Method of forming electrodes of semiconductor device

Abstract

A method for forming electrodes with strong adhesion strength for a semiconductor device is provided. The adhesion strength between a Si substrate and a Ti film is made higher than the pulling stress of a Ni film. Before an electrode is formed using sputtering process, the natural oxide film grown on a semiconductor substrate is removed using an Ar reverse sputtering while the top surface of the silicon substrate is converted to an amorphous through a bombardment and introduction of Ar. While Ti is deposited, a Si-Ti amorphous layer is formed in the Si/Ti interface. In this case, the amount of Ar atoms is controlled less than 4.0.times.10.sup.14 atoms/cm.sup.2. The Ar amount also can be controlled by adjusting the conditions such as the output or cathodic voltage of Ar reverse sputtering and decreasing the absolute value of Ar in the amorphous Si layer. Also the Ar amount can be controlled by diffusing Ar atoms into the substrate at more than about 300.degree. C. during Ti film deposition to diverse the Ar distribution. As a result argon atoms which concentrates at the interface do not affect with respect to the Si-Ti amorphous layer, whereby the bonding strength of the amorphous layer is maintained. Therefore, the strong adhesion strength between Si and Ti can provide a sufficient durability against the film stress of the Ni film.