Research And Application Of Electro-thermal Transmission Characteristics Of MEMS Micromirror

The electrothermal Microelectromechanical Systems(MEMS)micromirror generates a displacement or deflection based on the thermal expansion of the material by applying a voltage.MEMS micromirror is an important part of optical fiber communication,because it can process light of any wavelength and reduce the upgrade requirements of optical fiber lines,which provides the possibility of low cost and miniaturization of optical communications.Because the electrothermal MEMS micromirror utilizes the thermal expansion and contraction characteristics of the material,which also leads to the close relationship between the the temperature and deflection displacement,so it is very necessary to study the electrothermal transfer characteristics of the MEMS micromirror.In this paper,an electrothermal silicon beam MEMS micromirror was designed.Firstly,the mathematical and physical equations were used to discuss the electro-thermal transmission characteristics of the silicon beam structure.According to the silicon beam structure,a mathematical physical equation was established,and the temperature distribution of the silicon beam structure was solved according to the energy conservation principle.The effects of heat convection and radiation,input voltages,air layers thicknesses and structural parameters on the temperature distribution of the silicon beam structure were discussed.Then,the finite difference method was used to discuss the electro-thermal transfer characteristics of the silicon beam structure.A finite difference equation was established based on the silicon beam structure,and the temperature distribution of the silicon beam structure was solved according to the difference principle.The effects of input voltages,air layers thicknesses and structural parameters on the temperature distribution of the silicon beam structure were discussed.The model of electrothermal silicon beam MEMS micromirror was established using COMSOL simulation software,and the temperature distributions under different input voltages,air layers thickness and structural parameters were solved respectively.The temperature distributions solved by mathematical physics equations and finite difference methods were compared with COMSOL simulation software.Finally,the temperature of the electrothermal MEMS micromirror silicon beam structure was measured using an infrared thermal imager.The temperature errors calculated using the mathematical physics equation and the finite difference method are 0.044% and 1.46%,respectively.Since the error is negligibly small,the electro-thermal transmission characteristics of the electrothermal silicon beam MEMS micromirror can be analyzed using the model established by the mathematical physics equation and the finite difference method.