Preparation of Tribological Materials for Microelectromechanical systems

(1)硅单晶的微摩擦学性能和磨损结构硅单晶的微摩擦学性能是影响MEMS实用化的重要因素之一。本研究主要研究了晶体取向对硅单晶微磨损的影响及其磨损结构。采用原子力/摩擦力显微镜（AFM/FFM）进行微摩擦实验，研究晶体取向对硅单晶微磨损深度的影响。在这些实验中，AFM/FFM尖端的扫描-划痕方向在Si（100）表面为<100>和<110>，在Si（111）表面为<112>。结果发现，硅表面产生的磨损痕深度依次增大：<112>,<100>,<100>。对微磨损痕迹进行了透射电镜观察。结果发现，在初始阶段，在表面区域产生了小的位错环，微磨损增多，并且随着微磨损的进行，位错的尺寸和数量增加。(2) zr基金属玻璃及其复合材料的摩擦学性能采用电弧熔炼和铸造法制备了ZrC粉增强zr基金属玻璃及其复合材料。利用销盘式磨损试验机对所制备材料的摩擦学性能进行了研究。结果发现，zr基金属玻璃及其复合材料的耐磨性优于常规铝合金A4032（Lowex）。锆基金属玻璃复合材料增强15vol。ZrC粉末在试验材料中表现出良好的耐磨性和较低的摩擦系数。用透射电镜观察了磨损痕迹表面的显微组织。结果表明，经过磨损试验，zr基金属玻璃的非晶态相得到了保留。(3)离子束辅助沉积法制备氮化碳薄膜的力学性能采用离子束辅助沉积的方法在Si（001）衬底上制备了氮化碳（CN）薄膜。碳被电子束蒸发，氮和氩离子同时从一个离子源轰击。在Ar/N2比为1时制备的膜具有较高的硬度和良好的耐磨性。少

(1) Microtribological properties of silicon single crystal and the wear structureMicrotribology of silicon single crystals is one of the important factors for the practical use of MEMS. In this study, the effect of crystal orientation on microwear of silicon single crystal and the wear structure were mainly investigated. Microfriction experiments using atomic force/friction force microscope (AFM/FFM) were carried out to investigate the effect of crystal orientation on the microwear depth of Silicon single crystals. In these experiments, the scanning-scratching directions of a tip of AFM/FFM were <100> and <110> on Si(100) surface and <112> on Si(111) surface. As a result, it was found that the depth of the wear marks generated on silicon surfaces increased in the following order : <112>, <100>, <100>. Cross-sectional TEM observations of the microwear marks were carried out. As a result, it was found that the small dislocation loops were generated in the surface region at the first stag … More e of the microwear, and the size and the number of dislocations increased with the progress of the microwear.(2) Tribological properties of Zr-based metallic glass and its compositesZr-based metallic glass and its composites reinforced with ZrC powder were prepared by arc-melting and casting. The tribological properties of the materials thus prepared were investigated by using pin-on-disk type wear testing machine. As a result, it was found that the wear resistance of Zr-based metallic glass and its composites was better than that of conventional aluminum alloy A4032(Lowex). Zr-based metallic glass composite reinforced with 15vol.% ZrC powder exhibited a good wear resistance and low friction coefficient among the materials tested in this study. The microstructure of the surface of of the wear traces was observed by TEM. As a result, it was found that amorphous phase of Zr-based metallic glass was preserved after the wear tests.(3) Mechanical properties of CN films prepared by ion-beam-assisted depositionCarbon nitride (CN) films were prepared on Si(001) substrates by ion-beam-assisted deposition. Carbon was evaporated by electron beam and N and Ar ions bombarded simultaneously from one ion source. The films prepared under Ar/N2 ratio of 1 exhibited high hardness and good wear resistance. Less