Patent ID: 7381656

Claim:
A method of manufacturing a semiconductor device comprising a substrate and a semiconductor body in which at least one semiconductor element is formed, wherein, in the semiconductor body, a semiconductor island is formed by forming, in the surface of the semiconductor body, a first recess the walls of which are covered with a dielectric layer ( 6 ), after which a lateral part of the semiconductor body is removed by means of underetching via the bottom of the first recess, thereby forming a cavity in the semiconductor body above which the semiconductor island is formed, and wherein a second recess is formed in the surface of the semiconductor body, the walls of said second recess being covered with the dielectric layer, and one of the walls of the second recess covered with the dielectric layer being used to form a side wall of the semiconductor island, characterized in that a lateral dimension of the second recess and the thickness of the dielectric layer being chosen such that the second recess is filled substantially completely by the dielectric layer, and the lateral dimensions of the first recess being chosen such that the walls and the bottom of the first recess are provided with a uniform coating by the dielectric layer.