METHOD FOR FABRICATING SILICON-ON-INSULATOR TRANSISTOR WITH SELF-ALIGNED BORDERLESS SOURCE/DRAIN CONTACTS

摘要

A method is provided for fabricating a transistor. A replacement gate stack is formed on a semiconductor layer, a gate spacer is formed, and a dielectric layer is formed. The dummy gate stack is removed to form a cavity. A gate dielectric and a work function metal layer are formed in the cavity. The cavity is filled with a gate conductor. One and only one of the gate conductor and the work function metal layer are selectively recessed. An oxide film is formed in the recess such that its upper surface is co-planar with the upper surface of the dielectric layer. The oxide film is used to selectively grow an oxide cap. An interlayer dielectric is formed and etched to form a cavity for a source/drain contact. A source/drain contact is formed in the contact cavity, with a portion of the source/drain contact being located directly on the oxide cap.