Reliability of MEMS Materials and Components

9820022Bhushan 本研究的目的是对选定的微电机、微开关和微齿轮系统中的配合部件表面进行详细的性能分析和微摩擦学研究，作为设备运行时间的函数，从而确定与运行期间微设备和部件故障相关的机制。长期以来，人们一直怀疑 MEMS 器件的故障是由于器件中配合表面的摩擦学特性发生剧烈变化或退化所致。将使用 AFM/FFM 研究设备运行对与配合表面相关的重要摩擦学参数（例如表面粗糙度、微观摩擦、静摩擦和机械完整性）的影响。将开发不同半径的尖端来模拟不同尺寸的粗糙接触，以研究配合表面的粘附和摩擦。通过使用纳米级开尔文探针检测磨损前兆，将研究磨损前表面结构的变化，以确定与配合表面退化相关的机制。研究测量启动电流等设备参数。将进行指示装置故障的停止电流等，并将这些数据与不同操作条件下的摩擦学参数进行比较。这将有助于了解摩擦学参数对设备故障的影响。该研究的另一个目标是确定用于 MEMS 设备的新材料、润滑剂和超薄涂层。目前使用的材料——硅和多晶硅薄膜的优惠券将与新的候选材料（例如碳化硅薄膜和其他陶瓷薄膜）进行比较。 这里的目的是寻找具有最小摩擦/静摩擦和卓越磨损性能的材料。将研究厚度范围从 10 nm 到 3.5 nm 甚至更小的超薄硬质非晶碳涂层，以确定具有最佳耐刮擦/耐磨性的最薄涂层。通过对由各种潜在抗涂层材料制成的MEMS组件进行研究，将研究其工程性能并评估其可靠性。微电机和其他MEMS器件将从制造这些器件的研究合作者处获得。通过这项研究，将更好地估计 MEMS 设备的可靠性，并显着促进对这些设备故障机制的理解。还将确定非常适合 MEMS 设备的新材料、涂层和润滑剂。因此，这项研究将对 MEMS 技术和微摩擦学科学领域互惠互利。***

9820022BhushanThe objective of the proposed research is to conduct a detailed performance analysis and microtribological study of the mating component surfaces in selected micromotors, microswitches and microgear systems as a function of operating time of the devices, thereby identifying the mechanisms associated with microdevice and component failure during operation. It has been long suspected that failure of MEMS devices occurs due to a drastic change or degradation of tribological properties of the mating surfaces in the device. The effect of device operation on the important tribological parameters associated with mating surfaces such as surface roughness, microscale friction, stiction and mechanical integrity will be studied using an AFM/FFM. Tips of different radii to simulate asperity contacts of different sizes will be developed to study the adhesion and friction of mating surfaces. By using a Nanoscale Kelvin Probe to detect precursors of wear, changes in the structure of the surfaces prior to wear will be studied in order to identify mechanisms associated with degradation of the mating surfaces. Studies to measure device parameters such as start-up current. stopping current etc., which are indicative of device failure, will be conducted and these will be compared with tribological parameters under different operating conditions. This will help to understand the effect of tribological parameters on device failure. Another objective of the study is to identify new materials, lubricants and ultra-thin coatings for use in MEMS devices. Coupons of currently used materials - silicon and polysilicon films will be compared to new candidate materials such as SiC films and other ceramic films. The aim here is to look for materials that exhibit minimum friction/stiction and superior wear performance. Ultra-thin hard amorphous carbon coatings of thicknesses ranging from 10 nm down to 3.5 nm and less will be studied in order to identify the thinnest coatings with the best scratch/wear resistance. By conducting studies on MEMS components made from various potential materials anti coatings, their engineering performance will be studied and their reliability evaluated.The micromotors and other MEMS device will be obtained from research collaborators who will fabricate the devices. Through this study, reliability of the MEMS devices will be better estimated and understanding of failure mechanisms in these devices will be significantly advanced. New materials, coatings and lubricants that are well suited for MEMS devices will also be identified. This study will therefore be of mutual benefit to the fields of both MEMS technology and microtribology science.***