PURPOSE: To obtain an apparatus obstructing the influence of the distortion stress of the header side with a simple method, by sticking and fitting a silicon pedestal of a pressure sensor chip to a minutely projected part formed in a body on the header surface of a package.

CONSTITUTION: A minutely projected part 31a having e.g. about 1W2.5mm2 area and 0.2W0.5mm height, is formed in a body at the central part of a header 31 of a package. Further, a pressure sensor chip 10 is stuck and fitted to said part 31a by e.g. an Au-Si eutectic solder 32. In this manner, the influence of the distortion stress produced at the side of the header 31 exerting on the side of the chip 10 is obstructed sufficiently and orignal characteristic of the chip 10 itself are put to practical use sufficiently, and the accurate measurement of the external pressure is performed.