Effects of Molybdate Concentration on the Characteristics of Ni–Mo–P Diffusion Barriers Grown by Nonisothermal Electroless Deposition

Abstract

Ternary Ni-based amorphous films can serve as a barrier layer for Cu interconnects in ultralarge-scale integration (ULSI) applications. In this paper, films deposited on silicon wafers without a complicated pretreatment such as Pd activation were prepared using a nonisothermal deposition (NITD) method. The deposition solutions and operating conditions for preparing the alloys are presented, and the effect of the concentration of added in electrolytes on the deposition rate is investigated. The surface morphology, microstructures, compositions, and electrical resistivity of the deposits are also thoroughly examined. Based on the experimental results, the Ni-based ternary alloys produced by the NITD method contain high levels of both Mo and P, and the properties of films are dependent on the concentration of molybdate in electrolytes. It is concluded that the thin films produced by the proposed approach in this study are promising for the technologies in ULSI.