Hole Energy Dependent Interface Trap Generation in MOSFET Si/SiO{sub}2 Interface

摘要

The nature and composition of generated interface-trap (ΔN{sub}(IT)) in p-MOSFETs is studied as a function of hole energy. By observing the time dependence of generation during stress and the amount pf recovery after stress, it is shown that ΔN{sub}(IT) is due to both broken ≡Si-H and ≡Si-O- bonds, their ratio governed by hole energy. In the absence of hot holes ΔN{sub}(IT) is primarily composed of broken ≡Si-H, which show a lower power-law time exponent and a fraction of which anneal after stress. Additional ΔN{sub}(IT) is created in the presence of hot holes, which is due to broken ≡Si-O- bonds. These traps show a much larger power-law time exponent, and they do not anneal after stress. These observations have important implications for lifetime prediction under negative bias temperature instability, Fowler-Nordheim, and hot carrier injection stress conditions.