A substrate hot holes injection method is used to quantitatively examine the roles of electrons and holes separately in thin gate oxides breakdown.The shift of threshold voltage under different stress is discussed.It ...A substrate hot holes injection method is used to quantitatively examine the roles of electrons and holes separately in thin gate oxides breakdown.The shift of threshold voltage under different stress is discussed.It is indicated that positive charges are trapped in SiO 2 while hot electrons are necessary for SiO 2 breakdown.The anode holes injection model and the electron traps generation model is linked into a consistent model,describing the oxide wearout as an electron correlated holes trap creation process.The results show that the limiting factor in thin gate oxides breakdown depends on the balance between the amount of injected hot electrons and holes.The gate oxides breakdown is a two step process.The first step is hot electron's breaking Si-O bonds and producing some dangling bonds to be holes traps.Then the holes are trapped and a conducted path is produced in the oxides.The joint effect of hot electrons and holes makes the thin gate oxides breakdown complete.展开更多
The effect of substrate bias on the degradation during applying a negative bias temperature (NBT) stress is studied in this paper. With a smaller gate voltage stress applied, the degradation of negative bias tempera...The effect of substrate bias on the degradation during applying a negative bias temperature (NBT) stress is studied in this paper. With a smaller gate voltage stress applied, the degradation of negative bias temperature instability (NBTI) is enhanced, and there comes forth an inflexion point. The degradation pace turns larger when the substrate bias is higher than the inflexion point. The substrate hot holes can be injected into oxide and generate additional oxide traps, inducing an inflexion phenomenon. When a constant substrate bias stress is applied, as the gate voltage stress increases, an inflexion comes into being also. The higher gate voltage causes the electrons to tunnel into the substrate from the poly, thereby generating the electro,hole pairs by impact ionization. The holes generated by impact ionization and the holes from the substrate all can be accelerated to high energies by the substrate bias. More additional oxide traps can be produced, and correspondingly, the degradation is strengthened by the substrate bias. The results of the alternate stress experiment show that the interface traps generated by the hot holes cannot be annealed, which is different from those generated by common holes.展开更多
文摘A substrate hot holes injection method is used to quantitatively examine the roles of electrons and holes separately in thin gate oxides breakdown.The shift of threshold voltage under different stress is discussed.It is indicated that positive charges are trapped in SiO 2 while hot electrons are necessary for SiO 2 breakdown.The anode holes injection model and the electron traps generation model is linked into a consistent model,describing the oxide wearout as an electron correlated holes trap creation process.The results show that the limiting factor in thin gate oxides breakdown depends on the balance between the amount of injected hot electrons and holes.The gate oxides breakdown is a two step process.The first step is hot electron's breaking Si-O bonds and producing some dangling bonds to be holes traps.Then the holes are trapped and a conducted path is produced in the oxides.The joint effect of hot electrons and holes makes the thin gate oxides breakdown complete.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 60376024,60736033 and 60506020)the National High Technology Research and Development Program of China (Grant No 2003AA1Z1630)
文摘The effect of substrate bias on the degradation during applying a negative bias temperature (NBT) stress is studied in this paper. With a smaller gate voltage stress applied, the degradation of negative bias temperature instability (NBTI) is enhanced, and there comes forth an inflexion point. The degradation pace turns larger when the substrate bias is higher than the inflexion point. The substrate hot holes can be injected into oxide and generate additional oxide traps, inducing an inflexion phenomenon. When a constant substrate bias stress is applied, as the gate voltage stress increases, an inflexion comes into being also. The higher gate voltage causes the electrons to tunnel into the substrate from the poly, thereby generating the electro,hole pairs by impact ionization. The holes generated by impact ionization and the holes from the substrate all can be accelerated to high energies by the substrate bias. More additional oxide traps can be produced, and correspondingly, the degradation is strengthened by the substrate bias. The results of the alternate stress experiment show that the interface traps generated by the hot holes cannot be annealed, which is different from those generated by common holes.