Packaging and testing of electro-magnetically actuated silicon micro mirror for Pico-projector applications

Micro mirror packaging development for pico-projector application requires integration of magnets, silicon spacer and glass cap. A multilayer stack package has been designed for large deflection micro mirror. The magnets are used for electromagnetic actuation and are attached on either sides of the silicon beam by a pick and place machine. Different epoxy materials are evaluated to optimize the magnet attachment to the silicon beam. A silicon spacer with a thickness of 500um is epoxy bonded to the micro mirror chip so that after capping the mirror can deflect freely. A glass substrate with antireflection coating is used as a cap for transmitting the light into the mirror. Optical transmission testing at a wavelength of 639nm found that 99%of light can be transmitted through the AR coated glass substrate. The fully package micro mirror device is tested for mirror deflection and found that no performance degradation due to packaging.