Characteristics of Arsenic Doped Polycrystalline Silicon-Gate Capacitors After Rapid Thermal Processing

Abstract

ABSTRACTThe feasibility and advantages of using rapid thermal annealing to achieve a proper n+ polysilicon work function are demonstrated. Our data shows that RTA can be used to activate arsenic in the polysilicon gate after a regular furnace anneal or to diffuse and activate arsenic without any prior furnace anneal. Interface states and fixed charges due to RTA can be annealed out at 500°C for 30 min in forming gas. New insights into the diffusion, segregation, and activation of As in polysilicon during furnace and/or rapid thermal annealing have been obtained.