This paper investigates the laminated photoresist sacrificial layer technology and residual stress in micromirror fabrication. Different problems in electroplating related to the photoresist sacrificial such as pollution are discussed and their solutions are proposed．Through experiments

it was found that the solvent of the upper photoresist penetrates the electroplating base metal layers and dissolves the sacrificial layer behind it; a new fabrication process is developed. The residual stresses in thin metal films can affect the device properties. And the investigation of the residual stress origin and how to control are shown. Some valuable experimental parameters were obtained. Employing the new technologies

we fabricate perfect flat micromirror with the size of 620×500×2 μm3

air gap’s height of 12μm.