环境湿度下硅材料表面的黏着与黏滑机理

首先采用湿法刻蚀处理硅110面，得到按一定规律排列的圆形、三角形凹坑修饰硅表面；然后在自行开发的微摩擦黏着实验机上，对光滑硅表面和凹坑修饰硅表面在湿度环境下的黏着和摩擦性能进行了测试，发现经过规则形貌修饰的硅表面可以明显地降低由于毛细作用引起的黏着．摩擦力测试中光滑硅表面在湿度超过70％后有明显的黏滑现象，而经过修饰的硅表面对黏滑有抑制作用．在此基础上，从硅表面液桥形成及断裂的角度探讨了环境湿度对黏着与黏滑的作用机理，建立了球面接触模式下不同湿度下的黏着力（pull-off force）与黏滑峰值力的计算模型与公式，并结合实验结果进一步改善了计算模型．可为控制硅袁面的毛细黏着与黏滑提供模型依据．

Pull-off Force and Stick-Slip Properties of Silicon Surface Under Environmental Humidity

Si(110) surface was modified by wet chemical etching to get regular circular and triangular texture. Then the pull-off force and stick-slip resistant performance of the smooth silicon surface and the modified silicon surface were investigated by a home-made micro-tribotester in the situations of micro load and various relative humidity levels. The results show that the modified surface can decrease the pull-off force caused by the capillary force, and also avoid the stick-slip phenomenon occurring on the smooth silicon surface when the relative humidity is over 700/0. A model based on the forming and breaking mechanism of liquid bridges was proposed to explain the principle of pull-off force and stick-slip phenomenon on bare and modified surface under environmental humidity. The model can be used to design patterns to control the capillary pull-off force and stick-slip phenomenon.