Resistivities of Thin Film Transition Metal Silicides

Abstract
Resistivities of the transition metal silicides have been determined. The silicides were formed either by reacting thin metal films with silicon or polysilicon substrates or by sintering cosputtered (metal + silicon) films on silicon, polysilicon, or oxide substrates. The sheet resistance of the film was determined as a function of the sintering temperature, in the range of 300°–1100°C. At the same time, the intermetallic compound formation due to sintering at different temperatures was investigated by the use of x‐ray diffraction technique. It was found that the initial interaction between the metallic film and the substrate was slower for polysilicon substrates compared to silicon substrates; the end product, however, was identical. The resistivity of the refactory metal silicides was lowest for the disilicide and increased with increasing atomic number in a given period of the periodic table. The spread in the resistivities of the 4th period silicides was found to be larger than that of the 6th period silicides. Similarities with the borides, carbides, and nitrides of the same metals are pointed out. On the other hand, for VIII group metal silicides, resistivities were low and no correlation was observed.