessed by measuring the film–electrolyte interface capacitance (C) at various applied potentials (Eap) and plotting Mott–Schottky curves (C−2 vs Eap), whose slope sign was used to identify p-type ZnSe.