Mass sensor and mass detection method

Abstract

A mass sensor (30) in which a connection plate (33) and a diaphragm (31) are joined together at their respective sides; a sensing plate (32) is joined to the connection plate (33) at their respective sides in the direction perpendicular to the direction where the diaphragm (31) is joined to the connection plate (33); a piezoelectric element (35) consisting of a piezoelectric film and an electrode is installed on at least either one of plate surfaces of the sensing plate (32); and a resonating portion consisting of the diaphragm (31), the sensing plate (32), the connection plate (33), and the piezoelectric element (35) is joined to a sensor substrate (34). Change in the mass of the diaphragm (31) is measured by measuring change in the resonant frequency of the resonating portion accompanying the change in the mass of the diaphragm (31). The mass sensor of the present invention enables the easy and accurate measurement of a minute mass of a nanogram order including microorganisms such as bacteria and viruses, chemical substances, and the thickness of vapor-deposited films.

Dependencies are inferred from the claim text.