DLC Films as Anti-stiction Coatings for MEMS

摘要

The stiction of microstructures is still a challenging problem in spite of innovative advances in modern micromachining technology. In this paper, diamond-like carbon films roblem were suggested as a solution for this problem. The microwave electron cyclotron resonance plasma enhanced CVD equipment has been applied to prepare the DLC films. Confocal Raman spectra confir ere confirmed the DLC characteristics of the prepared films. Water contact angle increased from <30o on oxide-coated surfaces, to >110o on DLC-coated surfaces. The adhesion force of the DLC films was as low as 3.8nN measured by AFM, whereas the adhesion force of the oxide-coated ed surface surfaces was approximately 11.2nN. The polysilicon cantilever beam arrays have been used to determine the success of DLC coating for releasing microstructures. DLC films were prepared under the polysilicon cantilever beams with the sacrificial etching technolog s technology. The beam arra. arrays were checked wit s with scanning electron microscope. When the DLC fil films presented, the average longest detachment length was approximatel s approximately 145 m. While the DLC fil films didn't present, the average critical detachment length was shorter than 80 m. These results indicated the stiction of polysilicon cantilever beams was s effectively restrained with DLC coatings.