Self-consistent electrical charging of insulating layers and metal-insulator-semiconductor structures

By means of a computer simulation the self-consistent charge transport with the current densities j(x,t), the respective charges rho (x,t), field strengths F(x,t), and potential distributions V(x,t) in SiO2 layers are obtained as a function of the insulator depth x and the injection time t. The SiO2 layers are considered as open layers on silicon substrate or they are embedded in metal-oxide-semiconductor (MOS) structures. The given currents of primary electrons, the field-dependent ballistic currents of secondary electrons and holes as well as the Fowler-Nordheim injection of electrons from the substrate into the dielectric layer are taken into account. This method allows a defined charge storage and the explanation of complicated emission, charging-up, and breakdown processes within insulating layers during electron bombardment and/or high-field charge injection from adjacent electrodes, e.g., in MOS structures. (C) 2001 American Institute of Physics.