A reforming technique with ion implantation for polysilicon microstructures

We have found that deflected polysilicon beams can be reformed by ion implantation. Under ordinary ion implantation conditions at the IC process the deflection of 1.88 /spl mu/m at the tip of a polysilicon cantilever beam with a thickness of 2.1 /spl mu/m and length of 200 /spl mu/m was reduced to almost 0. The reforming amount can be controlled by dose, acceleration voltage and mass of the implanted ions. The cause of reforming the deflection is the compressive stress in the polysilicon beam, generated by ion implantation, and this stress makes the beam warp in an opposite direction for the deflection. It should be assumed that the amorphous state formed by ion implantation is related to the generation of compressive stress.