Effect of an Al overlayer on interface states in poly-Si gate MOS capacitors

The presence of an aluminum overlayer on the polysilicon gate of MOS capacitors was found to enhance the generation of interface states strongly by ionizing radiation and Fowler-Nordheim electron injection. The effect is eliminated by removal of the metal before, but not after, sintering. The reduction, during the sinter, of water-related species by the aluminum, producing atomic hydrogen, is suggested as the probable cause of this behavior.<<ETX>>