It is an object of the present invention to provide a technique that can realize improvement of sensitivity of a vibrator. A platform 50 to which a substance adheres or sticks is provided to be mechanically coupled to a vibrator 20 of a sensor via bridges 51. Sensitivity of the sensor is improved by causing the mass of a substance adhering or sticking onto the platform 50 as if the substance concentratedly adheres or sticks to places where the platform 50 is connected to the vibrator 20. It is preferable to connect, via the bridges 51, the platform 50 to places where the platform 50 vibrates integrally with the vibrator 20. For this purpose, it is preferable to mechanically couple, via the bridges 51, the platform 50 to regions where vibration occurs only in one of an r direction or a θ direction in the vibrator 20.