Modification on surface roughness has been shown effectively to alleviate both release and in-use stiction in the previous literatures. However, the modified materials in the previously reported methods were limited to polysilicon or single crystalline silicon with special properties. Here, the proposed modification method not only can apply to silicon without extra property requirements, but also has potential to modify other materials, such as oxide, nitride, and some metals. The process combined spin-on photoresist and reactive ion etching (RIE). The proposed low temperature process is simple, and no extra mask is needed. Consequently, there is more flexibility to add the roughness modification to the original fabrication process of micro devices. In this study, polysilicon and silicon nitride are demonstrated as the modified materials. Then the anti-stiction effect is characterized by calibrating the detachment lengths of released cantilevers and water contact angle on the modified surface. The experimental results show that the detachment length is almost twice longer than the cantilevers without modified substrate, where the interfacial surface energy between solids is reduced about fifteen times. Besides, polysilicon with a nearly hydrophobic surface is obtained after the modification process.

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