| 摘要 |
PURPOSE:To provide a highly reliable semiconductor ion sensor by constituting an ion sensitive layer of a silicon nitride film having a stable composition against water, etc. CONSTITUTION:In the ISFET 5 of the title ion sensor 1 having a source diffusion area 51, drain diffusion area 52, gate oxide film 54, and ion sensitive film 55, the ion sensitive film 55 in its gate section 5a is constituted of a hydrogen- free silicon nitride film formed by the DC magnetron sputtering method in a low-temperature atmosphere of about 200 deg.C in an N2/Ar-mixed gas. The ratio of the flow rate of the N2 gas to that of the mixed gas is set at >=0.6. |
