A method for testing the reliability of a dielectric film on semiconductor substrate

摘要

The method comprises the steps of: establishing a current value corresponding to a first set time increment in which current is first applied for testing the reliability of the film; applying the established current to the film; applying a current in each succeeding time increment 0, 2, .... 16 and measuring the charge applied until the film breaks down. The current in each succeeding time increment is increased. The current value in each time increment is itself divided by a predetermined denominator value and the divided value applied incrementally to the film (Fig. 3 not shown). The determination of breakdown is made at a predetermined delay after the application of the divided value increment (Fig.3). The method enables reliability dependent on breakdown of the film as well as degradation in performance due to hot carrier injection to be investigated. Coarse measurement can be made by dividing the increments by a low number eg 3. More discrimination can be obtained by dividing by larger numbers eg 25. IMAGE