Ultrashallow junction formation by rapid thermal annealing of arsenic-adsorbed layer

Ultrashallow junction formation in sub-0.1 mu m metal oxide semiconductor f ield effect transistor (MOSFET) fabrication has been focused on as a key pr ocess technology. In this work, the arsenic (As) doping method, with rapid thermal annealing of the As-adsorbed layer with a capping oxide: was invest igated for the first time as a technique for shallow junction formation. Th e As-adsorbed layer is successfully fabricated by AsH3 injection into the g as-source molecular beam epitaxy (GSMBE) apparatus. As-layer doping provide s an extremely shallow junction (X-j: 20 nm) with a low sheet resistance (b elow 2 k Ohm/sq.), thus proving to be a superior technique for shallow junc tion formation in the source/drain extension region of N-channel MOSFETs.