| 摘要 |
A semiconductor gas sensor has a CMOS inverter formed from an n-channel field-effect transistor provided with a catalytic gate and a p-channel field-effect transistor provided with a catalytic gate. The input setting gate potential (Vin (D)) of the CMOS inverter is set using the threshold sensor response strength (∆Vgth) determined by the concentration of the gas to be detected and the threshold input potential of the CMOS inverter (Vtc) so that Vin (D) = Vtc − ∆Vgth. As a result, it is possible to produce an alarm or warning for the gas concentration to be detected simply by setting the input setting gate potential (Vin (D)). Further, a characteristic coefficient (&bgr;R), n-channel field-effect transistor threshold voltage (Vtn), and p-channel field-effect transistor threshold voltage (Vtp) are set so that &bgr;R = 1 and Vtp = −Vtn, thereby reducing temperature correction resulting from threshold voltages caused by the MOS structure and not by the gas to be detected. |
