Research On The Major Problems Of The Analysis And Evaluation Of Functional Characteristics Of Microstructures Of MEMS

With the rapid development of MEMS technology, the quality control of MEMS is considered as an important issue. And a key procedure of it is the measurement and analysis and evaluation of microstructures of MEMS.Recently, the devices like white-light vertical scanning interference microscope are utilized for the high-precision measurement of the microstructures of MEMS. However, the analysis and evaluation of functional characteristics of microstructures of MEMS are the problems to be solved for the quality control of MEMS, such as:With the improvement of processing precision and the enlargement of the entire size of microstructures, it is hardly to obtain complete information of MEMS by one time microscopic imaging, which limits the analysis and evaluation of functional characteristics of microstructures of MEMS; Most of Assessment Parameters of Areal Surface Texture defined by the International Organization for Standardization(ISO) in ISO25178 can not describe the Function and Character of microstructures of MEMS, the parameters that describe the Function and Character of microstructures of MEMS are need urgently for the quality control of MEMS;Defects of microstructures of MEMS influence the quality of MEMS and the method of manual inspection could not meet the demands of defects inpection of microstructures of MEMS in mass production, to realize the automatic inspection and classification of defects of microstructures of MEMS is needed.To solve the problems above, the research is carried out in this dissertation, and the main outlines and innovations of this dissertation are as follows:The method for the automatically 3D mosaic of MEMS applied to white-light vertical scanning interference microscope is proposed to obtain the microscopic image of microstructures of MEMS that contains complete information of MEMS with large field and high resolution to meet the demand of the analysis and evaluation of functional characteristics of microstructures of MEMS. This method doesn't need the strict alignment. The problem of the automatically mosaic of microstructures of MEMS with arbitrary shape with high precision is solved. An improved Hough tranform(Ht) based on the Sub Peak Tracker(SPT) is proposed to solve the problems that orientation detections are vulnerable to tiny orientation change of the oriented microstructures and lead to loss some information in most existing Hts, and it is utilized to extract the orientation of microstructures in the microscopic image of microstructures efficiently and robustly. According to the orientation of microstructures, typical parameters of the function and character of microstructures of MEMS which affect the quality of microstructures, sush as the width and Aspect Ratio(AR) of micro-step/micro-trench, the parallelism,perpendicularity and angle between micro-trenches/micro-steps, are evaluated. Experimental result shows the proposed method is robust and accurate.A method for the automatic inspection,classification and evaluation of the typical defects of microstructures of MEMS based on Influence Region Template(IRT) is proposed. The IRT is built via the Reference microscopic image of microstructures, then the Test microscopic image of microstructures is compared with the IRT to obtain the location, classification and the evaluation of 3D size of defects of microstructures. The defects of microstructures of MEMS which affect the quality of microstructures but can not evaluated by parameters of the function and character of microstructures are located and classified, the 3D size of defects of microstructures are evaluated, the rate of false alarm induced by the alignment error and tiny deformation of microstructures is reduced.The experiments of the analysis and evaluation of functional characteristics of microstructures of MEMS are carried out, and the effective verification is obtained.