Elimination of post-release adhesion in microstructures using thin conformal fluorocarbon films

The adhesion of polysilicon microstructures to their substrates is eliminated using a thin coating of a hydrophobic fluorocarbon film. The film is grown in a plasma reactor in a field-free zone yielding a relatively conformal film growth. Experiments confirm the presence of the film on the surfaces of 100 /spl mu/m undercuts with contact angles of 110/spl deg/. The film eliminates the adhesion of polysilicon beams up to 230 /spl mu/m-long even after direct immersion in water. Initial accelerated aging tests indicate that the film withstands temperatures up to 400/spl deg/C. Wear test show the film remains effective after 10/sup 8/ contact cycles.