▎ 摘　　要

NOVELTY - The biosensor has measurement sensor (S1) and a reference sensor (S2) are provided on the insulating substrate (10). Each of the probe molecules (16) is provided with first base moiety (14) that is provided on the measurement sensor. The one end of recognition moiety (15) is bound to the first base moiety and the other end is constituted to tip portion of the probe molecule. A second base moiety (24) is provided on the reference sensor. The first base moiety of each of the probe molecules is provided on the measurement sensor. The recognition moiety of each of the probe molecules provided on the measurement sensor is not present at a tip portion of the second base moiety. The first semiconductor layer includes graphene or carbon nanotubes. USE - Biosensor such as biosensor of FET type. ADVANTAGE - The identification accuracy of the target molecules is improved by using measurement sensors. The probe molecules are hardly detached and the reliability of the sensor is improved. The variations caused by noise are suppressed, and accuracy and reliability of measurement are enhanced. The influence on the crystal structure of the semiconductor layer is reduced, so that deterioration in characteristics is suppressed. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: a method for detecting substance to be detected by using biosensor; and an apparatus for detecting substance to be detected. DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of the biosensor. 10Insulating substrate 14,24Base moiety 15Recognition moiety 16Probe molecules S1Measurement sensor S2Reference sensor