PURPOSE: To provide an oxygen sensor where oxygen is firmly fixed to a solid carrier and an output voltage can be obtained for a long time stably and its manufacturing method.
CONSTITUTION: ISFET (ion selectivity FET) is treated by silane coupling agent and then is heated at 110°C for 20 minutes, thus forming a covalent bonding between aminopropyltriethoxylane and the surface a gate insulation film 30. Then, ISFET is dipped into bicarbonate buffer liquid with pH8.0 containing biotinlongarm 36 with 0.1 mg/ml concentration, thus forming a covalent bonding between the biotinlongarm 36 and aminopropyltriethoxylane. Then, ISFET is dipped in 100ml phosphorous acid buffer liquid with pH7.2 containing 1mg urease 40 which avidin D38 is combined to for two hours. In the meantime, biotin 34 and avidin 38 are subjected to specifical bonding reaction.
UMIBE KATSUAKI
KATO MASAKAZU
MIYAMOTO HIROO
