To enhance the manufacturing efficiency by enabling a sensor to be miniaturized and to be made thinner.

When the sensor has a sensor chip 12 where a strain gage element is placed on a diaphragm 121 to detect the physical quantity of the diaphragm 121 and convert the same into an electric signal, a flexible board 13 is provided via a bump 21 on the upper surface of the diaphragm 12, on which the strain gage element is placed, and an electric circuit 23 amplifying the electric signal for output is provided on the flexible board 13. Since the electric circuit 23 on the flexible board 13 and the strain gage element on the diaphragm 121 are electrically connected together by the bump 21, a thinner thickness is achieved and a connection can be made through die bonding, so that the manufacturing time of the sensor can be reduced greatly.