Study On Moems-based Grating Light Modulator For Micro-Spectrometer

MOEMS (Micro-Opto-Electro-Mechanical Systemsis) is an important research area of MEMS technology which has the advantages of low cost, high integrated and reliable. MOEMS-based micro spectrometer has become one of the main development trend in the field of spectroscopy. In this thesis, the technologies of micro spectroscopy-specific Grating Light Modulator (GLM) have been studied, which has importanr scientific significance and pratical value.On the basis of comparative analyze of some typical MOEMS light modulators, a novel Grating Light Modulator is presented with the advantages of simple structure, low drive voltage. More than that, it also can realize the modulation of Hadamard Transform. By establishing the elecromechanical model, the optical characteristics and electromechanical behavior of the GLM were studied. The parameters and structure were designed, and the simulation had been taken for finite element method analyzes by using professional software. The work of fabricate processes were also completed. The FPGA-based drive control system for GLM array was accomplished. According building the experimental platform, the device testing experiment was taken, and modulate functions were demonstrated.The main work of this thesis is as following:①Through comparative analyze, the operating principles of many kinds of MOEMS-based light modulators were summarizied. A novel Grating Light Modulator for micro spectroscopy was presented.②The principle of GLM was introduced. The optical characteristics was anlayized by adoping scalar diffraction theory.By building a mathematic model, electromechanical characters were studied.③On the basis of theoretical analysis, the structural parameters were defined. The design of Serpentine flexure and distributed electrodes were adopted The simulation had been taken for finite element method analyzes by Coventor Ware.④With considering actual fabrication technology of CETC No.24, the research of Polysilicon process was explored, and the problem of Al protect during sacrificial etching was also studied. Finally the GLM was fabricated by Al process.⑤The FPGA-based drive control system for GLM array was developed. According building the experimental platform, some relative parameters were verified, and the light modulation functions were demonstrated.