Inventors:
Norman Godinho - Los Altos Hills CA
Frank T. Lee - Monte Sereno CA
Richard F. Motta - Los Altos CA
Joseph Tzou - Belmont CA
Jai-man Baik - San Jose CA
Assignee:
Paradigm Technology, Inc. - San Jose CA
International Classification:
H01L 21283
H01L 2188
Abstract:
An MOS transistor for use in an integrated circuit, particularly CMOS integrated circuits, is fabricated with a self-aligning contact and interconnect structure which allows for higher packing density. Self-aligning source and drain contacts overlap the gate but are prevented from short circuiting to the gate by oxide insulation between source/drain contacts and the gate, and a layer of silicon nitride above the gate. Contacts to the gate are made on top of the gate over the active region of the transistor because the source and drain regions are protected by a hardened layer of photoresist during etching of insulation to expose the gate contact. Source, drain and gate contacts are protected by a layer of titanium silicide so that interconnects are not required to completely cover these areas. Low resistance interconnects are formed of titanium silicide encapsulated by a thin film of titanium nitride.