| 摘要 |
PURPOSE:To concentrate sensor parts at the point of a substrate and to improve the yield of products by a method wherein insulation between the sensor part and an electrolyte is performed by means of a semiconductor insulating film and a polysilicon doped with impurity is laminated fon an intermediate wiring part. CONSTITUTION:On a semiconductor substrate 1, a common drain area 5 and plural source areas 2-1, 2-2 are formed. Wiring is performed between source electrodes S-1 and S-2 corresponding to the source areas 2-1, 2-2 by means of a polysilicon 7-2 containing impurity by using an SiO2 film. And further, using an oxide film, wirings are performed between other areas and the corresponding source electrodes by sequentially laminating a polysilicon 7-1, thus, the compound field effect transistor for ion sensor being constituted. With this, an inner wiring is performed optionally and insulation for blood, etc. is easily performed. And further, a size can be made small and a diffusion process can be reduced. |
