Patent ID: 7261825

Claim:
A method for producing a micromechanical oscillating mirror device, comprising: providing one of an SOI and an EOI structure having a silicon substrate layer, an oxide layer provided on the silicon substrate layer, and an Si functional layer provided on the oxide layer, wherein an upper region of the silicon substrate layer is provided as a sacrificial layer; forming at least a first trench that extends through the functional layer to the oxide layer, by a first anisotropic plasma etching step that exposes a laterally-formed island region in the functional layer; providing a passivating layer that covers at least the sidewalls of the trench; extending a bottom of the first trench to the silicon substrate layer by a physically directed etching; deep etching the first trench using a second anisotropic plasma etching step starting from the bottom of the trench and extending the trench to a predetermined depth of the silicon substrate layer, wherein the second anisotropic plasma etching step specifies the depth of the sacrificial layer; and performing an isotropic sacrificial layer etching step starting from the first trench to remove a region of the sacrificial layer below the island region by lateral etching undercutting of the silicon substrate layer, whereby the island region is exposed and made vertically movable.