| 摘要 |
PURPOSE:To obtain a sensor simple in the application with limited dimensions, by bringing an electrolytic aqueous solution, with the hydrogen ion density varying in accordance with changes in the concentration of CO2, into contact with a gate region of an ion sensitive FET. CONSTITUTION:After a part of an Si substrate 1 with a recess 3 formed is converted into a p<+> type, an SiO2 film 5 is formed as gate insulation film. Then, a part of the SiO2 film 5 is removed and ions are injected to form a source and drain 11 and a source-drain contact area 15. Subsequently, after the formation of an SiO2 film 6 and an Si nitride film 7, an electrode 16 is formed. Then, a silver/silver chloride reference electrode 50 insulated from the source and drain is formed near a source electrode on the films 6 and 7 to obtain an ion sensitive FET. An agallose gel 8 containing an electrolytic aqueous solution fill the recess 3 to form a stationary film 9 and a gas permeable film 10. |
