14 - Sb Pile-up at the SiO2/Si Interface during Drive-in Process after Predeposition using SOG Source

Abstract

Antimony (Sb) is promising as dopant for shallow junction formation in scaled down devices because of its low diffusivity. Recently, 0.1 μm Metal-Oxide Semiconductor Field Effect Transistor (MOSFETs) with ultra-shallow source and drain extensions fabricated by Sb implantation have been reported. In another report, it has been described that pile-up of Sb at the SiO2/Si interface results in dopant loss during the solid phase epitaxial growth of amorphized layer formed by the implantation. However, the fundamental data of Sb diffusion are shorter than other dopants. In addition, many annealing steps in the Large-Scale Integrated (LSI) circuit fabrication process and reactions at Si surface have great influences on shallow junction formation. Therefore it is necessary to collect and analyze fundamental data of Sb diffusion for accurate diffusion modeling. This chapter presents a study, the aim of which is to clarify the Sb pile-up phenomenon during a drive-in process after pre-deposition using a diffusion source and to measure the diffusion coefficient of Sb in Si.