that is the contact portion 13 corresponds to a position where the mass body 4 is stuck to the second sealing substrate 11 in embodiment 1 a concavity 14 is provided at a position where the second sealing substrate 11 faces the mass body 4 and the peripheral portion of the mass body 4 specifically at least a part of the peripheral portion thereof is configured to come into contact with the second sealing substrate 11 regarding the shape of the concavity 14 for example a belt like one illustrated in fig3 a rectangular one illustrated in fig4 and a circular one illustrated in fig5 can be presented fig3 through fig5 are explanatory views representing examples of the shapes of the concavity 14 which represent the cross section along the b b line in fig2 here the mass body 4 is indicated by alternate long and short dash lines in fig3 through fig5 while areas where the mass body 4 and the second sealing substrate 11 except for the concavity 14 overlap with each other corresponds to the contact portions 13 the capacitive acceleration sensor illustrated in fig1 and fig2 is produced using a semiconductor manufacturing technique after a silicon wafer on which at least forming portions of the mass body 4 and the beams 7 of the acceleration detecting portion the forming portion of the acceleration detecting portion in fig2 are formed by concave etching on the principal surface of the first sealing substrate 1 made of glass including silicon dioxide sio 2 or silicon so as to have a predetermined space for example a space of approximately.