Abstract
Investigating the behaviour of ISFETs with a Ta2O5SiO2 dielectric it has been observed that their long-term stability is strongly influenced by previous exposures to daylight. A Ta2O5 layer, as prepared for ISFET application, will become conductive by exposure to optical radiation. This conduction is due to bulk traps with a depth of 1.6–3.2 eV. It is shown that a low temperature anneal step in the presence of an A1 layer on top of the Ta2O5 layer may eliminate these traps and reduce the associated threshold voltage instability.
Original language | English |
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Pages (from-to) | 350-353 |
Number of pages | 4 |
Journal | Sensors and Actuators B: Chemical |
Volume | 1 |
Issue number | 1-6 |
DOIs | |
Publication status | Published - 1990 |