Restoring OFF-state stress degradation of threshold voltage

摘要

A method for at least partially compensating for a change in threshold voltage level of a FET transistor induced by OFF-state stress degradation includes determining a signal indicative of a change in threshold voltage level of the FET with respect to a reference threshold voltage level, and applying a restoration signal to the FET. This restoration signal is adapted for shifting the threshold voltage level of the FET in a direction having opposite sign with respect to the change in threshold voltage level. Applying the restoration signal further includes taking into account the signal indicative of the change in threshold voltage level.

主权项

1. A method for at least partially compensating for a change in threshold voltage level of a field-effect transistor induced by OFF-state stress degradation, the method comprising:
determining a signal indicative of a change in threshold voltage level of the field-effect transistor with respect to a reference threshold voltage level; and applying a restoration signal to the field-effect transistor, wherein applying the restoration signal comprises applying at least one voltage pulse to the field-effect transistor such that a gate terminal of the field-effect transistor is connected to a higher voltage level than a drain terminal of the field-effect transistor and to a higher voltage level than a source terminal of the field-effect transistor, wherein the restoration signal is adapted for shifting the threshold voltage level of the field-effect transistor in a direction having an opposite sign with respect to the change in threshold voltage level, and wherein applying the restoration signal includes taking into account the signal indicative of the change in threshold voltage level.