The structure formation method uses a layered plate (100) having a dielectric layer (3) between (2) silicon layers (1,2), the dielectric layer having (2) silicon oxide layers (4,6) and an intermediate silicon nitride layer (5). Several troughs (12) are etched in one silicon layer (1), which has a thickness of up to (5) times less than the other silicon layer (2) before etching a recess (10) in the latter using an etching solution.
