PURPOSE: To obtain a small-sized semiconductor acceleration sensor of high function, by a method wherein a part serving as a lever is wrapped with an etching resistant thin film, and the lever is formed by working from a single surface.

CONSTITUTION: Photoresist is spread on the upper surface of an SiNx film 7, and eliminated to obtain the form of a lever pattern 14. An SiO2 film 6 and the SiN, film 7 are eliminated in the form of the lever pattern 14 bu applying the photoresist to a mask. The photoresist on a wafer is eliminated. In this case, the lever pattern 14 is made larger than a lever pattern 13 which has been first used, and the lever part containing the part where the pattern of a weight is formed is wrapped with the SiO2 film 6 and an SiO2 intermediate layer. Since the lever part containing the part where the pattern of the weight is formed is wrapped with the SiO2 film 6 and the SiO2 intermediate layer, said part is not etched. Thus a lever and a substrate Si layer 1 are unified in a body, in the root part of the lever.