Relaxation of positive charge during bidirectional electric stress on metal-oxide-silicon capacitors

Relaxation phenomena of positive charges, created in a metal-oxide-silicon capacitor by bidirectional Fowler-Nordheim electron injections under consta nt current, have been studied and their kinetics have been quantitatively c haracterized. After creation, positive charges are neutralized under electr on injections at constant current. The gate bias shift caused by the neutra lization process has an exponential dependence on time during relaxation ir respective of stress field polarity and stress duration. Analysis of data a ssuming nonelectron detrapping gives capture cross section values in the ra nge of 3.5-6.7 x 10(-16) to 2.1 x 10(-15) cm(2). The compilation of data gi ven in literature and our present results shows that the main responsible d efect in the oxide is the amphoteric traps negatively charged near the cath ode and positively charged near the anode. (C) 1999 American Institute of P hysics. [S0021-8979(99)03523-9].