Patent ID: 6203674
Filing Date: 2001-03-20
Classification: C23C,H01L

Abstract:
A method of continuously forming a Ti/TiN film by sputtering from a common target onto a substrate disposed in a pressurizable process chamber in communication with a source of N.sub.2, the method comprising the following steps:a) sputtering a Ti film onto the substrate;b) introducing a flow rate of N.sub.2 gas in the chamber and increasing a pressure in the chamber to greater than about 4.0 mTorr while applying no sputtering power;c) controlling the flow rate of N.sub.2 gas and the pressure in the chamber to define a first branch of a hysteresis by reducing the flow rate of N.sub.2 gas in the chamber and reducing the pressure in the chamber through a range from about 4.0 mTorr to about 2.5 mTorr and applying sputtering power to sputter a nitride mode TiN film on the target;d) reducing the flow rate of N.sub.2 gas and decreasing the pressure to less than 2.5 mTorr;e) controlling the flow rate of N.sub.2 gas and the pressure in the chamber to define a second branch of the hysteresis by increasing the flow rate of N.sub.2 gas and increasing the pressure through a range from about 2.5 mTorr to about 4 mTorr and applying sputtering power to sputter a metallic mode TiN film on the target;wherein the first branch of the hysteresis follows a path that is at a higher pressure than a path for the second branch of the hysteresis.