Patent ID: 6294464
Filing Date: 2001-09-25
Classification: H01L

Abstract:
A process of forming a local interconnect comprising:providing at least one semiconductor layer;forming a layer of titanium over said at least one semiconductor layer, said layer of titanium having a thickness ranging from about 200 Angstroms to about 600 Angstroms;forming a mask layer of tungsten silicide over said layer of titanium, said mask layer of tungsten silicide having a thickness ranging from about 500 Angstroms to about 1200 Angstroms;selectively etching said mask layer to define a boundary of said local interconnect;annealing said mask layer and said layer of titanium in an atmosphere of reactive nitrogen thereby forming a composite structure where said mask layer contacts said layer of titanium and nitrifying at least said layer of titanium not covered by said mask layer to form a layer of titanium nitride, said composite structure comprising titanium silicide, tungsten silicide and a titanium tungsten intermetallic compound; andremoving said layer of titanium nitride and underlying titanium to form said local interconnect.