DIFFERENTIAL TYPE FIELD-EFFECT TRANSISTOR OXYGEN SENSOR

摘要

PURPOSE:To enhance a temp. characteristic, by forming oxygen FET responding to oxygen and reference FET not responding to oxygen to the same substrate and performing the differential measurement of the output current or voltage of respective FETs. CONSTITUTION:Impurities are diffused in a silicon substrate 1 to form the source 2 and drain 3 of oxygen FET and the source 4 and drain 5 of reference FET. The silicon surface between the source and drain of each FET becomes a channel and an insulating film 6 is formed on said channel and a solid electrolyte film 7 is laminated to said film 6. The gate electrode 8 of the oxygen FET on the electrolyte film 7 is composed of a conductive body having the catalytic action of oxygen release reaction and the gate electrode 9 of the reference FET is constituted of a conductive body generating no oxygen release reaction. Then, by performing the differential measurement of the output current or voltage of each FET, a temp. characteristic can be enhanced.