Stress-induced leakage current reduction by a low field of opposite polarity to the stress field

Stress-induced leakage currents in 7 and 12 nm thick gate oxides of metal-oxide-semiconductor capacitors, created by negative or positive high field stress, were investigated in details, it is known that stress-induced leakage currents have several components. One of these components, which is observed for both stress and measurement polarities, increases drastically when the oxide thickness decreases. We have observed that this component magnitude is reduced when a low field of opposite polarity to the stress field is applied to the oxide after stress. This effect does not seem to be due to electron trapping in the oxide bulk, during the low held application. We propose therefore, that this current decrease is due to a defect relaxation phenomena induced by the low field. This proposition is compatible with any defect creation process which involves a stress-field-induced motion of atoms. (C) 1998 American Institute of Physics. [S0021-8979(98)03020-5].