SEMICONDUCTOR FABRICATION PROCESS INCLUDING RECESSED SOURCE/DRAIN REGIONS IN AN SOI WAFER

摘要

A method of forming a transistor with recessed source/drains in an silicon-on-insulator (SOI) wafer (101) includes forming isolation structures (110) in an active layer of the wafer, where the isolation structures preferably extend through the active layer to a BOX layer (104) of the wafer. An upper portion of the active layer is removed to form a transistor channel structure. A gate dielectric (120) is formed on the channel structure (143, 145) and a gate structure (140) is formed on the gate dielectric. Etching through exposed portions of the gate dielectric, channel structure, and BOX layer is performed and source/drain structures (160) are then grown epitaxially from exposed portions of the substrate bulk (102). The isolation structure and the BOX layer are both comprised primarily of silicon oxide and the thickness of the isolation structure prevents portions of the BOX layer from being etched.