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 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 confirmed the DLC characteristics of the prepared films. Water contact angle increased from <30° on
oxide-coated surfaces, to >110° 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 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 technology. The beam arrays were
checked with scanning electron microscope. When the DLC films presented, the average longest detachment length was
approximately 145 &mgr;m. While the DLC films didn't present, the average critical detachment length was shorter than
80..m. These results indicated the stiction of polysilicon cantilever beams was effectively restrained with DLC coatings.
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