Electronical Extraction Of MEMS Geometric And Electronic PCM Parameters

Micro-electro-mechanical system (MEMS) is a new area which spring up a research upsurge in the internationality in recent years. MEMS is a neither technology revolution. At the present time, the application of MEMS is slower than that expected although the investments of every country are increasing every year. The main reason is that the reliability of MEMS product can not be ensured. A lot of MEMS product are now still in the laboratory except a few products have become merchandise.The surface manufacturing process of MEMS started from 1980s. This kind of process avoids a lot of shortcomings of body manufacturing process of MEMS. Its process steps are more mature and it's easier integrated with IC manufacturing process. Because of these advantages, it became one of the most popular MEMS manufacturing processes. Process-control-monitor (PCM) system is the most effective means to improve the reliability of products and the producing efficiency. So it is very important to establish a PCM system for MEMS surface manufacturing process.An entire PCM system of MEMS surface manufacturing process should include three parts: electronic parameters extraction, geometric parameters extraction and material property parameters extraction. What studied in this paper is the electrical extraction of those electronic and geometric parameters which affect the performance mainly.First, the origin of MEMS, together with the conception, the characteristics and the application foreground of MEMS are illustrated separately in this dissertation. The surface manufacturing process of MEMS and the electronic and geometric parameters which need to measure have been described in detail. Because of the particularity about MEMS PCM extraction, three traditional optical and mechanical techniques for measuring layer thickness are introduced. After introduced the Van Der Pauw theory, one sheet resistance test structure which fits the need of MEMS surface process is offered by this paper. This structure can be used for poly1, poly2 and metal sheet resistance measurement. In this dissertation, one contact resistance test structure for surface process is mentioned after described the theory of contact resistance from metal to semiconductor.Anchor area is a special layer which used at MEMS surface manufacturing process only. The misalignment of this layer affects the performance of MEMS device strongly. To monitor this kind of misalignment, a electrically test structure is offered. And this structure can be used for measurement of poly2 to metal alignment. Later, one set of line width test structure is introduced for poly1, poly2 and metal line width measurement, which is optimized for MEMS surface process.