摘要 |
The present invention discloses a method for obtaining a distribution of charges along a channel of a MOS transistor, which is used for obtaining distributions of interface states charges and charges of a gate dielectric layer in the MOS transistor. The method includes: adding a MOS transistor into a test circuit; measuring two charge pumping current curves when a source terminal is open-circuited or when a drain terminal is open-circuited before and after a stress is applied by using a charge pumping current test method, where one of the two charge pumping current curves is an original curve and the other one is an post-stress curve; finding a point B corresponding to a point A on the original curve on the post-stress curve, and estimating amount of locally-generated interface states charges and charges of the gate dielectric layer by a variation of the charge pumping current and a variation in a voltage at a local point. As compared with a conventional method for obtaining a distribution, the method of the present invention can obtain a distribution of charges along a direction form the drain or source terminal to the channel more easily and rapidly, with an aid of a computer. A mass of complicated and repeated tests are reduced. Also, the method can provide an effective base for improving device reliability.
|