Study of an Elevated Drain Fabrication Method for Ultra-Shallow Junction

An elevated diffusion layer fabricated from polycrystalline silicon (poly-Si) by solid phase diffusion was investigated in detail by secondary-ion mass spectroscopy (SIMS) analysis. We clarified that it was necessary to control the native oxide in the poly-Si/Si substrate interface and use small-grained poly-Si to fabricate uniform and controllable shallow junctions. The low-capacitance sidewall-elevated drain (LCSED) metal oxide semiconductor field-effect transistor (MOSFET) fabricated by the oxygen-free load-lock low-pressure chemical vapor deposition (LPCVD) poly-Si (L/L poly-Si) was extremely effective for marked scaling down of transistor size and realizing an ultra low reversed junction leakage current.