Electrocrystallization and electrodeposition of silver on titanium nitride

Abstract

The electrocrystallization and electrodeposition of silver on TiN substrates in AgNO₃ + KSCN solutions were studied by electrochemical methods and scanning electron microscopy. The description of Ag electrocrystallization is given in terms of instantaneous, progressive or mixed nucleation models. The parameters of electrocrystallization were determined and the fractional area covered by silver was estimated. A two-step procedure was used for forming a continuous silver film on a TiN substrate. During the first step, a seed layer was deposited on TiN by applying either high negative potential or cathodic current density in 0.011 M AgNO₃ + 2.5 M KSCN solution. The applied cathodic current density was higher than the limiting diffusion current in the solution. During the second step, a bulk silver film was deposited galvanostatically from a 0.22 M AgNO₃ + 2.5 M KSCN solution at a cathodic current density lower than the limiting current density.