Dependence of interface-state generation on field polarity in metal-oxide-silicon devices of various thicknesses and technologies

High electric-field stresses were performed in polycrystalline silicon gate metal-oxide-semiconductor devices (capacitors and transistors) and defect generation was studied as a function of injecting electron densities for po larities of different high electric fields. This work was performed for dif ferent oxide thicknesses and technologies. The results show that the interf ace states were generated during electron injections from the silicon-subst rate saturate. However, they present no saturation when created during elec tron injections from the gate. Our results show that the amount of this asy mmetry depends strongly on oxide thickness, but it is oxide technology inde pendent. A detailed analysis of our results allows us to suggest that a dir ect creation mechanism occurs when the injecting electrode is the gate. Ano de-hole injection and trap-creation mechanisms are present under the two st ress oxide field polarities, but their effects are reduced with decreasing oxide thickness.