In this study the temporal characteristics of the current through thin silicon oxide films have been analyzed applying pulsed voltages of different height to the device under test. In addition to low and high field stress measurements, we also have included pre-tunneling voltages to compare several voltage stress tests. We have shown for the first time, that there is a steady transition in the variation of the current characteristic going from pre-tunneling voltages to high voltage stressing. This current characteristic has been explained by the superposition of two current components. The measurement results have been discussed with the aid of a model based on the energy band diagram. Furthermore, we will show that the temporal transient current component can also be seen in the Fowler-Nordheim tunneling plot.