A method for manufacturing a micromechanical device layer is performed on a device wafer comprising a single layer of homogenous material. The method comprises patterning a first mask on a first face of the device wafer, the first mask patterning at least lateral dimensions of comb structures and outlines of large device structures. First trenches are etched, the first trenches defining the lateral dimensions of the at least comb structures and outlines of large device structures in a single deep etching process. Recession etching may be used on one or two faces of the device wafer for creating structures at least partially recessed below the respective surfaces of the device wafer. A double mask etching process may be used on one or two faces of the device wafer for creating structures at least partially recessed to mutually varying depths from the respective face of the device wafer.