The image force effects and quantized level effects in MOS structures under high electric field stressing will cause the variations of emitting potential barrier and Fowler-Nordheim tunneling current. In this paper

this kind of potential barrier modulation and its effects on tunneling of electrons and measurement of traps in MOS structures at high electric field have been studied. Furthermore

some corrected methods with the potential barrier modulation considered are also presented in order to get more accurate results.