Fabrication of Shallow Junctions with Conventional Furnace Equipment by Using Silicon Preimplants

Abstract

ABSTRACTThe global scaling down of device dimensions requires process technologies which are able to create ultra-shallow junctions. Besides using ultra-low implant energies for shallow junction creation we present an alternative approach for the creation of MDD (Medium Doped Drain) junctions by using moderately low implant energies. Our approach employs the dopant/point-defect interaction mechanism to retard dopant diffusion as well as dopant de-activation in the tail of the diffusion profiles to achieve suitable shallow junctions. The silicon preimplant allows fabrication of 90nm arsenic, 150nm phosphorus, and 140nm boron metallurgical junctions for a 40keV arsenic, 20keV phosphorus, and 8keV boron implant.