Hydrogen ion sensitive semiconductor sensor

Abstract

Abstract PURPOSE:To achieve a higher water resistance and a higher sensitivity, by arranging a water resistant film and a hydrogen ion sensitive silicon nitride film expressed by SiNx (x<1.2 or x>1.5) sequentially on a gate electrode insulation film of an FET. CONSTITUTION:An n-type source region 2 and a drain region 3 are formed on a p-type Si single crystal 1 by doping and a gate electrode insulation film 5 made of SiO2 is formed thereon. Then, a water resistant film 6 as first silicon nitride film SiNx (1.2<x<1.5) and a hydrogen ion sensitive film 7 as second silicon nitride film SiNx (x<1.2 or x>1.5) are formed on the insulation film 5. With a gate voltage made constant, an FET thus obtained is immersed into a solution and the density of hydrogen ions is detected from the drain current, thereby achieving a higher water resistance and a higher sensitivity.

Inventors

• 👤 Akihiko Mochizuki
• 👤 Hideyo Iida

Bibliographic Details