pH ISFET Sensors
ISFET (Ion Sensitive Field Effect Transistors) are non-glass pH electrodes. Their fabrication with microelectronic technologies offers advantages like robustness, small size and low cost compared to standard pH glass electrodes.
IMB-CNM fabricates several designs of ISFETs. These contain SiO2 gate membranes for measuring pH.
SiO2 ISFET Chip
Detail of a encapsulated ISFET sensor
- Standard NMOS based technologies.
- Fully CMOS compatible technology with on chip circuit integration.
- Biocompatible and Organic membranes for ion selective detection.
- Automatic packaging based on thermocurable and photocurable encapsulant polymers.
- Small size, adaptable to miniaturized systems.
- Robustness due to non-glass and solid state nature.
- Response time up to 10 times faster than glass electrode.
- High long-term stability.
- High reproducibility.
- Low impedance output signal.
- Low cost (mass production).
- Stores dry, no maintenance required.
- Biomedical analysis.
- Environmental monitoring.
- Industrial process control