Tunneling induced charge generation in SiO2 thin films

Charge buildup in thermally grown SiO2 thin films due to Fowler-Nordheim tunneling has been investigated, Both positive and negative oxide charge can be generated by the tunneling current. The stress fluence, voltage amplitude, and polarity dependence of the positive charge generation points to impact ionization occurring near the oxide substrate interface as the most likely source of this charge. The centroid location and density of the negative oxide charge are used to analyze the negative charge generation process at different stress voltage levels and temperature. A theoretical model is proposed and compared with the experimental data. (C) 1998 American Institute of Physics. [S0021-8979(98)06507-4].