Breakdown characteristics of gate and tunnel oxides versus field and temperature

The wearout and breakdown parameters of representative gate and tunnel oxides are evaluated versus temperature, electric field and polarity. A frontier close to 127°C between two regions with different activation energies is clearly demonstrated. However, the negative charge build‐up under high field stress is correlated with the breakdown. The field acceleration factor is found to be constant in the range 8·5–12·5 MV/cm. The time‐to‐breakdown distributions can be described both by the E and the 1/ E models. Finally, the thickness dependence of the field acceleration factor is quantified for oxide layers with a thickness in the range between 10 nm and 50 nm.