Patent ID: 6107195
Filing Date: 2000-08-22
Classification: H01L

Abstract:
A process of forming an interconnect stack comprising first a Titanium (Ti) layer, followed by a titanium oxynitride barrier (TiON) layer, and finally an aluminum (Al) layer, such that the specific formation process of the titanium oxynitride results in a low resistivity of said layer and provides for a good crystalline texture of the subsequently deposited Al, the process comprising:providing a substrate having contacts/vias thereon;sputter depositing a first conductive layer of Ti on the surface of the substrate in a vacuum deposition apparatus;forming a second conductive barrier layer of TiON upon the Ti without removing the substrate from the vacuum deposition apparatus by sputtering Ti in an argon, nitrogen, and oxygen atmosphere where the nitrogen to oxygen ratio is in the range of 15:1 to at least 25:1 at substrate temperature of at least about 300.degree. C.; andsputter depositing an Al layer upon the TiON layer in the vacuum deposition apparatus,wherein there is substantially no oxygen found at the interface between the Al layer and the second conductive barrier layer of TiON.