Trap generation and electron detrapping in SiO2 during high‐field stressing of metal‐oxide‐semiconductor structures

Direct evidence for electron trap generation during high‐field stressing of thermally grown SiO2 layers is obtained using avalanche injection followed by internal photoemission measurements on Al‐gate metal‐oxide‐semiconductor structures. Avalanche injection is used to fill oxide traps with a minimum risk of oxide degradation. It is shown that traps are created near the Si‐SiO2 interface of a 39‐nm‐thick oxide on p‐Si stressed in accumulation. After intentional charging the centroid of the additional charge distribution corresponding to the newly created traps is located at 5(±2.5) nm from the Si‐SiO2 interface. Any bulk oxide charge is detrapped during a high‐field stress. The importance of these findings in relation to breakdown in SiO2 is indicated.