Patent ID: 11969757
Assignee: STMICROELECTRONICS S.R.L.
Field: Chemical engineering (Chemistry)
Classification: CPC B  H | IPC B  H

Claim 9:
10. A device, comprising:
one or more external lateral walls;
a monocrystalline silicon substrate including a first surface and a second surface opposite to the first surface, one or more internal lateral walls that are spaced inward from the one or more external lateral walls and that extend into the second surface of the monocrystalline silicon substrate;
a monocrystalline silicon membrane element coupled to the monocrystalline silicon substrate, the monocrystalline silicon membrane element including a third surface and a fourth surface opposite to the third surface;
at least one monocrystalline anchor portion that couples the monocrystalline silicon membrane element to the monocrystalline silicon substrate, the at least one monocrystalline anchor portion directly coupled to and formed on the first surface of the monocrystalline silicon membrane element, the at least one monocrystalline anchor portion is made of a continuous material along with the monocrystalline silicon membrane element, and the at least one monocrystalline anchor portion includes one or more notch sidewalls, the one or more notch sidewalls being directly on the second surface;
a vent hole extending through the monocrystalline silicon membrane element from the third surface to the fourth surface; and
a cavity extending into the first surface of the monocrystalline silicon substrate to the third surface of the monocrystalline silicon membrane element, the cavity including:
a first portion delimited by the one or more internal lateral walls of the monocrystalline silicon substrate; and
a second portion wider than the first portion, the second portion includes one or more notches spaced outward from the one or more internal lateral walls of the monocrystalline silicon substrate and delimited by the one or more notch sidewalls, and the second portion is delimited by the one or more notch sidewalls, the second surface, and the third surface, and

wherein the first surface is devoid of any other material other than the at least one monocrystalline anchor portion.