Nickel alloy sputtering target

Abstract

A nickel alloy sputtering target containing 0.5 to 10 at % of tantalum in nickel, in which inevitable impurities excluding gas components are 100 wtppm or less. Provided is a nickel alloy sputtering target, and the manufacturing technology thereof, enabling the formation of a thermally stable silicide (NiSi) film, unlikely to cause the coagulation of films or excessive formation of silicides, having few generation of particles upon forming the sputtered film, having favorable uniformity and superior in the plastic workability to the target, and which is particularly effective for the manufacture of a gate electrode material (thin film).

Description

TECHNICAL FIELD [0001] The present invention relates to a nickel alloy sputtering target enabling the formation of a thermally stable silicide (NiSi) film, having favorable plastic workability to the target, and which is particularly effective in the manufacture of a gate electrode material (thin film), as well as to the manufacturing method thereof. BACKGROUND ART [0002] In recent years, the use of NiSi film in the salicide process as the gate electrode material is attracting attention. Nickel, in comparison to cobalt, is characterized in that it is capable of forming a silicide film with less consumption of silicon during the salicide process. Further, NiSi, as with a cobalt silicide film, is characterized in that the increase of fine wire resistance pursuant to the miniaturization of wiring is unlikely to occur. [0003] In light of the above, nickel is being used instead of the expensive cobalt as the gate electrode material. [0004] Nevertheless, in the case of NiSi, it can easily...

AI Technical Summary

Benefits of technology

The present invention provides a nickel alloy sputtering target that can form a thermally stable silicide film with minimal coagulation of films and particles, and favorable uniformity and plastic workability. The target contains specific metal elements such as tantalum, which can be added to high purity nickel to achieve these technical effects. The target also has low impurity levels, including oxygen, nitrogen, hydrogen, and carbon, and has a high initial magnetic permeability and favorable crystal grain size. The manufacturing method involves final heat treatment at a recrystallization temperature of up to 950° C.

Problems solved by technology

Nevertheless, in the case of NiSi, it can easily make a phase transition to the more stable NiSi2, and there is a problem of the boundary roughness becoming aggravated and highly resistive.

Moreover, there are other problems in that the film is easily coagulated and excessive formation of suicides may occur.

Further, with conventional technology, problems have been indicated in that NiSi is easily oxidized even within the silicide material, large irregularities are formed on the boundary area of the NiSi film and Si substrate, and a connection leak will occur.

Nevertheless, since the nitride film on the NiSi formed by accumulating TiN on Ni is thin, there is a problem in that it is difficult to maintain the barrier properties for a long period of time.

Further, the heat resistance properties are inferior to a titanium silicide film, and problems have been indicated in that the heat upon accumulating the silicon oxide film as the interlayer film after the completion of the salicide process causes the coagulation of the cobalt disilicide (CoSi2) film and the resistance to increase (c.f.

As a result of manufacturing a nickel alloy target based on this kind of conventional nickel, plastic workability was inferior and it was not possible to manufacture a high quality target.

Also, there was a problem in that numerous particles were generated during sputtering, and the uniformity was inferior.