In this paper we report on the electrodeposition process from a highly acid
ic aqueous sulphate electrolyte and discuss the relationships between elect
rochemical kinetics and crystalline structure of the electrodeposits. The e
lectrochemical kinetics were studied by voltammetric and potentiostatic met
hods, showing the peculiarities of the cathodic process of highly acidic ba
ths, leading - under suitable plating conditions - to the removal of the Te
excess which is typical for the ZnTe electrodeposition systems reported in
the literature. Potential transient techniques and scanning electron micro
scopy (SEM) imaging were used to study the nucleation. They showed that the
nucleation process is instantaneous. The crystalline structure of the depo
sits was studied by X-ray diffraction (XRD), revealing the possibility of g
rowing directly cubic ZnTe films under suitable electrochemical conditions.
A minor amount of Te can form at the surface as a result of etching by the
electrodeposition bath. Structural data were complemented by X-ray photoel
ectron spectroscopy (XPS) analyses and compositional measurements by energy
dispersive spectrometry (EDS). (C) 2000 Elsevier Science S.A. All rights r
eserved.