Characteristics of LIGA PMMA micromirror for MOEM optical switch application

We investigated characteristic of LIGA PMMA (polymethylmethacrylate) micromirror for MOEM optical switch application. The optical switching device was designed and fabricated in multi-layered polysilicon using the LPCVD process. We performed adhesion test on silicon and silicon oxide and acid test by anhydrous HF GPE (gas-phase etching) and 6:1 BHF wet etch processes for thin and thick gold-coated PMMA micromirrors. Normalized reflectance and surface roughness are measured by UV Spectrometer and WYKO interferometer, respectively. We found that the reflectance of gold-coated PMMA micromirror on the silicon surface was above 90%.