Study On Some Key Technologies Of MOEMS-based Grating Moving Light Modulator Array

Nowadays, the light modulators based on Micro-Opto-Electro-Mechanical Systems (MOEMS) have been developed fast and applied widely in the market of display due to their merits. Being the key device of display equipment, MOEMS-based light modulator becomes an important branch which promotes the display industry. MOEMS-based light modulator has become one of the research focuses. The research of this technology has great value and prospective application.After careful comparison and analysis of the most famous MOEMS-based light modulators, a novel MOEMS-based light modulator for display was proposed, which is called Grating Moving Light Modulator (GMLM). In this paper, the key technologies of design, fabrication and test of the device were summarized, and the operation principal was verified correct on the principal projection demo system.Details of this paper are listed as follow:①After summarizing the review of literature about MEMS-based light modulator of home and abroad, a novel MEMS-based light modulator named GMLM was proposed.②The operation principal of GMLM was analyzed. The static and dynamic instincts were analyzed using the electro-mechanical model. Especially, the modified parallel-plates-capacitance equation was deduced. In additional to these works, the spring constant, pull-in voltage, operation voltage, natural frequency, switch time and squeeze-film air damp coefficient were deduced.③The structure parameters of GMLM were designed and verified by FEM simulations. The control system based on FPGA and drive system were designed.④The fabrication process was proposed by analysis fabrication processes of main MOEMS-based light modulators. The key problems in three fabrications were studied, such as release process, stiction and buckling under stress. At last, a process based on the Al film was formed, which is helpful to research of future MOEMS device.⑤The test methods were investigated. The surface qualities such as reflectivity, roughness and profile were measured. The static and dynamic parameters mentioned above were measured on the electro-mechanical test system. Finally, the static and dynamic projection results of GMLM array were achieved by the projection demo system, which verified the operation and projection principals of GMLM. ⑥The hysteresis-based passive matrix address method and active matrix address methods were given to solve the crosstalk problem of the GMLM array. And monolithic integration which combines GMLM and CMOS circuits was proposed. In additional to all of these work, the main failure modes of GMLM were studied and the improve methods were given.At last, the work and innovation points were summarized.