INTERFACE STATE GENERATION IN P-TYPE SI METAL/OXIDE/SEMICONDUCTOR CAPACITORS DUE TO FOWLER-NORDHEIM TUNNELING CURRENT STRESS

The interface state generation in (100) p-type Si metal/oxide/semiconductor capacitors due to Fowler-Nordheim tunneling current stress has been studied by means of multifrequency ac conductance measurements at room temperature. The results show that two kinds of interface states in the upper and lower halves of the gap are generated at different introduction rates. It is found that the capture cross sections of the two interface states change in an opposite way with increasing interface state density. The degradation mechanism of Si MOS capacitors is discussed in relation to the defect creation and the peculiar behavior of the capture cross section. In particular the capture cross section of the interface states in the upper half of the gap decreases rapidly as the density of the interface states is increased.