METHOD FOR PRODUCING A MICROMECHANICAL MEMBRANE STRUCTURE HAVING FIXED COUNTER ELEMENT

摘要

The present invention proposes a method for producing a micromechanical membrane structure (11) having a fixed counter element (12), which starts from a p-doped silicon substrate (1). Said method comprises the following processing steps: n-doping of at least one coherent latticed area (2) of the substrate surface; (Figure 1a) porous etching of a substrate area (3) below the n-doped lattice structure (2); (Figures 1b-c) oxidation of the porous silicon; (Figure 1d) generating at least one sacrificial layer (5) above the n-doped lattice structure (2); (Figure 1e) depositing and structuring at least one thick epitaxial layer (7); (Figures 1f-g) removing the sacrificial layer (5) between the thick epitaxial layer (7) and the n-doped lattice structure (2) and generating a cavity (10) in the silicon substrate (1) below the n-doped lattice structure (2) by removing the oxidized porous silicon (oxPorSi); (Figure 1h) so that the exposed n-doped lattice structure (2) forms a membrane structure (11) and at least one fixed counter element (12) is implemented in the structured thick epitaxial layer (7).