Patent ID: 7863072

Claim:
A method for producing a micromechanical diaphragm sensor having at least one first diaphragm, a second diaphragm essentially disposed above the first diaphragm, a first cavity, and a second cavity essentially disposed above the first cavity, the method comprising: producing a first protective layer on a substrate; producing at least one opening in the first layer, down to the substrate; depositing a first diaphragm layer on the first protective layer; patterning the first diaphragm layer; producing a second protective layer on at least a portion of the first diaphragm layer; producing at least one opening in the second protective layer, down to the first diaphragm layer; depositing a sacrificial layer on the second protective layer; producing a third protective layer on at least a portion of the sacrificial layer; depositing a second diaphragm layer; producing at least one opening in the second diaphragm layer and in the third protective layer, down to the sacrificial layer; wherein the two cavities are produced in one etching step by dissolving out a portion of the sacrificial layer, the first diaphragm layer, and the substrate.